Efficacy of screening for cervical cancer: a review.

Cytologic screening for cervical cancer currently enjoys wide acceptance, but there remains controversy in the literature concerning its efficacy in prolonging life. On the basis of a literature review, several conclusions are reached: 1) Cervical screening can identify women who are at greater-than-average risk of developing invasive cervical cancer by detecting asymptomatic lesions that would frequently progress to invasion if left untreated; 2) Therapy based on confirmed positive smears can reduce the incidence and mortality rates of invasive cervical cancer, as shown by declining rates in many centers that had constant or increasing rates before screening began, lower rates for geographic areas and occupational groups having less screening, and lower rates among screened women than unscreened women; and 3) Attempts to estimate the amount of life prolongation attributable to cervical screening have not yet yielded reliable figures, because of difficulties with the models or data used. However, in view of the available evidence, it is suggested that incomplete data should not prevent a vigorous continuation of screening where it is already extensive, and an escalation where it is not.     

Invasive cervical cancer among American Indian women in the Northern Plains, 1994-1998: incidence, mortality, and missed opportunities

OBJECTIVES: Cervical cancer mortality rates among the American Indian and Alaska Native (AI/AN) population in North and South Dakota were five times the national average (15.6 per 100,000 vs. 3.1 per 100,000, age adjusted) when last evaluated (from 1989 through 1993). Our goals were to update the AI/AN population cervical cancer mortality rates and to present incidence rates for AI/AN women in the region. METHODS: We reviewed charts for women diagnosed with invasive cervical cancer at Indian Health Service (IHS) facilities in North and South Dakota from 1994 through 1998 and collected information about cervical cancer screening and treatment history. Incidence and mortality rates were standardized to the 1970 U.S. population. RESULTS: Twenty-one cases of invasive cervical cancer and eight deaths were identified. Annualized incidence and mortality rates were 11.5 per 100,000 and 4.5 per 100,000. These compare with national all-race/ethnicity rates of 8.5 per 100,000 and 2.7 per 100,000 for incidence and mortality. Fifteen (71%) of 21 cases were diagnosed due to symptoms. CONCLUSIONS: While cervical cancer mortality rates have declined, incidence and mortality rates among AI/AN women remain higher than in the general U.S. population. Increased use of pap tests and careful follow-up of abnormal results should be aggressively promoted among AI/AN women in North and South Dakota.     

Breast cancer trends among young women in the United States

BACKGROUND: It has been suggested that exposures associated with industrialization have increased breast cancer risk among young women in recent decades in the United States despite data demonstrating declining breast cancer mortality in birth cohorts born after 1945. METHODS: Trends for in situ and invasive breast cancer incidence rates from 1975 through 2002 among white and black U.S. women ages 20 to 49 are evaluated by decade of age using linear regression analyses. RESULTS: Despite increasing rates of in situ breast cancer after 1980 reflecting increased use of mammography, invasive breast cancer rates declined for both white and black women under age 50. These declines are consistent with a decrease in birth cohort risk of breast cancer for women born after 1945. CONCLUSIONS: Invasive breast cancer incidence rates are not increasing in young U.S. women despite increases in mammography and trends in known risk factors (eg, reproductive factors) that would predict increasing risk.     

Breast and cervical cancer surveillance, United States, 1973-1987.

Breast and cervical cancer incidence and mortality rates were reviewed for the period 1973-1987. For breast cancer, mortality has been relatively stable, increasing from 26.9/100,000 women in 1973 to 27.1 in 1987. Alternatively, data from the National Cancer Institute's Surveillance, Epidemiology, End Results Program (SEER) showed a 36% increase in the incidence of this malignancy over the same period. In 1987, overall incidence of invasive breast cancer was 111.9/100,000 women. White women experienced lower overall mortality rates and higher overall incidence than black women; however, these differences varied by age. Examination of breast cancer incidence by stage of disease at diagnosis revealed that rates for distant and regional disease have remained relatively stable since 1973. In contrast, rates of localized and in situ cancers exhibited an increase in the 1980s that may correspond to increased use of mammography in this country. The rate of decline in cervical cancer incidence and mortality has slowed in recent years. In 1987, 3.0 cervical cancer deaths/100,000 women occurred. SEER incidence for invasive disease for that year was 8.2/100,000. Rates varied by race, age, state, and stage of disease. In general, black women experienced much higher incidence and mortality from invasive cervical cancer than white women. For both races, rates of in situ disease were highest among young women and decreased rapidly with age. Rates of in situ cervical cancer were consistently higher than rates of invasive cancer for the time period studied.     

