Cost-effectiveness of alternative triage strategies for atypical squamous cells of undetermined significance

CONTEXT: Every year approximately 2 million US women are diagnosed as having a cervical cytological result of atypical squamous cells of undetermined significance (ASC-US). OBJECTIVE: To determine the most efficient and cost-effective management strategy for women in the United States diagnosed as having ASC-US. DESIGN AND SETTING: Cost-effectiveness analysis of data from clinical trials, prospective studies, and other published literature. A computer-based model was used to compare 4 management strategies for a cytological result of ASC-US: immediate colposcopy; human papillomavirus (HPV) triage, which includes colposcopy if high-risk HPV types are detected; repeat cytology, which includes follow-up cytology at 6 and 12 months and referral for colposcopy if a repeat abnormal result occurs; and reclassifying ASC-US as normal in which a cytological result of ASC-US is ignored. Reflex HPV DNA testing uses either residual liquid-based cytological specimens or samples co-collected at the time of the initial screening for conventional cytology. Another method, referred to as the 2-visit HPV DNA triage, requires a woman with an ASC-US result to return within 1 month to provide another speciman sample. MAIN OUTCOME MEASURES: Years of life saved (YLS), quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios. RESULTS: The least costly strategy for biennial screening was to reclassify ASC-US as normal, resulting in a reduction in total cancer incidence of 75% for conventional cytology and 84% for liquid-based cytology compared with no screening. The next least costly strategy was HPV DNA testing resulting in a reduction in total cancer incidence of 86% for conventional cytology and 90% for liquid-based cytology, followed by immediate colposcopy with a reduction of 87% and 91%, respectively. Compared with reflex HPV DNA testing, a strategy of repeat cervical cytology or delayed HPV testing costs more but is less effective. When all strategies were compared simultaneously, varying frequency and type of cytological test, biennial (vs every 3 years) liquid-based cytology with reflex HPV testing had a cost of $174 200 per YLS. In a similar comparison, liquid-based cytology with reflex HPV testing conducted every 3 years (vs every 5 years) had a cost of $59 600 per YLS and was more effective and less costly than a strategy of conventional cytology incorporating repeat cytology or immediate colposcopy conducted biennially. CONCLUSION: Reflex HPV DNA testing provides the same or greater life expectancy benefits and is more cost-effective than other management strategies for women diagnosed as having ASC-US.     

Benefits and costs of using HPV testing to screen for cervical cancer

CONTEXT: Despite quality assurance standards, Papanicolaou (Pap) test characteristics remain less than optimal. OBJECTIVE: To compare the societal costs and benefits of human papillomavirus (HPV) testing, Pap testing, and their combination to screen for cervical cancer. DESIGN, SETTING, AND POPULATION: A simulation model of neoplasia natural history was used to estimate the societal costs and quality-adjusted life expectancy associated with 18 different general population screening strategies: Pap plus HPV testing, Pap testing alone, and HPV testing alone every 2 or 3 years among hypothetical longitudinal cohorts of US women beginning at age 20 years and continuing to 65 years, 75 years, or death. MAIN OUTCOME MEASURE: Discounted costs per quality-adjusted life-year (QALY) saved of each screening strategy. RESULTS: Maximal savings in lives were achieved by screening every 2 years until death with combined HPV and Pap testing at an incremental cost of $76 183 per QALY compared with Pap testing alone every 2 years. Stopping biennial screening with HPV and Pap testing at age 75 years captures 97.8% of the benefits of lifetime screening at a cost of $70 347 per QALY. Combined biennial HPV and Pap testing to age 65 years captures 86.6% of the benefits achievable by continuing to screen until age 75 years. Human papillomavirus screening alone was equally effective as Pap testing alone at any given screening interval or age of screening cessation but was more costly and therefore was dominated. In sensitivity analyses, HPV testing would be more effective and less costly than Pap testing at a cost threshold of $5 for an HPV test. CONCLUSIONS: Screening with HPV plus Pap tests every 2 years appears to save additional years of life at reasonable costs compared with Pap testing alone. Applying age limits to screening is a viable option to maintain benefits while reducing costs.     

