Prevention of cervical cancer

This article reviews the burden of cervical cancer in South Africa and shows that it remains the most common cancer among South African women, particularly women with least access to cervical cancer screening. It explains the rationale behind the South African cervical cancer screening policy, which is to offer all asymptomatic women three free cervical smears in a lifetime, beginning at age 30, 10 years apart. Further, it illustrates that cervical cancer screening offers unique opportunities for prevention at both the primary and secondary levels. The causal association of human papillomavirus infection of the cervix and the possibility for vaccination against the virus is discussed. The history of screening in South Africa and why it has failed to make a major impact to date on the morbidity and mortality of cervical cancer is also discussed. Finally, possible alternative approaches to cervical cytology for the prevention of cervical cancer are briefly reviewed.     

Human papillomavirus,cervical screening and ethical considerations

Human papillomavirus (HPV) is an extremely prevalent virus linked to multiple cancers, but most notably cervical cancer. The cervical screening programme in the UK has developed significantly since it was first introduced in 1964. This, together with the introduction of HPV vaccination, has made a huge difference to the early diagnosis and mortality for cervical cancer patients. Uptake of screening is paramount and this article addresses the barriers to this, and how these might be overcome. Other ethical issues around the topic of HPV, vaccination and screening include discrimination around sexual behaviour and orientation, education, vaccination availability and vertical transmission. This is an area of medicine that continues to develop and evolve as we understand more about HPV and how to tackle it.     

基因甲基化检测在宫颈癌筛查中的临床应用

宫颈癌是常见的恶性肿瘤之一,严重威胁女性健康,高危型人乳头瘤病毒(HPV)持续感染是引起宫颈癌的主要原因.宫颈基因甲基化程度随宫颈病变程度的增加而增加,为宫颈癌早期筛查提供了新的方法.宫颈癌的早期发现、早期诊断和早期治疗是降低死亡率并提高生存率的关键.应用宫颈癌基因甲基化检测对于降低阴道镜转诊率、减少患者过诊过治、节约...     

Reducing the burden of glandular carcinomas of the uterine cervix

Widespread use of the Papanicolaou test for the screening of cervical cancers has lead to a significant decline in overall incidence and mortality rates over the past 3 decades. When different histologic types of cervical cancers are considered and trends are reexamined, it becomes apparent that observed declines are reflective of squamous cell carcinomas predominantly; the rates for adenocarcinomas continue to rise. This rise in incidence may be due to the greater difficulty in screening for glandular precursor lesions that often arise high within the endocervical canal. Reducing the incidence and mortality rates that are associated with adenocarcinomas can be accomplished by using improved screening techniques and large-scale implementation of cervical cancer vaccines that target the predominant oncogenic human papillomavirus types that are associated with adenocarcinoma.     

Screening for gynaecological conditions

Well-organized cervical screening programmes have reduced the mortality from cervical cancer by up to 50% in the developed world. Despite the successful development of human papillomavirus vaccines there is likely to remain a need for cervical screening for the foreseeable future. In contrast, the value of mass screening for other gynaecological cancers remains unproven, although current screening methods can detect early stage ovarian cancer in asymptomatic individuals. Breast screening does appear to be associated with a reduction in mortality in women aged 50–69 years but disagreement remains about its value in younger and older women. Testing for sexually transmitted infections is effective in reducing morbidity but tends to be selective at present because of concerns over the cost and psychosocial implications of general population screening.     