Trends in incidence of and mortality from invasive cancer of the uterine cervix in Scotland (1975–1994)

Objective: I. To identify major trends in the incidence of and mortality from invasive cancer of the cervix uteri in Scotland during the twenty year period 1975–1994; II. to consider the extent to which these trends may have been shaped by the introduction of systematic cervical screening.Design: Analysis of annual age standardised and age specific rates for incidence and mortality, based on data collected by the Scottish Cancer Registry and the General Register Office for Scotland.Setting: Scotland.Subjects: Women registered with the Scottish Cancer Registry as having developed invasive cancer of the cervix during the period of interest.Results: Annual all ages incidence rates of invasive cervical cancer show little overall change over the period 1975–1989, but exhibit a pronounced decline from 1990 onwards. All-ages mortality rates show clear evidence of decline during the period 1975–1994, the rate for 1994 being some 30% lower than that for 1975. Annual age-specific incidence rates show different patterns by age group, with clear evidence of decreasing trends in the age range 50–64 years but different patterns in younger and older age groups. Most age groups show steep declines in incidence from 1990 onwards. Age specific mortality rates for 1975–1994 exhibit the most pronounced decreasing trends in the age range 50–64 years. The trends identified are broadly similar to those experienced in England and Wales over an approximately comparable period.Conclusions: The overall (all ages) incidence of invasive cervical cancer in Scotland changed little during the period 1975–1989, but declined sharply from 1990 onwards. The most pronounced decline in incidence across the period 1975–1994 appears to have taken place in the age range 50–64 years. This decline has been accompanied by a commensurate fall in mortality in the same age range. These reductions in incidence and mortality may be attributable in part to increased coverage of cervical screening programmes during the period of interest. Evidence from other studies suggest that, without the increased coverage of cervical screening achieved during this period incidence rates in Scotland might have been seen to increase.     

Relationships between socioeconomic status and race-specific cervical cancer incidence in the United States, 1973-1992

The association between low socioeconomic status (SES) in minority groups and higher incidence and mortality from cervical cancer was examined using two large U.S. databases. With cases from 1973 to 1992, all registries of the Surveillance, Epidemiology, and End Results (SEER) (except Hawaii) were used to calculate incidence rates of in situ and invasive cervical cancers by race group. SES indicators were derived from the Regional Economic Information System, Department of Commerce. Higher levels of SES indicators were related to decreased risk and lower incidence of invasive cancers in all race groups, but especially white and black populations, and to increased incidence of situ cancer in these populations. Results suggest that higher SES status is related to a decrease in invasive cervical cancer, but an increase in in situ cervical cancer in recent years. These findings may explain the racial differences in cervical cancer incidence and help target intervention programs.     

Esperanza y Vida: a culturally and linguistically customized breast and cervical education program for diverse Latinas at three different United States sites

Breast cancer is the most common cause of cancer and the leading cause of cancer death among Latinas in the United States. In addition, Latinas experience a disproportionate burden of cervical cancer incidence, morbidity, and mortality compared with non-Hispanic White women. Lower use of breast and cervical cancer screening services may contribute to these disparities. To address the underutilization of breast and cervical cancer screening among diverse subgroups of Latinas, a peer-led education program called Esperanza y Vida ("Hope and Life") was developed and administered at 3 sites (2 in New York and 1 in Arkansas). Immigrant Latina women and their partners were educated about the importance of breast and cervical cancer screening, with the goals of increasing their knowledge about these cancers and their screening behavior. An analysis of the intervention's findings at baseline among female participants demonstrated significant sociodemographic, interpersonal, cultural, health care system, and program variability in 3 distinct geographic regions in the United States. These data indicate the need for and feasibility of customizing cancer outreach and educational programs for diverse Latina subgroups living in various U.S. regions, with implications for informing the expansion and replication of the program in other regions of the country.     