Continuing screening mammography in women aged 70 to 79 years: impact on life expectancy and cost-effectiveness

CONTEXT: Mammography is recommended and is cost-effective for women aged 50 to 69 years, but the value of continuing screening mammography after age 69 years is not known. In particular, older women with low bone mineral density (BMD) have a lower risk of breast cancer and may benefit less from continued screening. OBJECTIVE: To compare life expectancy and cost-effectiveness of screening mammography in elderly women based on 3 screening strategies. DESIGN: Decision analysis and cost-effectiveness analysis using a Markov model. PATIENTS: General population of women aged 65 years or older. INTERVENTIONS: The analysis compared 3 strategies: (1) Undergoing biennial mammography from age 65 to 69 years; (2) undergoing biennial mammography from age 65 to 69 years, measurement of distal radial BMD at age 65 years, discontinuing screening at age 69 years in women in the lowest BMD quartile for age, and continuing biennial mammography to age 79 years in those in the top 3 quartiles of distal radius BMD; and (3) undergoing biennial mammography from age 65 to 79 years. MAIN OUTCOME MEASURES: Deaths due to breast cancer averted, life expectancy, and incremental cost-effectiveness ratios. RESULTS: Compared with discontinuing mammography screening at age 69 years, measuring BMD at age 65 years in 10000 women and continuing mammography to age 79 years only in women with BMD in the top 3 quartiles would prevent 9.4 deaths and add, on average, 2.1 days to life expectancy at an incremental cost of $66773 per year of life saved. Continuing mammography to age 79 years in all 10000 elderly women would prevent 1.4 additional breast cancer deaths and add only 7.2 hours to life expectancy at an incremental cost of $117689 per year of life saved compared with only continuing mammography to age 79 years in women with BMD in the top 3 quartiles. CONCLUSIONS: This analysis suggests that continuing mammography screening after age 69 years results in a small gain in life expectancy and is moderately cost-effective in those with high BMD and more costly in those with low BMD. Women's preferences for a small gain in life expectancy and the potential harms of screening mammography should play an important role when elderly women are deciding about screening.     

Cost-effectiveness of screening for colorectal cancer in the general population

CONTEXT: A recent expert panel recommended that persons at average risk of colorectal cancer (CRC) begin screening for CRC at age 50 years using 1 of several strategies. However, many aspects of different CRC screening strategies remain uncertain. OBJECTIVE: To assess the consequences, costs, and cost-effectiveness of CRC screening in average-risk individuals. DESIGN: Cost-effectiveness analysis from a societal perspective using a Markov model. SUBJECTS: Hypothetical subjects representative of the 50-year-old US population at average risk for CRC. SETTING: Simulated clinical practice in the United States. MAIN OUTCOME MEASURES: Discounted lifetime costs, life expectancy, and incremental cost-effectiveness (CE) ratio, compared used 22 different CRC screening strategies, including those recommended by the expert panel. RESULTS: In 1 base-case analysis, compliance was assumed to be 60% with the initial screen and 80% with follow-up or surveillance colonoscopy. The most effective strategy for white men was annual rehydrated fecal occult blood testing (FOBT) plus sigmoidoscopy (followed by colonoscopy if either a low- or high-risk polyp was found) every 5 years from age 50 to 85 years, which resulted in a 60% reduction in cancer incidence and an 80% reduction in CRC mortality compared with no screening, and an incremental CE ratio of $92,900 per year of life gained compared with annual unrehydrated FOBT plus sigmoidoscopy every 5 years. In a base-case analysis in which compliance with screening and follow-up is assumed to be 100%, screening more often than every 10 years was prohibitively expensive; annual rehydrated FOBT plus sigmoidoscopy every 5 years had an incremental CE ratio of $489,900 per life-year gained compared with the same strategy every 10 years. Other strategies recommended by the expert panel were either less effective or cost more per year of life gained than the alternatives. Colonoscopy every 10 years was less effective than the combination of annual FOBT plus sigmoidoscopy every 5 years. However, a single colonoscopy at age 55 years achieves nearly half of the reduction in CRC mortality obtainable with colonoscopy every 10 years. Because of increased life expectancy among white women and increased cancer mortality among blacks, CRC screening was even more cost-effective in these groups than in white men. CONCLUSIONS: Screening for CRC, even in the setting of imperfect compliance, significantly reduces CRC mortality at costs comparable to other cancer screening procedures. However, compliance rates significantly affect the incremental CE ratios. In this model of CRC, 60% compliance with an every 5-year schedule of screening was roughly equivalent to 100% compliance with an every 10-year schedule. Mathematical modeling used to inform clinical guidelines needs to take into account expected compliance rates. JAMA. 2000;284:1954-1961.     

