Key points
About this chapterThis chapter is based on the following WHO guidelines: Monitoring national cervical cancer prevention and control programmes: quality control and quality assurance for visual inspection with acetic acid (VIA)-based programmes. Geneva: WHO; 2013. (http://www.who.int/reproductivehealth/publications/cancers/9789241505260/en/). WHO guidelines for screening and treatment of precancerous lesions for cervical cancer prevention. Geneva: WHO; 2013. (http://www.who.int/reproductivehealth/publications/cancers/screening_and_treatment_of_precancerous_lesions/en/) [PubMed: 24716265]. WHO guidelines for treatment of cervical intraepithelial neoplasia 2–3 and adenocarcinoma in situ. Geneva: WHO; 2014. (http://www.who.int/reproductivehealth/publications/cancers/treatment_CIN_2-3/en/). WHO guidelines: use of cryotherapy for cervical intraepithelial neoplasia. Geneva: WHO; 2011. (http://www.who.int/reproductivehealth/publications/cancers/9789241502856/en/) [PubMed: 23741775]. WHO technical specifications on cryosurgical equipment for the treatment of precancerous cervical lesions and prevention of cervical cancer: WHO. 2012. (http://www.who.int/reproductivehealth/publications/cancers/9789241504560/en/). This chapter provides detailed information on screening and treatment for cervical pre-cancer. It includes seven main sections, beginning with a description of the considerations relating to health-care providers (section 5.1), followed by an overview of issues relating to cervical cancer screening, including risks and benefits and ethical considerations (section 5.2). Section 5.3 describes the available screening tests (molecular HPV testing, visual screening methods and cytology-based screening) and their comparative strengths and limitations. Section 5.4 reviews diagnostic modalities (colposcopy, biopsy and endocervical curettage) used to confirm and map abnormalities in some women with positive results on screening. In section 5.5, treatment procedures for detected pre-cancer (cryotherapy, LEEP and cold knife conization) are described in some detail, including indications, strengths and limitations of each procedure. Section 5.6 covers possible complications and follow-up after treatment. Finally, section 5.7 of this chapter emphasizes that to have an impact on the incidence and mortality associated with cervical cancer, it is essential to link screening to further management for all women who receive a positive screening result. Programmatic strategies that can be used to successfully accomplish this crucial link are the “screen, diagnose and treat” approach, or the “screen-and-treat” approach – both are discussed. Recommendations presented in this chapter for the screening and diagnostic tests and treatments to use in a cervical cancer prevention and control programme meet WHO evidence-based criteria and provide guidance to programme managers and health-care providers. The practice sheets pertaining to this chapter contain need-to-know information for the service provider on the steps for obtaining informed consent, performing a pelvic examination, and for conducting each screening test and treatment modality discussed. Practice Sheet 5.7 includes guidance on counselling patients after positive screening results. Maria's storyMaria is a 40-year-old Nicaraguan woman who, with her husband and three children, lives in a rural community. The community health worker came to visit and informed her that she is of an age when a woman should be tested to see if there have been any changes on her cervix that could get worse if not treated, and which could eventually, many years later, turn into cancer. She was then invited to attend a clinic in a nearby community where a team of nurses from the local hospital would be coming to provide all women aged 30–49 years with a test for pre-cancer of the cervix. She would be given the result of the test before returning home and all women needing treatment can also have it the same day before going home. Several days before the clinic, a nurse came to Maria's community and gathered all the women to give them information about the test that would be used and details about the treatment, including the fact that neither the test nor the treatment cause much pain but may be uncomfortable. On the day of the clinic, Maria and 10 other women from her community walked together to the clinic with the community health worker; there they sat with an auxiliary nurse in a private spot where each woman had her health history taken and was able to receive answers to all her questions. The test was performed in a private room and after Maria was dressed, she was told that her cervix was normal and that she just needed to have the test repeated in five years' time. Of the 10 women who came with her, two were told their cervix had a slight abnormality that needed treatment so that it wouldn't get worse. One decided to be treated the same afternoon and the other decided she wanted to come back with her partner to the follow-up clinic a week later in the same place. Both women who needed treatment were quite glad they had gone to the clinic and felt very pleased with their experience; they then recommended to their female relatives and friends between the ages of 30 and 49 years to follow the same path and get screening – and treatment, if needed – so they, too, could stay free from cervical cancer. 5.1. Health-care providers5.1.1. The role of health-care providersThe health-care provider is a central figure in any coordinated public health effort to prevent and control cervical cancer. The role of the health-care provider at all levels is to ensure that women are educated about cervical cancer, that quality services are offered, and that women who need it receive the appropriate follow-up care and treatment for positive screening results or for invasive cervical cancer. Health-care providers work in coordination with each other and with the ministry of health, programme planners, managers and community workers to ensure an effective programme. 5.1.2. Who can provide good quality screening?With competency-based training, any provider who knows how to do a speculum examination can perform any of the cervical cancer screening tests (i.e. nurse, auxiliary or assistant nurse, trained midwife, clinical officer or medical doctor). For more information on training community health workers, see Practice Sheet 3.7. 5.1.3. Client assessment and preparation for screeningWomen should have a basic assessment before proceeding to the screening test; it should include information and counselling, a brief social and clinical history, and a simple pelvic examination. The following points provide further details relating to the role of health-care providers at this stage:
5.1.4. Other health problems detected during screeningThe woman and her health needs must be the focus of prevention programmes. When possible, providers should adopt a comprehensive approach to identification and management of sexual and reproductive health problems. The provider should pay particular attention to signs and symptoms suggestive of cancer, sexually transmitted infections (STIs) or other conditions detected during history-taking and pelvic examination. Women with abnormal findings unrelated to cervical cancer screening can be treated or referred, as appropriate. In addition, women should be offered an opportunity to raise personal concerns regarding sexual and reproductive health issues, such as any unmet need for family planning. 5.2. Cervical cancer screening5.2.1. What is screening?Screening is a public health intervention provided to an asymptomatic target population. Screening is not undertaken to diagnose a disease, but to identify individuals with increased probability of having either the disease itself or a precursor of the disease. Not all diseases are appropriate for a screening programme. The following criteria help determine whether a disease is appropriate for a screening programme:
The natural history, screening tests and treatment options for cervical pre-cancer meet these criteria. 5.2.2. Cervical cancer screening: an overviewCervical cancer prevention programmes aim to screen the largest possible proportion of women targeted by the national programme and ensure appropriate management for all those who have a positive or abnormal test result. Chapter 2 addresses programmatic considerations for cervical cancer prevention and control. 5.2.3. Benefits and risks of cervical cancer screeningWhile effective prevention programmes hold out the promise of dramatically decreasing the incidence of cervical cancer, any large-scale screening effort directed towards healthy populations can have both positive and negative outcomes. The primary positive outcome of screening is the reduction of cervical cancer by detecting and treating cases of pre-cancer before they progress to cancer. Additionally, screening can detect cervical cancer in women at an early stage when the cancer can still be successfully treated. Screening, by itself, has no actual preventive value. A link to treatment is essential. If such a link cannot be implemented then the screening programme is likely to have no impact on the incidence of cervical cancer. Positive outcomes in terms of the quality of the health-care facilities and services can also be achieved through implementation of a prevention programme; these may include improved infrastructure, updated training of health-care providers, increased awareness of women's reproductive health, and establishment of a quality control and quality assurance programme (see Chapter 2). One risk of screening, which applies to all screening tests described, is a variable rate of over-detection of pre-cancer (i.e. false-positive results), which leads to overtreatment of women who are in fact not at increased risk of invasive cancer at that time. Nevertheless, the benefits of detecting cervical pre-cancer early (i.e. true-positive results) – when treatment to prevent progression to cancer is available – far outweigh the relatively minor consequences to women caused by any of the treatment methods described. Another, more significant risk of screening is the risk of obtaining a false-negative result, which may result in missing signs of disease and thus a missed opportunity for treatment of pre-cancer or early cancer. Care must be taken to ensure that screening is performed only on the target population defined by the national programme, and that adequate resources are allotted to cover screening for 100% of these women along with the necessary follow-up. The screening programme also needs to assure there is a functioning referral system so that women who are found to have cancer will receive appropriate referral and management. 5.2.4. Characteristics of a good screening testA good screening test should be:
Top-level decision-makers must select which screening tests and treatments are to be implemented in a given setting. This selection should be made by considering the trade-offs between each test's performance, its capacity to be performed at each given level of the health system, its affordability and sustainability, and its potential for reaching the whole target population. This may result in, for example, choosing different tests for use at urban and rural sites. In theory, the best screening test is the one that has the lowest rate of false-negative results (i.e. when the result is negative/normal but the woman actually does have the disease), and simultaneously has the lowest rate of false-positives (i.e. when the result is positive but the woman actually has no abnormalities). False-negatives can lead to an increased risk of cancer if frequent screening is not available. False-positives can lead to overtreatment and increased anxiety for patients. In practice, it is important to choose the most appropriate screening test considering both the particular setting where the programme will be implemented and the human, financial and infrastructure resources available for using the chosen test. The test must be suitable for population-based screening programmes to ensure that it reaches the entire target population and not only those with greater access to health services. For long-term sustainability, the health system must have the capacity to maintain necessary equipment and to replace required supplies. Choosing the best test is a balance of all of these factors. 5.2.5. Screening age and frequencyWorld Health Organization (WHO) recommendations on target age and frequency of screening are based on current evidence available at the time of publication and on the natural history of HPV and cervical pre-cancer (see Chapter 1). High-risk HPV infections are very common in young women, but most of these infections are transient: they are eliminated spontaneously by the woman's body. Only a small percentage of all HPV infections that persist for many years may lead to invasive cancer. Cervical cancer usually develops slowly, taking 10–20 years from early pre-cancer to invasive cancer, so cervical cancer is rare before the age of 30. Screening younger women will detect many lesions that will never develop into cancer, which will lead to considerable overtreatment, and is thus not cost-effective. Cervical cancer screening should not start before 30 years of age. Screening women between the ages of 30 and 49 years, even just once, will reduce deaths from cervical cancer. Cervical cancer screening is recommended for every woman in this target age group, but this may be extended to younger ages if there is evidence of a high risk for CIN2+. Decisions about the target age group and frequency of screening are usually made at the national level on the basis of the local proportion of women with pre-cancer or cancer out of all women of the same age, the number of new cervical cancer cases recorded in the last two or three years, and the availability of resources and infrastructure, as well as other factors, such as HIV prevalence. To have the maximum impact in terms of reducing cervical cancer suffering and death, priority should be given to maximizing coverage1 and treatment rather than maximizing the number of screening tests in a woman's lifetime. This is true for all women regardless of HIV status. 1 “Coverage” refers to the proportion of women in the target age group who are screened at the recommended intervals during a given time period. The actual number of screening tests performed does not measure coverage, since this number may include women outside the target age, and women screened more often than recommended. Among women who test negative with visual inspection with acetic acid (VIA) or cytology, the interval for re-screening should be three to five years. Among women who test negative with HPV testing, re-screening should be done after a minimum interval of five years. After a subsequent screening with negative test results, and also for older women, the screening interval can be longer than five years. Women who have been treated for cervical pre-cancer should receive post-treatment follow-up after 12 months. a. Screening for women living with HIVRecommendations for women living with HIV:
Women living with HIV have a higher risk of having persistent HPV infections, and a higher risk of developing pre-cancer. In addition, women living with HIV are more likely to develop cervical cancer earlier and to die from it sooner. Because they develop pre-cancer at a younger age and the time for pre-cancer to progress to cancer can be shorter, women living with HIV are advised to follow a different screening schedule: after a negative screening test result, they should be re-screened within three years (see the screen-and-treat flowcharts for women living with HIV in Annex 9). Any of the three screening tests in this chapter (VIA, HPV test or cytology) can be used for women living with HIV, as can cryotherapy and loop electrosurgical excision procedure (LEEP) treatments. HIV screening is not mandatory for cervical cancer screening. However, in an area with high endemic HIV infection, women should be screened for HIV so that they know their status and, if positive, they should be counselled on the meaning of the test result and provided with appropriate treatment and follow-up care. In countries with a high prevalence of HIV, cervical cancer control services, as discussed in Chapter 2, would benefit patients most if there was two-way integration with HIV services; i.e. women receiving either HIV or cervical cancer screening services, if they were not already aware of their HIV status or had not had recent cervical cancer screening, could be routinely offered screening for the other disease. It is not uncommon for a woman to learn for the first time that she is HIV-positive at the time of attending for cervical cancer screening. 5.2.6. Ethical considerations for cervical cancer screening programmesDecisions on how best to use scarce resources to diagnose and treat cervical pre-cancer must consider the extent of disability and death caused by the disease and the likely success of an intervention to reduce the suffering and death associated with that disease versus using these scarce resources to prevent or control other illnesses. Cervical cancer, when seen through this lens, can cause a high burden of disability and death and the intervention (screening and treatment of pre-cancer) can prevent most of the disease. This makes cervical cancer prevention and control a rational and ethical choice for the use of available resources. While decisions about programmatic priorities are usually made at the national level, health-care providers should understand the reasons for the decisions, so that they are motivated to implement the programme in a cost-conscious manner and explain the priorities of the programme to their patients. Before a screening programme is implemented, the following elements should be considered to ensure an ethical and equitable approach:
a. Informed choice and informed consentInformed choice: The patient is given enough information so that she can make an informed choice about whether to accept or refuse the test or course of action proposed by providers. This information, which will be repeated and confirmed just before any intervention is conducted, needs to include (in the case of cervical cancer prevention) the meaning and consequences of a positive test, the availability of treatment, as well as the risks the patient may face should she refuse screening and related treatment. Informed consent: This refers to the explicit verbal or written permission given by a patient to receive a procedure or test, once she (or he) has received sufficient information to make an informed choice. Both informed consent and informed choice are based on the ethical principles of autonomy and respect for the individual. In many cultures, the notion of consent may be a collective decision-making process involving others, such as the husband/partner, family, and/or village leaders. Accurate information provided through health education and counselling can ensure that women and their extended families understand the facts about cervical cancer, including who is at risk, how screening can reduce this risk, and any potential harm related to screening or treatment. After receiving this information, it is the patient who makes the choice with advice and support from others in her close circle. The health-care provider needs to be conscious of the possibility that the patient may be subject to coercion and should make efforts to assure that the patient's decision is not coerced. See Practice Sheet 5.1 on obtaining informed consent. 5.2.7. Infection prevention for cervical cancer screening programmesIn all clinical activities, very careful attention should be given to infection prevention. Providers should use clean gloves on both hands when performing speculum or bimanual examinations, taking specimens, and performing procedures such as cryotherapy. For invasive procedures such as LEEP, providers should use sterile gloves. Guidelines on hand washing, handling of instruments and disposal of used supplies, including gloves, should be followed carefully to prevent the transmission of pathogens, including HIV. It is important to use standard infection prevention and control (IPC) precautions (see Annex 3) with all patients, regardless of whether they appear sick or well, or whether their HIV or other infection status is known or unknown. In this way, providers protect both their patients and themselves from infection. It is worthwhile to make infection prevention efforts visible to the woman being screened (such as washing hands and changing to fresh gloves), to reduce any anxiety she may have about safety and hygiene. 5.3. Screening methods for cervical pre-cancerUntil a few years ago, the only method of screening for cervical cancer was the Papanicolaou (“Pap”) smear or cytology. In high-income countries, where Pap smears have been used for population-based screening for over three decades, there has been a major reduction in morbidity and mortality from cervical cancer. However, population-based cytology screening in low- and middle-income countries is often unsuccessful because the financial investments to establish and maintain the necessary level of health infrastructure, including laboratory and skilled human resources, are not available or sufficient in many settings. Newer methods have been developed for cervical cancer screening: molecular HPV screening tests and visual inspection with acetic acid. These newer methods are described below, in addition to cytology-based screening methods. See also Practice Sheet 5.3 for important notes about screening methods. a. DescriptionMolecular HPV testing methods are based on the detection of DNA from high-risk HPV types in vaginal and/or cervical samples. Testing women younger than 30 years old for these viruses is not advised because many young women are infected with them, but