北京市某高校社区妇女宫颈癌和乳腺癌筛查结果分析

目的 对北京市海淀区某高校社区4 171例妇女官颈癌和乳腺癌筛查结果进行分析,了解该地区妇女生殖健康状况,为今后制定妇女病防治措施提供依据.方法 对社区25～65岁妇女采用妇科常规检查和官颈液基脱落细胞学(TCT)检查的方法进行官颈癌筛查;对40 ～ 60岁妇女采用乳腺彩色多普勒超声的方法进行乳腺癌筛查.可疑病例转至定点医院进行复诊,并由专人负责随访.结果 参加官颈癌筛查4 171人,筛查率10.67％;妇科疾病患病率23.66％,其中子宫肌瘤患病率最高(11.00％);宫颈癌可疑转诊病例实访率98.53％.官颈上皮内瘤变患病率16.78/万;宫颈浸润癌患病率2.40/万.参加乳腺癌筛查3 110人,筛查率13.58％;乳腺疾病患病率28.01％,其中乳腺增生患病率最高,为14.05％;乳腺癌可疑转诊病例实访率为96.43％.乳腺癌患病率96.5/10万.结论 北京市某高校社区妇女官颈癌和乳腺癌筛查率均不高,定期进行筛查,对降低两癌的发病率和死亡率具有重要意义.     

Effects of screening on cervical cancer incidence and mortality in New South Wales implied by influences of period of diagnosis and birth cohort

STUDY OBJECTIVES: Cervical cancer incidence and mortality in NSW during 1972-1996 is examined under counterfactual assumptions to estimate the number of new cervical cancer cases averted and deaths avoided, with projections to 2006. SETTING: Cervical cancer incident cases and deaths in NSW for 1972-96 were obtained from the NSW Central Cancer Registry, Sydney, Australia. DESIGN: Data were analysed by age-period-cohort (APC) modelling, using Poisson regression. Projection of incidence to 2006 was based on a linear trend for period effects. A counterfactual scenario was constructed assuming stable period effects (1972-74), but modelled cohort effects. Modelled rates were converted to cases and deaths (using mortality:incidence ratios for cervical cancer), and compared with actual data to estimate cancers prevented and deaths averted due to screening. RESULTS: Rising cohort effects with recency of birth were found after controlling for age and period of diagnosis, and declining period effects were identified after controlling for age and birth cohort. The estimated cumulated number of new cases of cervical cancer prevented during 1972-1996 was 3440. The cumulated number of averted deaths over 1972-1996, derived from incident cases, was estimated to be 1610 (including actual declines in the M/I ratio). With no change in the M/I ratio from 1972, estimated cumulated mortality averted due to cervical cancer for 1972-1996 was 1210 deaths. CONCLUSIONS: Cervical screening has prevented a substantial number of new cases of cervical cancer and deaths. In addition, secondary prevention and improved treatment has contributed further to cervical cancer deaths averted.     

Esperanza y Vida: A Culturally and Linguistically Customized Breast and Cervical Education Program for Diverse Latinas at Three Different United States Sites

Breast cancer is the most common cause of cancer and the leading cause of cancer death among Latinas in the United States. In addition, Latinas experience a disproportionate burden of cervical cancer incidence, morbidity, and mortality compared with non-Hispanic White women. Lower use of breast and cervical cancer screening services may contribute to these disparities. To address the underutilization of breast and cervical cancer screening among diverse subgroups of Latinas, a peer-led education program called Esperanza y Vida (“Hope and Life”) was developed and administered at 3 sites (2 in New York and 1 in Arkansas). Immigrant Latina women and their partners were educated about the importance of breast and cervical cancer screening, with the goals of increasing their knowledge about these cancers and their screening behavior. An analysis of the intervention's findings at baseline among female participants demonstrated significant sociodemographic, interpersonal, cultural, health care system, and program variability in 3 distinct geographic regions in the United States. These data indicate the need for and feasibility of customizing cancer outreach and educational programs for diverse Latina subgroups living in various U.S. regions, with implications for informing the expansion and replication of the program in other regions of the country.     