The clinical effectiveness and cost-effectiveness of screening for anal squamous intraepithelial lesions in homosexual and bisexual HIV-positive men.

CONTEXT: Homosexual and bisexual men infected with human immunodeficiency virus (HIV) are at increased risk for human papillomavirus-related anal neoplasia and anal squamous cell carcinoma (SCC). OBJECTIVE: To estimate the clinical benefits and cost-effectiveness of screening HIV-positive homosexual and bisexual men foranal squamous intraepithelial lesions (ASIL) and anal SCC. DESIGN: Cost-effectiveness analysis performed from a societal perspective that used reference case recommendations from the Panel on Cost-Effectiveness in Health and Medicine. A state-transition Markov model was developed to calculate lifetime costs, life expectancy, and quality-adjusted life expectancy for no screening vs several screening strategies for ASIL and anal SCC using anal Papanicolaou (Pap) testing at different intervals. Values for incidence, progression, and regression of anal neoplasia; efficacy of screening and treatment; natural history of HIV; health-related quality of life; and costs were obtained from the literature. SETTING AND PARTICIPANTS: Hypothetical cohort of homosexual and bisexual HIV-positive men living in the United States. MAIN OUTCOME MEASURES: Life expectancy, quality-adjusted life expectancy, quality-adjusted years of life saved, lifetime costs, and incremental cost-effectiveness ratio. RESULTS: Screening for ASIL increased quality-adjusted life expectancy at all stages of HIV disease. Screening with anal Pap tests every 2 years, beginning in early HIV disease (CD4 cell count >0.50 x 10(9)/L), resulted in a 2.7-month gain in quality-adjusted life expectancy for an incremental cost-effectiveness ratio of $13,000 per quality-adjusted life year saved. Screening with anal Pap tests yearly provided additional benefit at an incremental cost of $16,600 per quality-adjusted life year saved. If screening was not initiated until later in the course of HIV disease (CD4 cell count <0.50 x 10(9)/L), then yearly Pap test screening was preferred due to the greater amount of prevalent anal disease (cost-effectiveness ratio of less than $25,000 per quality-adjusted life year saved compared with no screening). Screening every 6 months provided little additional benefit over that of yearly screening. Results were most sensitive to the rate of progression of ASIL to anal SCC and the effectiveness of treatment of precancerous lesions. CONCLUSIONS: Screening HIV-positive homosexual and bisexual men for ASIL and anal SCC with anal Pap tests offers quality-adjusted life expectancy benefits at a cost comparable with other accepted clinical preventive interventions.     

Human papillomavirus distribution and cervical cancer epidemiological characteristics in rural population of Xinjiang,China