most HPV infections will be spontaneously eliminated from their bodies before they reach the age of 30. Thus, HPV testing in women younger than this will detect many women with transient HPV infections and may subject them to unnecessary procedures and treatment which can cause harm, anxiety, discomfort and expense. However, as a woman ages, if high-risk HPV is detected, it is more likely that her HPV infection is persistent. Since persistent HPV infection is the cause of nearly all cases of cervical cancer, a positive test result in a woman over the age of 30 indicates that she may have an existing lesion or may be at risk for future pre-cancer and cancer (see Chapter 1, sections 1.3.4 and 1.3.5). Treating these screen-positive women can therefore greatly reduce the risk of future cervical cancer. HPV testing is being incorporated into cervical cancer prevention programmes in high-resource settings as a primary screening test. Currently the tests require transportation to and processing at a laboratory before results can be returned. But a new low-cost HPV test that can be processed on-site at the same facility where the sample is taken is being tested in several low-resource settings and will soon be available on the market. When planning to use a molecular screening test for HPV in a cervical cancer screening programme, it is important to use a standardized, clinically validated HPV test. Locally developed HPV tests are not appropriate unless they have been rigorously standardized and clinically validated. b. Who should be tested?For the reasons described above, HPV testing should be reserved for women over the age of 30, or the age specified in updated national guidelines. c. How to screenHPV testing does not necessarily require a pelvic examination or visualization of the cervix. A health-care provider can collect a sample of cells by inserting a small brush or other appropriate device deep into the vagina, and then placing it in a small container with an appropriate preservative solution. It may also be collected at the time of a speculum examination. The sample can also be self-collected by the woman; she can be given the brush and the special container and instructed how to use them. This strategy can be implemented at substantially lower cost to the health service and offers greater convenience to women. For further instructions on sample collection methods for HPV testing, see Practice Sheet 5.4. With the use of HPV testing as currently available, the specimen containers need to be transported to the laboratory for processing by a trained technician who then documents and returns the results. But new tests will soon allow for on-site processing. d. Strengths and limitationsHPV testing is highly sensitive for detecting HPV infection in women. However, while an HPV infection is a necessary precursor for cervical cancer, a positive HPV test does not confirm that the woman has pre-cancer; it only confirms that there is an HPV infection. Sample collection for HPV testing can be done at any health-care or community setting, as long as there is an appropriate laboratory within a reasonable distance, and reliable transport for specimens. At present, the need to process molecular HPV tests in a laboratory with a special clean room to avoid contamination and with equipment and reagents as specified by the manufacturers of the test as well as trained technicians can limit the utility of HPV screening in some settings. If there is no reliable method for processing and returning results to the patient within a reasonable time, this may present barriers to the use of HPV testing, in terms of cost and quality. The new low-cost HPV tests that will soon be available on the market will address this limitation because they can be processed at the clinic where samples are collected, using simpler equipment, and requiring less training to perform. 5.3.2. Visual screening methodsa. DescriptionVisual inspection with acetic acid (VIA) is a method for detecting early cell changes that are visible when using a speculum to inspect the cervix with the naked eye after applying dilute (3–5%) acetic acid to it.2 It requires training and supervision of primary care providers, as well as ongoing quality control and quality assurance. b. Who should be tested?VIA is appropriate to use in women whose squamocolumnar junction (SCJ) is visible, typically in those younger than 50 (see Chapter 1, section 1.2). This is because the SCJ gradually recedes into the endocervical canal when menopause occurs, making it possible to miss lesions when relying on visual inspection. c. How to screenVIA requires use of a speculum and light source, and a trained health-care provider. The provider performs a speculum examination, identifying the SCJ and carefully inspecting the cervix for visual signs suspicious for cancer or pre-cancer. A 3–5% acetic acid solution is liberally applied to the cervix with a large cotton swab. After removing the cotton swab, the provider waits for at least one minute, during which time any areas that became faintly white simply due to inflammation or physiological cell changes (metaplasia) will recede. Acetowhite changes on the cervix that do not recede after one minute are more likely to be associated with cervical pre-cancer or cancer. If these changes are seen in the transformation zone and have well-defined borders, they are considered a positive result (see Chapter 1, section 1.2.4, and/or the glossary, for a description of the transformation zone). If no persistent acetowhite changes are noted, a negative result is reported. For further information on VIA, see Practice Sheet 5.5.  Figure 5.1VIA results recorded on labelled drawingd. Strengths and limitationsVIA testing can detect both early changes and those representing more advanced pre-cancer. The immediate result allows the patient to be offered treatment at the same visit (i.e. the single visit approach). Alternatively, if the patient prefers not to do it immediately or if treatment is not available, then treatment can be done at a subsequent visit soon after. A diagnostic step, such as a colposcopy and/or biopsy, is usually not performed at this time (at the same screening facility), but if the cervix shows any unusual signs or the provider suspects cancer, the patient can be referred for further diagnosis. VIA is quite inexpensive, utilizes locally sourced supplies (vinegar and cotton), and does not rely on laboratory services. It can be performed by trained providers, with adequate visual acuity, at any level of the health system. Training can be accomplished in a few days using a competency-based approach. VIA is a subjective test and therefore depends on the skills and experience of the provider executing the test. Skills must be used regularly, and refresher courses are recommended. Due to the subjective nature of the test, quality control and quality assurance for VIA is particularly important. This can be achieved through supervision and routine monitoring. For more specific information consult the WHO/PAHO guide: Monitoring national cervical cancer prevention and control programmes: quality control and quality assurance for visual inspection with acetic acid (VIA)-based programmes (2013).3 5.3.3. Cytology-based screening methodsa. DescriptionCytology-based screening involves taking