Limited Pap screening associated with reduced risk of cervical cancer in South Africa

BACKGROUND: We investigated the effect of Pap smear screening on the incidence of invasive cancer of the cervix in the Western Cape, South Africa where screening is limited. METHODS: Data were derived from a case-control study of the association of hormonal contraceptives and invasive cervical cancer. Incident cases (n = 524) of invasive cervical cancer who presented at two tertiary hospitals and controls (n = 1540) series matched for age, race, and place of residence were interviewed. Information on a wide range of variables was collected including whether the women had previously had a Pap smear taken and the number and timing of smears. Odds ratios (OR) and 95% CI were calculated using multiple logistic regression. RESULTS: The OR of cervical cancer was reduced among women who had ever had a smear (OR = 0.3, 95% CI: 0.3-0.4). The OR declined with increasing number of smears to 0.2 for >/=>3 smears (trend P = 0.0003). Among women who had a smear <5 years previously the OR was 0.3, but even if the smear was taken >/=15 years previously the women remained at reduced risk (OR = 0.5). CONCLUSION: The data suggest that even limited Pap smear screening reduces the risk of cervical cancer. Should a screening programme be successfully implemented, the incidence of cervical cancer might be reduced by as much as 70%.     

Cervical Cancer among Asian American Women: A Neglected Publica Health Problem?

PURPOSE OF THE PAPER: Relatively little attention has been paid to cervical cancer control in Asian American populations. We summarize available cervical cancer incidence and mortality dat, present information on levels of Pap testing use, and review factors that may be associated with cervical cancer screening participation. METHODS: We reviewed the literature pertaining to cervical cancer and Pap testing among Asian populations in North America. PRINCIPAL FINDINGS: Cancer registry data suggest that women from Southease Asia have a nearly five­fold increased risk of invasive cervical cancer (when compared to non­Hispanic White women). Filipino and Korean populations also have elevated risks. The excess invasive cervical cancer burden appears to be concentrated among women aged 40 and older. Pap testing use by Asians is less than for all toher racial/ethnic groups in the U.S., and recent studies suggest that over one­third of Vietnamese immigrants have never been screened. Barriers to Pap testing participation by less acculturated Asian women include a lack of familiarity with Western preventive concepts, a lack of knowledge concerning cervical cancer, embarrassment in association with gynecologic exams, the role of women in some Asian cultures, the cost of health care, and language difficulties. CONCLUSIONS: There is a considerable need for ethnoculturally appropriate cervical cancer control programs targeting Asian American populations. RELEVANCE TO ASIAN PACIFIC ISLANDER AMERICAN POPULATIONS: This paper is relevant to Asian American women from East, South, Southeast, and Island Asia.     

探讨子宫颈癌的筛查方法

目的探讨子宫颈癌的筛查方法及临床效果。方法分析广东省妇幼保健院2328例妇女宫颈细胞筛查结果。结果传统巴氏细胞学检查病理阳性13例,检出率2．18％;液基细胞学检查病理阳性44例,检出率2．54％。传统巴氏检查微生物阳性28例,检出率4．71％;液基细胞学检查微生物阳性113例,检出率6．52％。传统巴氏检查的灵敏度是50％,液基检查的灵敏度是75％,二者比较差异具有统计学意义（P〈0．05）。结论液基细胞学检查方法在微生物阳性检出率、灵敏度等方面优于传统巴氏细胞学检查,筛查效果明显改善,将其用于子宫颈癌筛查在基层医院具有重要临床意义。     