Background:Cervical cancer remains a major public health issue for the Uyghur women and other women living mainly in rural areas of Xinjiang. This study aims to investigate the distribution of human papillomavirus (HPV) infection and cervical cancer in rural areas of Xinjiang, China.Methods:Cervical cancer screening was performed on rural women aged 35 to 64 years from Xinjiang, China in 2017 through gynecological examination, vaginal discharge smear microscopy, cytology, and HPV testing. If necessary, colposcopy and biopsy were performed on women with suspicious or abnormal screening results.Results:Of the 216,754 women screened, 15,518 received HPV testing. The HPV-positive rate was 6.75% (1047/15,518). Compared with the age 35–44 years group, the odds ratios (ORs) of HPV positivity in the age 45–54 years and 55–64 years groups were 1.18 (95% confidence interval [CI]: 1.02–1.37) and 1.84 (95% CI: 1.53–2.21), respectively. Compared with women with primary or lower education level, the ORs for HPV infection rates of women with high school and college education or above were 1.37 (95% CI: 1.09–1.72) and 1.62 (95% CI: 1.23–2.12), respectively. Uyghur women were less likely to have HPV infection than Han women, with an OR (95% CI) of 0.78 (0.61–0.99). The most prevalent HPV types among Xinjiang women were HPV 16 (24.00%), HPV 33 (12.70%), and HPV 52 (11.80%). The detection rate of cervical intraepithelial neoplasia (CIN)2+ was 0.14% and the early diagnosis rate of cervical cancer was 85.91%. The detection rates of vaginitis and cervicitis were 19.28% and 21.32%, respectively.Conclusions:The HPV infection rate in Xinjiang is low, but the detection rate of cervical cancer and precancerous lesions is higher than the national average level. Cervical cancer is a prominent public health problem in Xinjiang, especially in southern Xinjiang.     

Role of VIA in cervical cancer screening in low-resource countries

Cervical cancer is one of the few highly preventable cancers. The early detection and removal of precancerous cervical lesions effectively abolish the development of invasive cervical cancer. The Pap test has been the standard screening test in the Western world for the last five decades. Visual inspection of cervix with acetic acid (VIA) is currently more popular method of cervical cancer of screening test in low resource countries. Cervical cancer incidence and mortality have been reduced dramatically as a result of successful screening in many countries. Cancer cervix can be prevented through both primary prevention using human papilloma virus (HPV) vaccine and early detection using screening techniques. Several screening modalities are now available for early detection of cervical cancer and its precursor lesions. They all differ with regard to their test characteristics, feasibility and economic considerations. This review has different aspects of these screening modalities and provides different options considering mass application. In developed countries, Pap smear cytology is used for cervical cancer screening. But in low-resource country, like Bangladesh, it is too expensive and is not feasible. VIA, a non-cytological test is a simple and inexpensive test which can be provided by trained paramedical personnel with a short training. So VIA can be done in low-resource countries for screening of cervical cancer as an alternative to Pap smear cytology.     

Comparing the results of Pap smear and Direct Visual Inspection (DVI) with 5% acetic acid in cervical cancer screening

Background:

Cervical cancer is the most second common cancer among Iranian women. This study was carried out to compare the results of Pap smear method and Direct Visual Inspection (DVI) with 5% acetic acid in cervical cancer screening in Tabriz, Iran.

Material and Methods:

This cross-sectional study was carried out in Alzahra Therapeutic-Educational Centre, Tabriz, Iran in 2013 on 1000 women. First, Pap smear was done for all women, and then the cervix exposed with 5% acetic acid by cotton swab for 30 seconds and observed under adequate light. At the end, women with abnormal results in Pap smear or DVI method were referred to colposcopy and biopsy. Test''s sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV), LR+, LR- and confidence interval (CI) were determined (P < 0.05).

Results:

Nine-hundred and seventy-four (94.7%) cases were normal and had no abnormal findings and 26 (2.6%) participants had positive results in Pap smear or DVI test. Twelve women had abnormal Pap smear (nine women with atypical squamous cells of undetermined significance, ASCUS, three women with dysplasia, atypical endocervical, and low-grade squamous intraepithelial lesion, LSIL results) and 14 women had positive DVI (four women with human papillomavirus, HPV or koilocyte,) and one women with abnormality in both method had carcinoma in biopsy that referred to oncologist. In this study the sensitivity, specificity, PPV and NPV for DVI were 71.4%, 50%, 35.7%, and 81.8% respectively in comparison with 14.3%, 50%, 10%, and 60% for Pap smear.

Conclusion:

As the DVI method has higher sensitivity and positive predictive value than Pap smear, it could be used as a useful method beside the Pap smear.     