a sample of cells from the entire transformation zone (see Chapter 1, section 1.2.4, and/or the glossary for a description of the transformation zone). The cells are either fixed on a slide at the facility (Pap smear) or placed in a transport medium (liquid-based cytology) and then sent to the laboratory where expert cytotechnologists examine the cells under a microscope. If abnormal cells are seen on microscopic examination, the extent of their abnormality is classified using the Bethesda System (see Annex 5). A cytology-based screening programme can use one of the two available methods: the conventional Pap smear (or Pap test) or liquid-based cytology (LBC). With conventional cytology, a sample of cells is smeared on a glass slide, and preserved by a fixative agent. LBC was introduced in the mid-1990s; it is a refinement of conventional cytology and is increasingly being used in high- and mid-resource settings. For LBC, instead of smearing the sample onto a slide, it is placed in a container of preservative solution and sent to the laboratory for microscopic examination. b. Who should be tested?Cytology-based screening can be used with women in the target population for screening (see section 5.2.5 earlier in this chapter). c. How to screenCollection of a cytology sample requires a speculum and adequate lighting to visualize the entire surface of the cervix. The provider takes specimens from the face of the cervix and the endocervix using a spatula or brush and transfers the specimen to a slide (Pap smear) or a preservative solution (LBC). The sample must be appropriately labelled and transported to the laboratory, where skilled personnel are needed to process and interpret it (see Practice Sheet 5.6 for further instructions). d. Strengths and limitationsWell-implemented cytology programmes can successfully prevent cervical cancer. However, cytology programmes require multiple steps and face significant challenges, especially in low-resource settings. The specimen must be properly collected, fixed/preserved, safely delivered to the laboratory, accurately processed and interpreted, and the results reliably delivered back to the provider. The patient needs to receive the results and have the necessary follow-up or treatment. Hence, there are many opportunities for logistical challenges to interfere with a successful screening programme. Liquid-based cytology has some advantages over conventional methods. The specimens obtained are more representative of the areas sampled, and there is generally a lower rate of unsatisfactory specimens and a reduced likelihood of inflammatory or blood cells obscuring the cells that need to be examined on a slide. Furthermore, each specimen takes less time to interpret, and the material collected can also be tested for HPV DNA and other STIs. However, this is a costly technique requiring advanced technology, including a sophisticated laboratory and highly trained technicians. Present evidence does not demonstrate that LBC is any more effective in reducing cancer morbidity and mortality than conventional cytology. Cytology-based screening, as for all screening methods, requires a well-functioning quality control and quality assurance programme (see Chapter 2 for more information on continuous quality assurance, especially section 2.2.4 on programme monitoring and evaluation). 5.3.4. Comparison of cervical pre-cancer screening methodsTable 5.1 provides a summary and comparison of the procedures, strengths and limitations of the three screening methods for cervical pre-cancer (molecular, visual and cytology-based methods), including both cytology-based methods: Pap smear and LBC. Table 5.1Comparison of the characteristics of screening methods for cervical pre-cancer. See Practice Sheet 5.7 on counselling women after positive screening test results. See Sample Forms 11.1 and 11.2 in Annex 11, relating to screening test results, follow-up and repeat screening. 5.4. Diagnostic tests for detection of cervical pre-cancer5.4.1. The role of diagnostic testsA diagnostic or confirmatory test is a medical test performed to aid in the diagnosis or detection of a disease. Because not all women with positive results on cervical screening tests actually have pre-cancer, a subsequent diagnostic test is sometimes used for definitive diagnosis or confirmation of pre-cancer or cancer. Diagnostic tests have major resource implications. They can create significant barriers for women to access services, potentially delaying treatment, and/or increasing the numbers of women who are lost to follow-up and who therefore may never receive treatment for their pre-cancer. Moreover, diagnostic tools can produce false-positive and false-negative results, thus muddying rather than clarifying patient management. Diagnostic tests should not be required before treatment for pre-cancer where the resources are not available or in settlings where there are high rates of loss to follow-up. 5.4.2. Diagnostic tools, training and facilitiesColposcopy, biopsy and endocervical curettage (ECC) are the most commonly used diagnostic tests for cervical pre-cancer. They require a high level of resources and training. If a colposcope, biopsy forceps and an endocervical curette are available, these procedures may be provided at the primary care level by physicians and mid-level providers who have had competency-based training and appropriate supportive supervision. More often, they are performed as outpatient procedures at the secondary care level (district hospital). 5.4.3. ColposcopyColposcopy is the examination of the cervix, vagina and vulva with an instrument that provides strong light and magnifies a field, allowing specific patterns in the epithelial (surface) layer and surrounding blood vessels to be examined. This can be done with a colposcope, an expensive, specialized piece of equipment (see Figure 5.2). More recently, it has also been accomplished using specially designed video or digital cameras. Typically, colposcopy is used on patients with positive screening results, to verify the presence, extent and type of pre-cancer or cancer, to guide biopsies of any areas that appear abnormal, and to help determine whether cryotherapy or LEEP is the most appropriate treatment. Colposcopy requires highly trained providers and is not an appropriate screening tool, nor is colposcopy a required step between screening and treatment (see Practice Sheet 5.8 on colposcopy). 