中国城市女性乳腺癌筛查卫生经济学评价

  目的  探讨适合中国国情的乳腺癌筛查策略的成本效果。  方法  收集2008年2月至2011年12月基于中国前期多项全国女性乳腺癌筛查项目中的乳腺癌分期、筛查方法的准确性等临床和成本信息,及同期乳腺癌患者临床就诊信息。采用Markov模型系统评价132种乳腺癌筛查策略相对于不筛查的增量成本效果比。  结果  2010年与不筛查相比,40~64岁女性采用1次/2年的乳腺触诊与乳腺超声检查并联筛查策略,符合成本效果评价标准且效果最大。每10万女性采用该筛查策略进行筛查,累计可挽救1 394个质量调整寿命年（quality adjusted life year,QALY）。每挽救1个QALY的成本为91 944元。敏感性分析显示,2016年40~64岁女性采用1次/2年的乳腺触诊与乳腺X线检查并联筛查策略,符合成本效果评价标准且效果最大。在该筛查策略下,每挽救1个QALY的成本为159 637元。  结论  开展人群为基础的乳腺癌筛查项目相对符合中国当前国情。随着中国经济水平的不断提升,医疗水平的逐步改善,以及乳腺癌发病率的逐年上升,乳腺癌筛查的单位成本效果预期会有进一步的提高。      

Cost-effectiveness analysis of screening modalities for breast cancer in Japan with special reference to women aged 40-49 years

Although the introduction of screening mammography in Japan would be expected to reduce mortality from breast cancer, the optimal screening modality in terms of cost-effectiveness remains unclear. We compared the cost-effectiveness ratio, defined as the cost required for a life-year saved, among the following three strategies: (1) annual clinical breast examination; (2) annual clinical breast examination combined with mammography; and (3) biennial clinical breast examination combined with mammography for women aged 30-79 years using a hypothetical cohort of 100 000. The sensitivity, specificity and early breast cancer rates were derived from studies conducted from 1995 to 2000 in Miyagi Prefecture. The treatment costs were based on a questionnaire survey conducted at 13 institutions in Japan. We used updated parameters that were needed in the analysis. Although the effectiveness of treatment in terms of the number of expected survival years was highest for annual combined modality, biennial combined modality had a higher cost-effectiveness ratio, followed by annual combined modality and annual clinical breast examination in all age groups. In women aged 40-49 years, annual combined modality saved 852.9 lives and the cost/survival duration was 3 394 300 yen/year, whereas for biennial combined modality the corresponding figures were 833.8 and 2 025 100 yen/year, respectively. Annual clinical breast examination did not confer any advantages in terms of effectiveness (815.5 lives saved) or cost-effectiveness (3 669 900 yen/year). While the annual combined modality was the most effective with respect to life-years saved among women aged 40-49 years, biennial combined modality was found to provide the highest cost-effectiveness.     

Cost-effectiveness of opportunistic versus organised mammography screening in Switzerland

BackgroundVarious centralised mammography screening programmes have shown to reduce breast cancer mortality at reasonable costs. However, mammography screening is not necessarily cost-effective in every situation. Opportunistic screening, the predominant screening modality in several European countries, may under certain circumstances be a cost-effective alternative. In this study, we compared the cost-effectiveness of both screening modalities in Switzerland.MethodsUsing micro-simulation modelling, we predicted the effects and costs of biennial mammography screening for 50–69 years old women between 1999 and 2020, in the Swiss female population aged 30–70 in 1999. A sensitivity analysis on the test sensitivity of opportunistic screening was performed.ResultsOrganised mammography screening with an 80% participation rate yielded a breast cancer mortality reduction of 13%. Twenty years after the start of screening, the predicted annual breast cancer mortality was 25% lower than in a situation without screening. The 3% discounted cost-effectiveness ratio of organised mammography screening was €11,512 per life year gained. Opportunistic screening with a similar participation rate was comparably effective, but at twice the costs: €22,671–24,707 per life year gained. This was mainly related to the high costs of opportunistic mammography and frequent use of imaging diagnostics in combination with an opportunistic mammogram.ConclusionAlthough data on the performance of opportunistic screening are limited, both opportunistic and organised mammography screening seem effective in reducing breast cancer mortality in Switzerland. However, for opportunistic screening to become equally cost-effective as organised screening, costs and use of additional diagnostics should be reduced.     