Human papillomavirus research on the prevention, diagnosis, and prognosis of cervical cancer in Taiwan

Cervical cancer is third in incidence and fourth in mortality among cancers of women worldwide. Epidemiological studies have shown that human papillomavirus (HPV) is necessary, if not sufficient, to cause nearly 100% of cervical cancers. HPV testing is useful in primary screening for cervical neoplasms. The value of HPV detection or genotyping is potentially useful in triage of borderline or low-grade abnormal cervical cytology, follow-up after treatment of cervical intraepithelial neoplasia, assessment of prognosis and treatment planning for invasive cervical cancer. Studies from Chang Gung Memorial Hospital have defined the genotype distribution of cervical cancer in Taiwan and confirmed the independent prognostic value of the HPV genotype in cervical cancer. The cost-effectiveness of using HPV testing in prevention and management of cervical neoplasms depends on the medical and public health infrastructure of the individual country. The population-based HPV prevalence and genotype distribution as well as longitudinal follow-up studies have established strong support for incorporating HPV testing with cervical cytology and for future comparisons of HPV epidemiology before and after implementation of HPV prophylactic vaccines in Taiwan. Future directions in HPV research are discussed.     

Human papillomavirus screening and cervical cancer prevention

Infection with one of several types of human papillomavirus (HPV) appears to be a necessary first step in the development of invasive cervical cancer. We cannot currently treat HPV infections; thus, the role of HPV testing is to identify women with precancerous lesions that can be removed and, in so doing, prevent progression to invasive carcinoma. Although HPV testing may help to identify women at risk of cervical cancer who might be missed by other screening tests, it is inherently nonspecific at identifying those who would otherwise develop cervical cancer. In order to avoid overtreatment of women with minor lesions with little potential for progression, HPV testing needs to be repeated or combined with Pap smears. Protocols for HPV screening have yet to be properly evaluated. Here we consider several possible applications of HPV testing in the prevention of cervical cancer. The most immediate role is as a secondary test in women with minor cytological abnormalities. Appropriate use of HPV testing as a primary screening tool depends on the setting. In a developed country without an organized screening program, HPV testing might be used in addition to Pap smears in women age 35 and over to increase sensitivity. Within an organized screening program, HPV testing might be used in combination with Pap testing, but with extended screening intervals so as to obtain the maximum advantage to women without unduly increasing costs. Where resources are strictly limited, an attractive option would be to perform visual inspection of the cervix after application of dilute acetic acid using a low threshold for referral, and to test for HPV only on those with abnormal looking lesions.     

Potential health and economic impact of adding a human papillomavirus vaccine to screening programs

Context  Recently published results suggest that effective vaccines against cervical cancer—associated human papillomavirus (HPV) may become available within the next decade. Objective  To examine the potential health and economic effects of an HPV vaccine in a setting of existing screening. Design, Setting, and Population  A Markov model was used to estimate the lifetime (age 12-85 years) costs and life expectancy of a hypothetical cohort of women screened for cervical cancer in the United States. Three strategies were compared: (1) vaccination only; (2) conventional cytological screening only; and (3) vaccination followed by screening. Two of the strategies incorporated a vaccine targeted against a defined proportion of high-risk (oncogenic) HPV types. Screening intervals of 1, 2, 3, and 5 years and starting ages for screening of 18, 22, 24, 26, and 30 years were chosen for 2 of the strategies (conventional cytological screening only and vaccination followed by screening). Main Outcome Measures  Incremental cost per life-year gained. Results  Vaccination only or adding vaccination to screening conducted every 3 and 5 years was not cost-effective. However, at more frequent screening intervals, strategies combining vaccination and screening were preferred. Vaccination plus biennial screening delayed until age 24 years had the most attractive cost-effectiveness ratio ($44 889) compared with screening only beginning at age 18 years and conducted every 3 years. However, the strategy of vaccination with annual screening beginning at age 18 years had the largest overall reduction in cancer incidence and mortality at a cost of $236 250 per life-year gained compared with vaccination and annual screening beginning at age 22 years. The cost-effectiveness of vaccination plus delayed screening was highly sensitive to age of vaccination, duration of vaccine efficacy, and cost of vaccination. Conclusions  Vaccination for HPV in combination with screening can be a cost-effective health intervention, but it depends on maintaining effectiveness during the ages of peak oncogenic HPV incidence. Identifying the optimal age for vaccination should be a top research priority.      