宫颈细胞学涂片联合阴道镜检查筛查宫颈病变结果分析

目的:评价宫颈细胞学涂片联合阴道镜检查对子宫颈病变的诊断价值。方法:2003年10月～2006年10月采用宫颈细胞学涂片联合阴道镜检查筛查10326例患者,以组织学诊断为金标准对结果进行分析。结果:10326例中,阴道镜下活检1560例,异常涂片1379例(13.35%)。病理结果显示:急慢性炎症890例(8.62%),宫颈上皮内瘤样病变(CIN)414例(3.04%)。其中CINⅠ220例(2.13%),CINⅡ108例(1.05%),CINⅢ及原位癌86例(0.83%),宫颈浸润癌89例(0.86%),HPV感染155例(1.5%),子宫内膜异位症7例(0.07%),子宫肌瘤5例(0.05%)。宫颈细胞学检查诊断CIN符合率为64.04%,阴道镜检查为93.48%,两者比较差异显著性(χ2=103.13,P<0.005),两者联合对CIN检出率为4.01%。阴道镜诊断CIN的敏感性为93.48%,特异性为89.69%,两者联合对CIN的诊断阳性预测值为73.57%,阴性预测值为97.14%。结论:采用宫颈细胞学联合阴道镜下病理组织检查能提高宫颈癌前病变及早期宫颈癌的诊断率,在经济欠发达区域可作为宫颈病变的筛查方法,具有群防群治的重要价值。     

Invasive cervical cancer among Hispanic and non-Hispanic women--United States, 1992-1999

During 1973-1999, both the incidence of and death rates for cervical cancer decreased approximately 50% in the United States. For 2002, approximately 13,000 new cases of invasive cervical cancer are expected, and approximately 4,100 women will die of the disease. Although invasive cervical cancer can be prevented by regular screening, the prevalence of Papanicolaou (Pap) testing remains relatively low among minority populations such as Hispanic women. To characterize the incidence of invasive cervical cancer, CDC analyzed incidence data for Hispanic and non-Hispanic women during 1992-1999 in 11 geographic areas with population-based registries. This report summarizes the results of this analysis, which indicate that the incidence of invasive cervical cancer decreased for Hispanic and non-Hispanic women. However, among women aged > or = 30 years, cervical cancer incidence for Hispanic women was approximately twice that for non-Hispanic women. To lower the incidence of invasive cervical cancer, local health organizations should provide culturally appropriate public health interventions that encourage participation in readily accessible cervical cancer-screening programs.     

Incidence of invasive cervical cancer in the Swiss canton of Vaud, and a note on screening.

Age adjusted incidence rates (World standard) from invasive cervical cancer in the Swiss canton of Vaud decreased from 17.7/100,000 in 1968-70 to 9.9/100,000 in 1983-85. The decline was substantial in younger middle age, but no appreciable trend was observed in women over 70. This is consistent with available interview based information on the pattern of cervical screening in the Swiss population. Although there was no organised screening programme in Switzerland, over 80% of women aged 20-44 and 65% of those aged 45-64 reported one or more screening smears over the previous 3 years, compared to only 22% of women aged 65 or over. In the last calendar period, there was an apparent increase in the incidence of invasive cervical cancer (from 2.5 to 6.1/100,000) in women aged 25-29. Although based on small absolute numbers, this is in agreement with incidence and mortality data from other countries, and may therefore confirm a change in risk factor exposure in younger women.     

The German cervical cancer screening model: development and validation of a decision-analytic model for cervical cancer screening in Germany

BACKGROUND: We sought to develop and validate a decision-analytic model for the natural history of cervical cancer for the German health care context and to apply it to cervical cancer screening. METHODS: We developed a Markov model for the natural history of cervical cancer and cervical cancer screening in the German health care context. The model reflects current German practice standards for screening, diagnostic follow-up and treatment regarding cervical cancer and its precursors. Data for disease progression and cervical cancer survival were obtained from the literature and German cancer registries. Accuracy of Papanicolaou (Pap) testing was based on meta-analyses. We performed internal and external model validation using observed epidemiological data for unscreened women from different German cancer registries. The model predicts life expectancy, incidence of detected cervical cancer cases, lifetime cervical cancer risks and mortality. RESULTS: The model predicted a lifetime cervical cancer risk of 3.0% and a lifetime cervical cancer mortality of 1.0%, with a peak cancer incidence of 84/100,000 at age 51 years. These results were similar to observed data from German cancer registries, German literature data and results from other international models. Based on our model, annual Pap screening could prevent 98.7% of diagnosed cancer cases and 99.6% of deaths due to cervical cancer in women completely adherent to screening and compliant to treatment. Extending the screening interval from 1 year to 2, 3 or 5 years resulted in reduced screening effectiveness. CONCLUSIONS: This model provides a tool for evaluating the long-term effectiveness of different cervical cancer screening tests and strategies.     