老年女性子宫颈癌筛查及子宫颈病变的处理

老年女性仍有较高的罹患子宫颈癌的风险,受多种因素致其子宫颈癌筛查不足且缺乏专门针对老年女性的筛查及处理指南,现行的子宫颈癌筛查指南中对不能满足停筛条件的老年女性,由于存在患病的风险,应当继续进行筛查,已达成共识。目前,那些满足停筛条件的老年女性,65岁为其终止筛查年龄的建议受到了争议。对于老年女性的子宫颈癌筛查及子宫颈病变的处理应注意充分利用机会性筛查,且在进行阴道镜检查及活检时应充分考虑到老年女性的特殊性,对于老年性阴道炎明显患者可在检查前2周局部使用雌激素;不满意的阴道镜检查时应利用特殊的暴露及活检技巧等。文章通过复习文献并结合自身经验成文,以期对临床老年女性子宫颈癌的筛查和子宫颈病变的处理提供帮助。     

Secondary prevention of cervical cancer

Cervical cancer affects women in their reproductive ages. Screening is an important secondary prevention strategy. The long process of carcinogenic transformation from human papillomavirus (HPV) infection to invasive cancer provides ample opportunities to detect the disease at a stage when treatment is highly effective. Suitable screening tests are cytology, visual inspection after acetic acid application and HPV detection tests. Evidence of effectiveness of the tests to reduce cervical cancer mortality and the cost-effectiveness of screening programs have been demonstrated. Cervical intraepithelial neoplasia grade 2 and grade 3 are the high-grade cervical cancer precursors and need to be treated. Treatment is safe and effective with ablative or excisional techniques. The World Health Organization recommends screening women at least once in a lifetime between 30 and 49 years of age and ensuring effective treatment of the detected abnormalities. Combination of HPV vaccination and population-based screening will be instrumental in eliminating cervical cancer.     

The combined impact of implementing HPV immunisation and primary HPV screening in New Zealand: Transitional and long-term benefits,costs and resource utilisation implications

BackgroundIn response to emergent evidence, many countries are transitioning from cytology-based to HPV screening. We evaluated the impact of an upcoming transition on health outcomes and resource utilisation in New Zealand.MethodsAn extensively validated model of HPV transmission, vaccination, natural history and cervical screening (‘Policy1-Cervix’) was utilised to simulate a transition from three-yearly cytology for women 20–69 years to five-yearly HPV screening with 16/18 genotyping for women 25–69 years, accounting for population growth and the impact of HPV immunisation. Cervical cancer rates, resources use (test volumes), costs, and test positivity rates from 2015 to 2035 were estimated.FindingsBy 2035, the transition to HPV screening will result in declines in cervical cancer incidence and mortality rates by 32% and 25%, respectively, compared to 2018. A potentially detectable 5% increase in cervical cancer incidence due to earlier detection is predicted for the year of transition. Annual numbers of women screened will fluctuate with the five-year screening interval. Cytology volumes will reduce by over 80% but colposcopy volumes will be similar to pre-transition rates, and program costs will be reduced by 16%. A 9% HPV test positivity rate is expected in the first round of HPV screening (2019–2023), with 2.7% of women referred for colposcopy. Transitioning from cytology to primary HPV cervical screening could avert 149 cancer cases and 45 deaths by 2035.ConclusionPrimary HPV screening and vaccination will reduce cervical cancer and resources use. A small transient apparent increase of invasive cancer rates due to earlier detection may be detectable at the population level, reflecting the introduction of a more sensitive screening test. These findings can be used to inform health services planning and public communications surrounding program implementation.     

Incorporating human papillomavirus testing into cytological screening in the era of prophylactic vaccines

Screening for, and treatment of, pre-cancerous cervical lesions has lead to dramatic reductions in cervical cancer in many countries. In all cases, cervical screening has been based on cytology, but that is beginning to change. Research studies, including randomised trials, clearly show that human papillomavirus (HPV) testing could be used to prevent a greater proportion of cervical cancer within a practical screening programme. Meanwhile, young adolescents are being vaccinated against HPV in developed countries, but cervical screening should continue for many years because it will take decades before most of those targeted by screening have been vaccinated. In the HPV vaccination era, the rate of cervical disease will decrease, and so will the positive predictive value of cytology. The screening characteristics of HPV testing make it the preferred choice for primary screening. However, questions regarding how to use HPV testing to screen vaccinated and unvaccinated women in the future remain unanswered.     