Comparison of 1- and 2-year screening intervals for women undergoing screening mammography

We compared the long-term impact of 1- and 2-year screening mammography intervals using prognostic, screening, and outcome information for women aged 50-74 years obtained from the Screening Mammography Program of British Columbia in two time periods, prior to 1997 (policy of annual mammography) and after 1997 (biennial mammography). Survival was estimated for both periods using a prognostic model and the expected rate of interval and screen-detected cancers. The likelihood of a screen-detected cancer with annual screening was 2.32 per thousand screens and with biennial screening was 3.32 per thousand screens. The prognostic profile of screen-detected cancers was better than that of interval cancers. Among both screen-detected and interval cancers, the prognostic profiles with annual and biennial screening were similar. The estimated breast cancer-specific survival rates for women undergoing annual and biennial screening mammography were 95.2 and 94.6% at 5 years, and 90.4 and 89.2% at 10 years, respectively. Annual compared to biennial mammography was associated with a 1.2% increase in the estimated 10-year breast cancer-specific survival for women aged 50-74 years, diagnosed with invasive breast cancer after screening programme attendance.     

Breast cancer screening, outside the population-screening program, of women from breast cancer families without proven BRCA1/BRCA2 mutations: a simulation study.

PURPOSE: We assessed the cost-effectiveness of mammography screening for women under the age of 50, from breast cancer families without proven BRCA1/BRCA2 mutations, because current criteria for screening healthy women from breast cancer families are not evidence-based. METHODS: We did simulation studies with mathematical models on the cost-effectiveness of mammography screening of women under the age of 50 with breast cancer family histories. Breast cancer screening was simulated with varying screening intervals (6, 12, 18, and 24 months) and screening cohorts (starting at ages 30, 35, 40, and 45, and continuing to age 50). Incremental costs of screening were compared with those of women ages 50 to 52 years, the youngest age group currently routinely screened in the nationwide screening program of the Netherlands, to determine cost-effectiveness. Sensitivity analyses were done to explore the effects of model assumptions. The cost-effectiveness of breast cancer screening for women over the age of 50 was not debated. RESULTS: The most effective screening interval was found to be 12 months, which, however, seems only to be cost-effective in a small group of women under the age of 50 with at least two affected relatives, including at least one affected in the first degree diagnosed under the age of 50. Significantly, early breast cancer screening never seemed to be cost-effective in women with only one affected first-degree or second-degree relative. CONCLUSION: Annual breast cancer screening with mammography for women under the age of 50 seems to be cost-effective in women with strong family histories of breast cancer, even when no BRCA1/BRCA2 mutation was found in affected family members.     

Mammography Screening and Breast Cancer Mortality in New South Wales, Australia

OBJECTIVE: To investigate the relationship between utilisation of service mammography screening and breast cancer mortality in New South Wales (NSW) women. Setting : Population-based biennial mammography screening was progressively introduced in NSW from 1988, with active recruitment and re-invitation for women aged 50-69 years, and reached full geographic coverage by 1996. Biennial mammography screening participation has varied widely over time and by municipality. METHODS: Breast cancer mortality by age, period and municipality was obtained from the NSW Central Cancer Registry. Biennial mammography screening rates for the same strata were obtained from the BreastScreen NSW database. Temporal changes in breast cancer mortality for NSW were summarised as annual average declines using Poisson regression. Breast cancer mortality for 1997-2001 was examined in relation to lagged biennial screening rates by municipality, adjusted for age, area socio-economic and geographic indicators, and breast cancer incidence, also using Poisson regression. RESULTS: For the 50-69 year age group, the mean annual breast cancer mortality decline was 0.8% (not significant) for 1988-1994, and 4.4% (p < 0.0001) for 1995-2001. Statistically significant negative associations between breast cancer mortality in 1997-2001 and lagged biennial screening rates were found with the highest significance at a four-year lag for women aged 50-69 years ( p = 0.0003) and also for women aged 50-79 years (p c = 0.0002). From the regression coefficient, a 70% biennial screening rate is associated with 32% lower breast cancer mortality (compared to zero screening). CONCLUSIONS: The effect of population-based mammography screening on breast cancer mortality in NSW inferred using this method is consistent with results of trials and other service studies. This suggests that population-based mammography screening programs can achieve significant reductions in breast cancer mortality with adequate participation.     