Cost-effectiveness of low-molecular-weight heparin and unfractionated heparin in treatment of deep vein thrombosis

BACKGROUND: Acute deep vein thrombosis has traditionally been treated with unfractionated heparin (UFH), administered intravenously, but low-molecular-weight heparins (LMWH), administered subcutaneously, have recently become available. The authors sought to determine which therapy was more cost-effective for inpatient and outpatient treatment of deep vein thrombosis. METHODS: An incremental cost-effectiveness analysis based on a decision tree was performed for 4 treatment strategies for deep vein thrombosis. Rate of major hemorrhage while receiving heparin, rate of recurrence of venous thromboembolism 3 months after treatment and mortality rate 3 months after treatment were determined by meta-analysis. Costs for the UFH therapy were prospectively collected by a case-costing accounting system for 105 patients with deep vein thrombosis treated in fiscal year 1995/96. The costs for LMWH therapy were modelled, and cost-effectiveness was determined by decision analysis. RESULTS: Meta-analysis revealed a mean difference in risk of hemorrhage of -1.1% (95% confidence interval [CI] -2.4% to 0.3%), a mean difference in risk of recurrence of venous thromboembolism of -2.6% (95% CI -4.5% to -0.7%) and a mean difference in risk of death of -1.9% (95% CI -3.6% to -0.4%), all in favour of subcutaneous unmonitored administration of LMWH. The cost to treat one inpatient was $2993 for LMWH and $3048 for UFH. Even more would be saved if LMWH was delivered on an outpatient basis (cost of $1641 per patient). The cost-effectiveness analysis showed that LMWH in any treatment setting is more cost effective than UFH. A sensitivity analysis demonstrated the robustness of this conclusion. INTERPRETATION: Treatment of deep vein thrombosis with LMWH is more cost effective than treatment with UFH in both inpatient and outpatient settings.     

Is Routine Human Papillomavirus Vaccination an Option for Ghana?

Cervical cancer remains an important public health problem in developing countries where over 80% of the global burden occurs annually but screening has been ineffective. In a polygamous country like Ghana with a high incidence of cervical cancer but no national screening program, the Human Papilloma Virus (HPV) vaccine presents a unique opportunity to reduce the burden of HPV infection and cervical cancer in Ghanaian women. The evidence so far indicates that the vaccines are safe and efficacious. Although routine HPV vaccination of girls raises several religious, political, socioeconomic and ethical challenges, the emphasis of this paper will be on addressing the ethical challenges using the principles of autonomy, beneficence, non-maleficence and justice as a framework. Parental autonomy can be preserved with judicious exemptions for those who decline the vaccine on religious and philosophical grounds. This promotes public health without trampling parental authority. Routine HPV vaccination confers several benefits to individuals and society by preventing HPV infection. Instead of causing harm; it reduces harm by preventing the development of about 70% of cervical cancers and removing the negative physical and psychological impact of a cervical cancer diagnosis. It also has the potential to reduce the disparities in cervical cancer rates and its cost effectiveness will ensure considerable cost savings in terms of the money spent on diagnosis and treatment. Consequently, the HPV vaccine is an important public health landmark and achievement in women's health that must be heralded, especially in developing countries where the bulk of the disease and death occur.     

Periodic health examination, 1995 update: 1. Screening for human papillomavirus infection in asymptomatic women. Canadian Task Force on the Periodic Health Examination.