Social inequality in Pap smear coverage: identifying under-users of cervical cancer screening in Argentina

In Argentina, the unequal distribution of the burden of cervical cancer is striking: the mortality rate of the province of Jujuy (15/100,000) is almost four times higher than that of the city of Buenos Aires (4/100,000). We aimed to establish the socio-demographic profile of women who were under-users of Pap smear screening, based on an analysis of a representative sample of Argentinean women from the First National Survey on Risk Factors in 2005. We found that in Argentina, women who are poor, unmarried, unemployed or inactive, with lower levels of education and reduced access to health care, and women over the age of 65, were under-users of screening. Screening must not remain opportunistic. Strategies must incorporate the needs and perceptions of socially disadvantaged women, and increase their access to screening. Of utmost importance is to provide good quality screening and treatment services that reach women who are at risk. Pilot projects using new, alternative technologies should be encouraged in less developed parts of the country. Promotion among health professionals of the scientific basis and effectiveness of each screening modality is essential to reduce wasteful practices such as annual screening and screening of young women that waste resources and fail to reduce cervical cancer incidence and mortality rates.     

Knowledge of cervical cancer and screening among women in east-central England

Abstract.   Philips Z, Avis M, Whynes DK. Knowledge of cervical cancer and screening among women in east-central England. Int J Gynecol Cancer 2005; 15: 639–645.
This study assesses the extent and accuracy of women's knowledge of cervical cancer, risk factors, and the efficacy of the national screening program. Data were obtained from a questionnaire survey of randomly selected women eligible for screening, drawn from a population in east-central England. The majority of women in the sample overestimated the current incidence of cervical cancer, both absolutely and relative to other cancers. Perceiving incidence to be high was associated with reporting worries about the disease. With respect to the screening process, 78.3% believe that the smear abnormality rate is higher than it actually is, and only 7.6% correctly appreciate that the abnormality rate is highest at younger ages. With respect to performance, 16.3% believed the smear test to be completely accurate, and more than half overestimated the likely number of cancer cases prevented by screening. While certain cervical cancer risk factors were correctly assigned by the majority of women, undue emphasis was placed on genetic influence, while the risks posed by human papillomavirus infection were unfamiliar to almost half of the sample. We conclude that women typically possess only a partial picture of risk factors and overestimate both the incidence of cervical cancer and the efficacy of screening.     

Current perspectives in cervical cancer

Cervical cancer is a Public Health problem among women worldwide, especially in the developing world. The understanding of the HPV association with the high-grade squamous intraepithelial lesions and cervical cancer and the knowledge of the pre-invasive lesions natural history have strengthened the justification of different means of cancer prevention and screening programs, the application of different pre-invasive lesion treatments and particularly advances in conventional treatments of cervical cancer. In the last thirty years, cervical cancer's incidence and mortality rates have decreased in more than 75% in developed nations due to efficient application of secondary prevention based on cytology and colposcopy screening programs plus to in-office implementation of precursor lesions treatment methods. In the developing nations, these achievements can be obtained using specific steps of primary prevention, massive participation of risk patients in screening programs and improving ambulatory application of pre-invasive cervical lesion treatments. In Mexico several indicators suggest that this condition has began. New knowledge paradigms of the local immune response to HPV-cervical cancer pre-invasive and invasive lesions are being added to the construction of new preventive and therapeutic anti-cancer strategies. The preventive vaccines anti-high risk oncogenic-HPVs offer a good perspective in short term, also the use of different cellular immunotherapy strategies anti-cervical cancer as adyuvant of conventional treatments offer an encouraging panorama in not long term. In the next years, the improving of specific genes determination and their correlation with biologic features of the specific tumor which are involved on pre-invasive and invasive stages of cervical cancer will raise the understanding and the treatment of these patients.     