5.4.4. BiopsyBiopsy is the removal of small samples of abnormal tissue for microscopic examination to achieve a diagnosis. Biopsies can be taken from areas of the cervix that are VIA-positive or from areas that appear suspicious for cancer. If a lesion or abnormal structure of the cervix is not visible to the naked eye, colposcopy can assist in pinpointing the site or sites where one or more biopsies should be taken. Typically, a biopsy is taken from each abnormal area, although random biopsies may be useful under certain circumstances. Special biopsy forceps are required (see Figure 5.3), and training is necessary. Biopsy is used to determine the degree of abnormality of the cell changes at the cervix and to rule out cancer. After examination, a biopsy is classified as normal, as cervical intraepithelial neoplasia (CIN), or as invasive carcinoma. In some settings, precancerous lesions are classified as low-grade (CIN1) or high-grade (CIN2 and CIN3, collectively referred to as CIN2+) pre-cancer. The classification is based on the thickness of the abnormal epithelium: the deeper the abnormal cells reach from the basement membrane toward the upper layer of cells, the higher the degree of CIN (see Figure 1.12 in Chapter 1, section 1.3: Natural history of cancer of the cervix, for a graphic depiction of CIN abnormalities). The degree of abnormality informs recommendations for treatment: high-grade lesions (CIN2+) are moderate or severe pre-cancer and are treated, whereas CIN1 is a mild abnormality that typically represents an infection with a low-risk HPV type rather than a true precursor to cervical cancer, and so CIN1 is not usually treated. If invasive cancer is found on biopsy, the patient should be referred for treatment (see Chapter 6). Using biopsy as a diagnostic tool requires the ability to transport biopsy specimens and the availability of a laboratory and skilled technicians to process and interpret the results, as well as the ability of the patient to return for the results and for the recommended management or treatment. It also requires an ongoing quality control and quality assurance programme to maintain a high level of accuracy in the processing and interpretation of the tissue samples (see Practice Sheet 5.9 on biopsy and ECC). 5.4.5. Endocervical curettageEndocervical curettage (ECC) is a simple procedure that takes just a few minutes: some surface cells are gently scraped from the endocervical canal with a special thin instrument or spatula, and the tissue is placed in a container with a fixative solution and sent to a laboratory for examination. ECC is used in the following circumstances: (1) rare cases when the screening test suggests there may be a pre-cancer or cancer that is not visible with colposcopy, leading the provider to suspect that the lesion is hidden inside the cervical canal; (2) if the squamocolumnar junction cannot be fully visualized in the face of an already suspected lesion; (3) if the Pap smear revealed a glandular lesion, which usually arises from the columnar epithelium inside the canal; and (4) if screening and/or colposcopy were not adequate because the transformation zone was not seen in its entirety and cancer is suspected. In many locations, an endocervical cytobrush specimen may be used as an equivalent approach instead of ECC (see Practice Sheet 5.9). As previously noted for biopsies, after performing an ECC, transport of the specimen, interpretation, and communication of the results to the patient are vital to successful programmes. The provider needs to inform the patient when the results will be ready and ask her to return as soon as feasible to discuss the results. At this return visit, based on the biopsy and/or ECC results, treatment options should be discussed and performed immediately, if possible. Women who do not return as requested should be contacted, given their results and advised about what, if any, treatment they need. See Chapters 3, 6 and 7 for additional information about counselling, providing a woman with positive biopsy results, and ensuring that she receives appropriate management or referral. 5.4.6. Special situations related to colposcopy, biopsy and endocervical curettagea. The entire transformation zone is not visibleIn this case, ECC should be performed. If this is not possible, and the screening test revealed a possible high-grade lesion, then women should be referred for LEEP or cold knife conization (CKC). In postmenopausal women, the entire transformation zone may not be visible. b. The woman is pregnantPregnancy is not the ideal time to perform a screening test. However, if a screening test is done during pregnancy and abnormal results are found, or if a lesion is noted on speculum examination, the patient should be referred for colposcopy. Taking biopsies during pregnancy can cause significant bleeding. Therefore, if colposcopy is not suspicious for invasive cancer, the patient can be given an appointment to return at 6–12 weeks postpartum for colposcopic re-evaluation and possible biopsy. If cancer is suspected, she should be referred immediately to a specialist at a tertiary care hospital. c. The woman is living with HIVManagement of abnormalities, including colposcopy and biopsy, should not be modified on the basis of a woman's HIV status. During the healing process after any procedure, women living with HIV might have increased viral shedding. In counselling, it is very important for the provider to stress that the patient should discuss this with her partner(s) and abstain from intercourse until healing has occurred. 5.4.7. Comparison of methods for diagnosis of cervical pre-cancerTable 5.2 provides a summary and comparison of the procedures, strengths and limitations of the three diagnostic methods for cervical pre-cancer: colposcopy, biopsy and ECC. Table 5.2Comparison of the characteristics of diagnostic methods for cervical pre-cancer. See Sample Forms 11.3 and 11.4 in Annex 11, relating to diagnostic evaluations. 5.5. Treatment options for cervical pre-cancerWomen with pre-cancer must receive effective treatment, which can usually be provided by trained primary care providers at primary care facilities (i.e. health centres), in contrast to treatment for suspected or confirmed invasive cancer, which requires specialist medical providers at higher-level facilities (i.e. hospitals). In the context of a screen-and-treat approach, treatment follows a positive screening test without diagnostic confirmation. Treatment aims to destroy or remove areas of the cervix identified as pre-cancer. Treatment methods may be ablative (destroying abnormal tissues by burning or freezing) or excisional (surgically removing abnormal tissues). With ablative methods, no tissue specimen is obtained for further confirmatory histopathological examination. Each treatment method has eligibility criteria that should be met before proceeding with treatment. In this section, we will discuss use of cryotherapy, loop electrosurgical excision procedure (LEEP) and cold knife conization (CKC). Other forms of therapy do exist, such as laser excision or ablation, but are not as widely available and thus will not be addressed here. Hysterectomy is rarely an appropriate means to treat pre-cancer. Unless there are other compelling reasons to remove the uterus, hysterectomy should not be performed for pre-cancer. The choice of treatment will depend on:
Regardless of the treatment method recommended by the provider, the woman needs information about the procedure so that she can make an informed choice. Consent from the patient is needed prior to the procedure, but it can be given verbally (see Practice Sheet 5.1). If cancer is suspected: If a patient has a cervical abnormality that looks suspicious for cancer, the patient should NOT be treated with cryotherapy, LEEP or CKC. The appropriate next step for her is a cervical biopsy to confirm or rule out a diagnosis of cancer (see Chapter 6). If the provider has the appropriate training and equipment, he or she can perform the biopsy. If not, the provider should refer the patient for prompt further evaluation. 5.5.1. CryotherapyCryotherapy eliminates precancerous areas on the cervix by freezing (an ablative method). It involves applying a highly cooled metal disc (cryoprobe) to the cervix and freezing the abnormal areas (along with normal areas) covered by it (see Figure 5.4). The supercooling of the cryoprobe is accomplished using a tank with compressed carbon dioxide (CO2) or nitrous oxide (N2O) gas. Cryotherapy can be performed at all levels of the health system, by health-care providers (doctors, nurses and midwives) who are skilled in pelvic examination and trained in cryotherapy. It takes about 15 minutes and is generally well tolerated and associated with only mild discomfort. It can, therefore, be performed without anaesthesia. Following cryotherapy, the frozen area regenerates to normal epithelium. Figure 5.4Position of cryoprobe on the cervix and ice forming. Eligibility criteria: Screen-positive women (such as with VIA screening) or women with histologically confirmed CIN2+ are eligible for cryotherapy if the entire lesion and squamocolumnar junction are visible, and the lesion does not cover more than three quarters of the ectocervix. If the lesion extends beyond the cryoprobe being used, or into the endocervical canal, the patient is not eligible for cryotherapy. The patient is not eligible for cryotherapy if the lesion is suspicious for invasive cancer. Post procedure: It takes a month for the cervical tissue to regenerate. The patient should be advised that during this time she may have a profuse, watery discharge and she should avoid sexual intercourse until all discharge stops, or use a condom if intercourse cannot be avoided. For further information on cryotherapy, see Practice Sheet 5.10 and consult WHO guidelines: use of cryotherapy for cervical intraepithelial neoplasia (2011).4 5.5.2. Loop electrosurgical excision procedureLEEP is the removal of abnormal areas from the cervix using a loop made of thin wire powered by an electrosurgical unit. The loop tool cuts and coagulates at the same time, and this is followed by use of a ball electrode to complete the coagulation (see Figure 5.5). LEEP aims to remove the lesion and the entire transformation zone. The tissue removed can be sent for examination to the histopathology laboratory, allowing the extent of the lesion to be assessed. Thus, LEEP serves a double purpose: it removes the lesion (thus treating the pre-cancer) and it also produces a specimen for pathological examination. The procedure can be performed under local anaesthesia on an outpatient basis and usually takes less than 30 minutes. However, following LEEP, a patient should stay at the outpatient facility for a few hours to assure bleeding does not occur. Figure 5.5LEEP of an ectocervical lesion with one pass: excision of the lesion with wire electrode and coagulation with ball electrode. LEEP is a relatively simple surgical procedure, but it should only be performed by a trained health-care provider with demonstrated competence in the procedure and in recognizing and managing intraoperative and postoperative complications, such as haemorrhage; e.g. a gynaecologist. LEEP is best carried out in facilities where back-up is available for management of potential problems; in most cases, this will limit LEEP to at least the secondary-level facilities (i.e. district hospitals). Eligibility criteria: Screen-positive women (such as with VIA screening), or women with histologically confirmed CIN2+ are eligible for LEEP if the lesion is not suspicious for invasive cancer. Post procedure: The patient should be advised to expect mild cramping for a few days and some vaginal discharge for up to one month. Initially, this can be bloody discharge for 7–10 days, and then it can transition to yellowish discharge. It takes one month for the tissue to regenerate, and during this time the patient should avoid sexual intercourse or use a condom if intercourse cannot be avoided. See Practice Sheet 5.11 for further details on LEEP. 5.5.3. Cold knife conizationCKC is the removal of a cone-shaped area from the cervix, including portions of the outer (ectocervix) and inner cervix (endocervix) (see Figure 5.6). The amount of tissue removed will depend on the size of the lesion and the likelihood of finding invasive cancer. The tissue removed is sent to the pathology laboratory for histopathological diagnosis and to ensure that the abnormal tissue has been completely removed. A CKC is usually done in a hospital, with the necessary infrastructure, equipment, supplies and trained providers. It should be performed only by health-care providers with surgical skill – such as gynaecologists or surgeons trained to perform the procedure – and competence in recognizing and managing complications, such as bleeding. The procedure takes less than one hour and is performed under general or regional (spinal or epidural) anaesthesia. The patient may be discharged from hospital the same or the next day. Figure 5.6Removal of a cone-shaped area of the cervix. Eligibility criteria: CKC should be reserved for cases that cannot be resolved with cryotherapy or LEEP. It should be considered in the presence of glandular pre-cancer or microinvasive cancer lesions of the cervix (see Chapter 6). Post procedure: Following CKC, patients may have mild cramping for a few days and a bloody vaginal discharge, transitioning into a yellow discharge for 7–14 days. It takes 4–6 weeks for the cervix to heal (depending on the extent of the procedure) and during this time the patient should avoid sexual intercourse or use a condom if intercourse cannot be avoided. See Practice Sheet 5.12 for more information on CKC. 5.5.4. Comparison of methods for treatment of cervical pre-cancerTable 5.3 provides a summary and comparison of the procedures, strengths and limitations of the three treatment methods for cervical pre-cancer: cryotherapy, LEEP and CKC. Table 5.3Comparison of the characteristics of treatment methods for cervical pre-cancer. 5.6. Possible complications and follow-up after treatment5.6.1. Possible complicationsAll three treatment modalities may have similar complications in the days following the procedure. All of these complications may be indications of continuing bleeding from the cervix or vagina or an infection that needs to be treated. See Annex 12 for information on treatment of cervical infections and pelvic inflammatory disease. Patients should be advised that if they have any of the following symptoms after cryotherapy, LEEP or CKC, they should seek care at the closest facility without delay:
5.6.2. Follow-up after treatmentA follow-up visit including cervical cancer screening is recommended 12 months after treatment to evaluate the woman post-treatment and detect recurrence. If this follow-up rescreen is negative, the woman can be referred back to the routine screening programme. An exception is if the patient has a histopathological result at the time of treatment that indicates CIN3 or adenocarcinoma in situ (AIS) based on a specimen from LEEP or CKC. In this case, rescreening is recommended every year for three years. If these rescreens are negative, she is then referred back to the routine screening programme. If the patient treated for pre-cancer has a positive screen on her follow-up visit (indicating persistence or recurrence of cervical pre-cancer), retreatment is needed. If the initial treatment was with cryotherapy, then retreatment should be performed using LEEP or CKC, if feasible. If a histopathological result from a specimen obtained from a punch biopsy, LEEP or CKC procedure indicates cancer, it is critical that the patient be contacted and advised that she must be seen at a tertiary care hospital as soon as possible. 5.7. Linking screening and treatment in practiceFor cervical cancer prevention to be effective, positive screening must be linked with effective treatment. WHO has considered the evidence for two approaches to linking screening and treatment for pre-cancer of the cervix:
5.7.1. Screen, diagnose and treat approachThe approach involves conducting the screening test and following up on a positive result by using diagnostic steps, such as colposcopy and biopsy, to histologically confirm the pre-cancer diagnosis and its severity. Treatment is then based on the results of the histological confirmation. For example, if a woman has histologically confirmed CIN2+, she receives treatment (see section 5.5 and Box 5.1), but if cancer is found on histology, she is referred to the tertiary care hospital (see Chapter 6). Box 5.1Summary treatment recommendations. The expert panel recommends (STRONG recommendation): Use cryotherapy over no treatment. a. Recommendations for treatment in the screen, diagnose and treat approachBox 5.1 presents WHO's evidence-based summary treatment recommendations for histologically confirmed CIN2+. These recommendations have been derived from WHO guidelines for treatment of cervical intraepithelial neoplasia 2–3 and adenocarcinoma in situ (2014) – please see that publication for the complete recommendations with remarks and considerations.5 These recommendations are meant for health-care providers and to assist programme managers in designing cervical cancer prevention and control strategies. 5.7.2. Screen-and-treat approachAdding a diagnostic step after screening, before treatment of pre-cancer, can result in high loss to follow-up because additional patient visits are required as well as a longer time interval between screening and treatment. To reduce such loss to follow-up, the screen-and-treat approach has been developed and this strategy is increasingly being adopted worldwide. The screen-and-treat approach utilizes a screening test that gives either immediate or rapid results that can be followed closely by treatment of those women who screen positive for pre-cancer. Ideally, the treatment can occur on the same day and at the same location (i.e. the single visit approach). If this is not possible or the patient declines, then treatment can be offered shortly after screening at an arranged time and location easily accessible to the patient. The screen-and-treat approach eliminates the extra visits and time required for the diagnostic step. A limitation to the screen-and-treat approach is that the lack of a diagnostic step can result in false-positive results and overtreatment. However, concerns about overtreatment must be weighed against the low morbidity associated with treatment using cryotherapy and the overall benefit of ensuring higher rates of treatment. Another concern about the screen-and-treat approach is that when cryotherapy is done immediately after positive VIA or HPV results, no tissue sample would be available if needed for histological examination at a later time. To try to reduce overtreatment while still retaining the benefits of the screen-and-treat approach, another strategy is to follow an initial positive screening test with a second test, and then only treat the patient if both tests are positive. For instance, when HPV testing is used as a single screening test in a screen-and-treat approach, women who have a positive HPV test will be treated. Some of these women with a positive HPV test had pre-cancer and were appropriately treated, but some did not have pre-cancer and hence were unnecessarily treated (overtreatment). In a strategy that uses a second test, such as VIA, a woman who is HPV positive would then undergo VIA, and would only be treated if the VIA is also positive. If the VIA is negative, she would not be treated, but would be followed up with another HPV test in 12 months. However, adding a second test does not always result in a better outcome, since false-negative results can occur on the second test. If the first test was in fact a true positive and the second test was a false negative, then the woman would not be treated even though she had pre-cancer. Hence the use of a second test must be carefully considered. In the case of an initial test being positive and a second test being negative, another screen 12 months later may be recommended. a. Recommendations for treatment in the screen-and-treat approachThe following recommendations for screening and treatment of pre-cancer of the cervix have been derived from the WHO guidelines for screening and treatment of precancerous lesions for cervical cancer prevention (2013).6 These recommendations are to help health-care providers understand, explain and treat pre-cancer and to assist programme managers in designing cervical cancer prevention and control programmes. Easy-to-follow screen-and-treat algorithms are available as flowcharts in Annexes 7–9 and detailed recommendations are in the full published guidelines, available online. Box 5.2 presents WHO's evidence-based screen-and-treat summary recommendations, which should be used when making case management decisions. Please see the full publication for the complete recommendations with remarks and considerations. Box 5.2Screen-and-treat strategy summary recommendations. These recommendations apply to all women regardless of HIV status, but specific recommendations for women living with HIV have also been developed (see Annex 9). The expert panel recommends against the (more...) Programme managers should also consult Chapter 2, which contains information about many other factors to consider when creating a cervical cancer prevention and control programme. 2 Acetic acid is a component of almost all vinegars; vinegar with 3–5% acidity must be used to correctly detect positive lesions. 3456Which term describes the removal of a coneCervical diagnostic excisional procedures (also known as conization or cone biopsy) refer to the excision of a cone-shaped portion of the cervix surrounding the endocervical canal and including the entire transformation zone.
Which diagnostic test is the direct visual examination of the tissue of the cervix and vagina?Colposcopy is a diagnostic procedure in which a colposcope (a dissecting microscope with various magnification lenses) is used to provide an illuminated, magnified view of the cervix, vagina, vulva, or anus.
What term means an inflammation of the mucous membrane lining of the cervix?Cervicitis. Cervicitis is the term used to denote the inflammation involving the columnar epithelium of the cervix. It results in congestion of underlying connective tissue, desquamation of cells and ulceration with mucopurulent discharge.
Which term is also known as parturition?Parturition means childbirth. Childbirth is the culmination of pregnancy, during which a baby grows inside a woman's uterus. Childbirth is also called labor.
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Which term describes the removal of a cone-shaped specimen of tissue from the cervix?
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