OBJECTIVE: To develop recommendations for practising physicians on the advisability of screening for human papillomavirus (HPV) infection in asymptomatic women. OPTIONS: Visual inspection, Papanicolaou testing, colposcopy or cervicography, use of HPV group-specific antigen, DNA hybridization, dot blot technique, Southern blot technique or polymerase chain reaction followed by physical or chemical therapeutic intervention. OUTCOMES: Evidence for a link between HPV infection and cervical cancer, sensitivity and specificity of HPV screening techniques, effectiveness of treatments for HPV infection, and the social and economic costs incurred by screening. EVIDENCE: MEDLINE was searched for articles published between January 1966 to June 1993 with the use of the key words "papillomavirus," "cervix neoplasms," "mass screening," "prospective studies," "prevalence," "sensitivity," "specificity," "human" and "female." VALUES: Proven cost-effective screening techniques that could lead to decreased morbidity or mortality were given a high value. The evidence-based methods and values of the Canadian Task Force on the Periodic Health Examination were used. BENEFITS, HARMS AND COSTS: Potential benefits are to prevent cervical cancer and eliminate HPV infection. Potential harmful effects include the creation of an unnecessary burden on the health care system and the labelling of otherwise healthy people as patients with a sexually transmitted disease for which therapy is generally ineffective. Potential costs would include expense of testing, increased use of colposcopy and treatment. RECOMMENDATIONS: There is fair evidence to exclude HPV screening (beyond Papanicolaou testing for cervical cancer) in asymptomatic women (grade D recommendation). VALIDATION: The report was reviewed by members of the task force and three external reviewers who were selected to represent different areas of expertise. SPONSORS: These guidelines were developed and endorsed by the task force, which is funded by Health Canada and the National Health Research and Development Program. The principal author (K.J.) was supported in part by the National Health Research and Development Program through a National Health Fellowship (AIDS).     

宫颈癌扩大筛检计划的成本效益分析

目的：探讨扩大宫颈癌筛检覆盖率计划是否具有成本效益。方法：利用浏阳市11年来的宫颈癌普查资料和浏阳市公共卫生综合试点调查资料,对现行的宫颈癌筛检和扩大筛检覆盖率的方案进行比较和成本效益分析。结果：采取扩大筛检计划后,浏阳市30~59岁已婚妇女的筛检覆盖率从7.20%上升至66.67%（u=17.84, P＜0.001）,每周期早期发现病例从20例增加到45例,避免减寿命年数从103.46增加至925.83个生命年。成本效益分析提示：多挽救1个寿命年平均需花费6 917.07元。从筛检的成本效益比来看,筛检覆盖率为66.67%时的效益成本比为1.80∶1,高于常规筛检的效益成本比1.40∶1,且两种方案均有较好的成本效益。 结论：通过强化宣传,提前通知等方式,提高宫颈癌筛检的覆盖率,具有较好的成本效益。     

Cervical cancer: epidemiology, prevention and the role of human papillomavirus infection

ORGANIZED SCREENING HAS CONTRIBUTED TO A DECLINE in cervical cancer incidence and mortality over the past 50 years. However, women in developing countries are yet to profit extensively from the benefits of screening programs, and recent trends show a resurgence of the disease in developed countries. The past 2 decades have witnessed substantial progress in our understanding of the natural history of cervical cancer and in major treatment advances. Human papillomavirus (HPV) infection is now recognized as the main cause of cervical cancer, the role of coexisting factors is better understood, a new cytology reporting terminology has improved diagnosis and management of precursor lesions, and specific treatment protocols have increased survival among patients with early or advanced disease. Current research has focused on the determinants of infection with oncogenic HPV types, the assessment of prophylactic and therapeutic vaccines and the development of screening strategies incorporating HPV testing and other methods as adjunct to cytology. These are fundamental stepping stones for the implementation of effective public health programs aimed at the control of cervical cancer.     

绝经后宫颈癌发病情况分析

目的探讨绝经后宫颈癌发病特征及宫颈癌筛查的必要性。方法回顾性分析40例绝经后宫颈癌患者临床资料,并以同期育龄宫颈癌患者40例作为对照,比较两组临床表现及病理学特征。结果绝经组接触性出血发生率为22．50％（9／40）,明显低于育龄组（60．00％,24／40）;绝经组盆腔淋巴结转移、宫颈深肌层浸润／脉管瘤栓发生例数明显高于育龄组,差异有高度统计学意义（P〈0．01）;TCT细胞学检查及HPV检测阳性率两组比较差异无统计学差异（P〉0．05）。结论绝经后宫颈癌无典型症状和体征,中晚期浸润癌发生率高,绝经后宫颈癌筛查是必要的。     