Cervical cancer screening: state of the art

PURPOSE OF REVIEW: The objective of cervical cancer screening is to prevent the occurrence of and death from cervical cancer by detecting and treating high-grade squamous intraepithelial lesions. A significant decline in occurrence and mortality from cervical cancer in developed countries has been associated with the application of organized cervical screening programs. The use of the available local health methods in cervical cancer screening can be adjusted in different countries. This review discusses the recent results in traditional and alternative cervical cancer screening. RECENT FINDINGS: The current recommendations of both the American Cancer Society and the American College of Obstetricians and Gynecologists concerning clinical practice guidelines for cervical cancer screening are commented upon. New methods and new technology for cervical cancer screening are described. Attributable failure factors in the screening process, particularly in the coverage, are analyzed. A critical assessment of the suitability of local cervical cancer screening resources is discussed. SUMMARY: Screening is clearly a complex multifactorial process, not a test. Nowadays, with the human papillomavirus vaccine on the horizon, screening is the best strategy for cervical cancer control. Good screening programs, with high coverage, quality control and follow-up included, are the basis of obtaining better results. The Papanicolaou test and its variants are the best methods of cervical cancer screening in high-resource settings. Alternative visual inspection using cervical dyes could be the most useful method in low-resource settings. The challenge for the future may be less of a technical nature and more dependent on local finances and screening policies.     

宫颈癌机会性筛查的应用与探讨

目的:探讨宫颈癌机会性筛查的应用及意义。方法:为2008年1月~12月在新疆自治区人民医院妇产科门诊就诊的患者行机会性筛查,以液基细胞学、HPV检测和阴道镜为筛查方法,活检组织病理学诊断为最终诊断标准,评价机会性筛查用于宫颈癌早诊、早治的意义。结果:4485例患者中一半以上患者不了解宫颈癌相关知识;患者筛查顺应性为98.79%(4431/4485),检出细胞学阳性569例,阳性检出率12.68%(569/4485);561例行高危HPV检测,感染率36.54%(205/561);549例行阴道镜+活检,活检病理结果为:CINⅠ62例,CINⅡ-Ⅲ46例、SCC 8例。2008年宫颈癌筛查参与率及宫颈病变检出率与2007年同期比较差异有统计学意义(P0.05)。结论:通过机会性筛查相关干预措施有助于提高患者对宫颈癌的认知程度,是全面防治宫颈癌的重要内容;机会性筛查顺应性好,能够早期发现宫颈病变,是行之有效的宫颈癌筛查方法,值得推广应用。     

Innovative Approaches to Cervical Cancer Screening for Sex Trade Workers: An International Scoping Review

ObjectiveFemale sex trade workers are among those at highest risk for developing and dying of cervical cancer, and yet many—particularly the most marginalized—are less likely than other women to be screened.This review summarizes global findings on innovative approaches to cervical cancer screening for female sex trade workers, highlights current gaps in the delivery of cervical cancer screening for female sex trade workers globally, and suggests areas for future research and policy development.Data SourcesA scoping review of peer-reviewed publications and grey literature was conducted. Medline (OVID), PubMed, EMBASE, and SCOPUS were searched for relevant studies written in English. There were no limitations placed on dates. Grey literature was identified by hand searching and through discussion with health care providers and community outreach workers currently working with sex trade workers.Study SelectionTwenty-five articles were deemed suitable for review. Articles detailing innovative ways for female sex trade workers to access cervical cancer screening were included. Articles about screening for sexually transmitted infections were also included if the findings could be generalized to screening for cervical cancer. Articles limited to exploring risk factors, knowledge, awareness, education, prevalence, and incidence of cervical cancer among sex trade workers were excluded from the review.Data Extraction and SynthesisSuccessful screening initiatives identified in the studies reviewed had unconventional hours of operation, understood the difference between street-based and venue-based sex trade workers, and/or used peers for outreach.ConclusionTwo significant gaps in health care service delivery were highlighted in this review: the limited use of unorthodox hours and the nearly exclusive practice of providing sexually transmitted infection screening for female sex trade workers without cervical cancer screening. In addition, although street-based (as opposed to venue-based) sex trade workers are likely at higher risk for developing cervical cancer, they are much less likely than other eligible women to participate in screening programs, meaning traditional outreach methods are unlikely to be successful.     