Pap Smear Screening among Urban Southwestern American Indian Women

Background. American Indian women have among the highest incidence and mortality rates of cervix cancer in the United States. The incidence of cancer of the cervix among American Indians is 19.5/100,000 versus 7.8/100,000 in U.S. whites, and comparison by geographic region/tribe indicates that the rate is four to six times higher in some tribes. Papanicolaou cytological testing (Pap smear) permits the detection of cervical lesions before they become cancerous, effectively reducing the incidence of cervical cancer by 75–90%. The American Cancer Society recommends a Pap smear every year beginning at age 18 years or when sexually active, and more frequent screening in high-risk populations.Methods. A random household cross-sectional survey was conducted in Phoenix, Arizona, to assess cervical cancer screening rates among 519 adult urban American Indian women. Logistic regression was used to identify predictors of Pap smear use.Results. Three-quarters (76.1%) of urban women American Indian surveyed received a Pap smear within the past 3 years, but only 49.5% received a Pap smear within the last year. Women over age 50 years were significantly less likely to have received a recent Pap smear in comparison to younger women.Conclusions. The results of this study indicate that limited access to health care and lack of knowledge about the procedure were important barriers to Pap smear use. Improving cervix cancer screening participation rates is an important step in reducing the disease burden in this high-risk population.     

液基细胞学技术在宫颈病变筛查的应用现状及不足

宫颈癌发病率呈上升和年轻化趋势,宫颈癌的发生发展是一个漫长的过程,阻断这一过程是预防宫颈癌前病变及宫颈癌的主要途径。目前,液基细胞学(liquid-based cytology,LBC)技术是筛查宫颈病变最优质的检测方法,在宫颈细胞样本采集、制片以及阅片过程中采用了更先进的技术,克服以往巴氏涂片技术的不足,LBC技术的发展主要分为三个阶段,即新柏氏膜式薄层细胞学(ThinPrep Cytologic Test,TCT)、液基离心沉淀式薄层细胞学(AutoCyte Prep)和新柏氏影像系统(ThinPrep Imaging System,TIS)。液基细胞筛查技术应用于临床已明显降低宫颈癌的发病率和死亡率,但受到客观技术设施的影响,液基细胞筛查技术仍存在一些不足,如何弥补这一缺憾,人乳头瘤病毒(human papilloma virus,HPV)-脱氧核糖核酸(deoxyribonucleic acid,DNA)检测联合LBC检查作为宫颈病变筛查模式将成为未来的主流趋势。     

初善仪子宫颈癌筛查系统在宫颈病变筛查中的应用

宫颈癌是最常见的女性生殖道恶性肿瘤之一,是导致妇女死亡的第二大癌症,随着宫颈癌筛查的开展,宫颈癌的发病率及死亡率可明显下降。初善仪(TruScreen)是一种新型的宫颈病变筛查方法,它具有与病理学诊断的一致性好、敏感性特异性较高、简单无创、易携带、客观性和实时性等特点,还可以联合其它筛查方法[宫颈涂片、新柏式薄层液基细胞学技术(ThinPrep liquid-based cytology test,TCT)、液基细胞薄层涂片(liquid-based cytology test,LCT)、人乳头状瘤病毒检测(human papilloma virus test,HPV-test)等提高宫颈疾病的检出率,在宫颈癌及癌前病变筛查及预后判断具有重大的临床应用价值。