Current and projected annual direct costs of screening asymptomatic men for prostate cancer using prostate-specific antigen

BACKGROUND: Concern over the cost of screening for asymptomatic prostate cancer by means of prostate-specific antigen (PSA) testing has played an important role in PSA screening policy. However, little is known about the true costs of current PSA screening in Canada and how costs may change in the future. METHODS: The authors performed a cost identification study from the perspective of provincial ministries of health. They used data from published reports, hospital discharge data, claims data from several provinces, a laboratory survey, a national survey of knowledge, attitudes and beliefs about screening, a provincial cancer registry and expert opinion to estimate current first-year screening costs. Using demographic data from Statistics Canada and various scenarios regarding changes in screening patterns, the authors derived estimates of the future costs of PSA screening. RESULTS: In 1995 PSA screening cost an estimated $45 million (range $40 million to $84 million). Treatment accounted for over 61% of total costs, whereas screening, diagnosis and staging accounted for 35%. Screening all eligible men in Canada in 1995 would have cost $317 million (range $356 million to $691 million), more than the costs of all prostate cancer care in that year. Annual recurrent screening for all eligible men in 2005 would cost $219 million (range $208 million to $412 million). Projections from existing trends suggest that annual costs of PSA screening in 2000 are likely to increase from the estimated $45 million to approximately $66 million (range $59 million to $126 million). INTERPRETATION: PSA screening is costly, but even universal screening would consume a smaller share of national health expenditures than previous studies have suggested. Costs attributable to PSA screening may increase in the future owing to changes in utilization patterns and demographic shifts.     

高危型人乳头瘤病毒检测在子宫颈病变筛查和处理中的意义及作用

人乳头瘤病毒(HPV)感染是子宫颈癌发生的必要因素,HPV检测可最大程度优化子宫颈筛查和子宫颈异常细胞学的临床处理。对于30岁以上妇女,如HPV检测为阴性且子宫颈细胞学检查正常,可安全地将子宫颈筛查间隔延长至3年。但是,由于HPV病毒感染在年轻妇女中常见且多为一过性感染,因此不建议将HPV检测作为年龄小于30岁妇女的子宫颈筛查内容。对于任何年龄妇女,建议将HPV检测作为未明确诊断的不典型鳞状上皮细胞患者的分流检测方法,同时对于不能除外高度鳞状上皮内病变的不典型鳞状上皮细胞、鳞状上皮内低度病变或不典型腺细胞而未发现中或重度不典型增生的患者,HPV也是随诊方法之一。对于治疗后患者,HPV检测也和阴道镜及子宫颈细胞学一样,可作为随诊方法。HPV检测的正确使用可促进异常子宫颈细胞学的处理。     

薄层液基细胞学与人乳头瘤病毒联合检测在宫颈上皮病变筛查中的应用

目的探讨薄层液基细胞学（TCT）与人乳头瘤病毒（HPV）联合检测在宫颈上皮病变筛查中的应用。方法对在我院妇科门诊就诊和体检进行TCT联合HPV检测的妇女,选择单纯TCT阳性者121例为TCT组,单纯HPV阳性者169例为HPV组,两者均阳性者92例为TCT联合HPV组,三组均经阴道镜下取活检,以组织病理学为金标准,比较三组与组织病理学诊断的阳性预测值。分析TCT联合HPV检测双阳性与TCT和HPV单纯阳性在宫颈上皮病变筛查效果中有无差异。结果TCT组、HPV组、TCT联合HPV组与组织病理学诊断的阳性预测值分别为57．02％、30．77％、75．00％。TCT联合HPV组与TCT组比较差异有统计学意义（Х^2=7．40,P〈0．05）,TCT联合HPV组与HPV组比较差异有统计学意义（Х^2=46．87,P〈0．05）。结论TCT联合HPV检测筛查宫颈上皮病变明显优于TCT和HPV的单纯检测,是宫颈癌及癌前病变筛查较理想的方法。