The Role of the Gynaecologist in the UK Cervical Screening Programme

Opportunistic cervical cancer screening began in the United Kingdom in a fragmented manner in the 1960s. Recognizing the failure of this approach to reduce the morbidity and mortality from this preventable cancer, a more structured approach, the National Health Service Cervical Screening Programme, has been in place since 1988. Guidelines for practice and programme management have been developed with the collaboration of the Royal Colleges and those involved in programme delivery. The implementation of quality assurance guidelines for the programme and standards for quality colposcopy services has allowed measurement of me effect of the programme; audits have shewn acceptance of the guidelines. Changes in mortality that had not occurred prior to the implementation of this coordinated programme are beginning to show that the Health of the Nation Target of reducing the incidence of invasive cancer of the cervix by 20 percent by the year 2000 compared to the 1986 rate can be achieved.     

Cervical cancer screening: which HPV test should be used—L1 or E6/E7?

Cervical cancer can and should be a historical disease. The reality, however, is that every year more than half a million women are diagnosed with cervical cancer and a quarter of a million die of this disease. The causal factor for cervical cancer is a persistent HPV infection and therefore a vaccine was developed: prophylactic HPV vaccination will reduce cervical cancer by 70%. Screening based on cytology will miss more than 40% of the abnormalities. The introduction of vaccination should lead to the reintroduction of cervical cancer screening based on HPV detection. Primary HPV screening followed by cytology will detect almost all abnormalities. Not all HPV tests, however, are the same! Clinicians are generally not aware that there is a huge difference among HPV tests. If a low grade lesion progresses to a high grade or invasive cancer, their HPV is likely to integrate. During integration L1 expression can be lost, but E6/E7 expression will always remain present. If the viral HPV is completely integrated then a L1 test looking for only L1 expression will miss this (pre)cancer, while the E6/E7 test will not miss it. HPV tests used in cervical cancer screening should be based on the early (E) and the late (L) genes in order not to miss the abnormality.     

妊娠合并宫颈癌的治疗策略

妊娠合并宫颈癌的治疗策略包括妊娠期宫颈癌的筛查,以及确诊后妊娠期宫颈癌的处理原则。对于妊娠合并宫颈低级别病变可以延迟到产后随访;对于妊娠合并宫颈高级别病变,在除外浸润癌后,可以在妊娠期间定期随访,并延至在产后复查。对已确诊的妊娠合并宫颈癌,在征得患者及家属的知情同意后,可以采取不保留胎儿或继续妊娠的治疗。由于妊娠合并宫颈癌多为个案报道,需要积累更多的前瞻性资料进行研究。     

Cervical screening strategies in resourced and resource-constrained countries

Screening for cervical cancer is well established in resourced countries, but in resource-constrained countries, it is almost non-existent at national level. In resourced countries, the Pap test forms the hallmark of screening, with the human papillomavirus DNA test a recent adjunct. In many resourced countries, however, screening for cervical cancer is still far from ideal. A coverage around 50% prevails in some countries, and few have reached the target of 80% or more. Furthermore, the human papillomavirus test and newly developed biomarkers may lead to the development of a 'super test', which could be applied less frequently compared with present-day cytological screening. In resource-constrained countries, the movement is towards a 'screen and treat' approach. The main screening methods under investigation are the visual inspection after diluted acetic acid application test and the human papillomavirus test. Cryotherapy and large loop excision of the transformation zone have been used most often as treatment methods. The ideal seems to be the human papillomavirus test with large loop excision of the transformation zone, provided a low-cost human papillomavirus test becomes available. Coverage is even a greater problem in resource-constrained countries, a problem in need of urgent attention. Resource-constrained countries, however, must curtail the high incidence of cervical cancer, which is often a lower priority than other pressing healthcare needs.