The association between the pre-diagnosis mammography screening interval and advanced breast cancer

BACKGROUND: While screening has been demonstrated to reduce breast cancer mortality, the optimal screening interval is unknown. We designed a study to determine the risk of an advanced breast cancer diagnosis by varying the interval between mammograms. METHODS: We reviewed a single state's mammography records of women diagnosed with breast cancer between 1994 and 2002. The pre-diagnosis screening interval was the number of days between the last two eligible mammograms preceding a cancer diagnosis. The interval was classified as annual (0.75-1.49 years), biennial (1.5-2.49 years) or longer (exceeding 2.49 years). Advanced breast cancer was >or=stage IIB, tumor size >2 cm, or >or=one lymph node with cancer. RESULTS: The probability of an advanced breast cancer diagnosis did not differ between women with an annual pre-diagnosis screening interval and women with a biennial interval (21.1% vs. 23.7%, P=0.262). A longer pre-diagnosis screening interval was weakly associated with advanced breast cancer (21.8% for intervals 0.75-2.49 years vs. 26.8% for longer intervals, P=0.070). In multivariate analysis, we found an interaction between the pre-diagnosis screening interval and age. Among women 50 years or older, the risk of an advanced breast cancer diagnosis risk was higher for women with a pre-diagnosis screening interval exceeding 2.49 years compared to women with shorter screening intervals (OR 1.99 [1.02-3.90]). CONCLUSIONS: We found no difference in advanced breast cancer rates between women using mammography annually or biennially. Among women 50 years or older, the advanced breast cancer rate increased when the pre-diagnosis screening interval exceeded 2.49 years.     

Cost‐effectiveness of digital mammography screening before the age of 50 in The Netherlands

In the Netherlands, routine mammography screening starts at age 50. This starting age may have to be reconsidered because of the increasing breast cancer incidence among women aged 40 to 49 and the recent implementation of digital mammography. We assessed the cost‐effectiveness of digital mammography screening that starts between age 40 and 49, using a microsimulation model. Women were screened before age 50, in addition to the current programme (biennial 50–74). Screening strategies varied in starting age (between 40 and 50) and frequency (annual or biennial). The numbers of breast cancers diagnosed, life‐years gained (LYG) and breast cancer deaths averted were predicted and incremental cost‐effectiveness ratios (ICERs) were calculated to compare screening scenarios. Biennial screening from age 50 to 74 (current strategy) was estimated to gain 157 life years per 1,000 women with lifelong follow‐up, compared to a situation without screening, and cost €3,376/LYG (3.5% discounted). Additional screening increased the number of LYG, compared to no screening, ranging from 168 to 242. The costs to generate one additional LYG (i.e., ICER), comparing a screening strategy to the less intensive alternative, were estimated at €5,329 (biennial 48–74 vs. current strategy), €7,628 (biennial 45–74 vs. biennial 48–74), €10,826 (biennial 40–74 vs. biennial 45–74) and €18,759 (annual 40–49 + biennial 50–74 vs. biennial 40–74). Other strategies (49 + biennial 50–74 and annual 45–49 + biennial 50–74) resulted in less favourable ICERs. These findings show that extending the Dutch screening programme by screening between age 40 and 49 is cost‐effective, particularly for biennial strategies.     

中国妇女乳腺X线钼靶摄影普查成本效益分析

目的:分析中国妇女乳腺X线钼靶摄影普查的成本效益.方法:结合中国妇女的人群年龄结构以及乳腺癌相关数据,利用Markov模型模拟乳腺癌发展过程,结合每一种状态的成本消耗和健康收益,通过10个周期(每个周期为1年)的循环运算,分析乳腺X线钼靶摄影普查的成本效益.结果:35～59岁人群的普查增量成本效益比(incremental cost-effectiveness ratio,ICER)为216 656.00元/质量调整生命年(quality adjusted life year,Q ALY),普查可降低乳腺癌死亡率14.66％; 35～69岁人群的普查ICER为248727.50元/QALY,普查可降低乳腺癌死亡率14.79％.ICER与乳腺癌发病率、X线钼靶摄影检查的敏感度和特异度以及检查费用等密切相关.结论:中国女性采用乳腺癌普查可降低乳腺癌死亡率约15％.根据当前中国女性乳腺癌发病率、普查平均效能(敏感度和特异度)以及检查成本,全国乳腺癌普查暂不具成本效益.鉴于普查的成本效益与发病率、普查效能以及普查中的检查价格密切相关,因此随着乳腺癌发病率的提高、普查中检查价格的降低以及普查敏感度或特异度的提高,中国妇女的乳腺癌普查将具有成本效益甚至极具成本效益.     

The National Cancer Screening Program for Breast Cancerin the Republic of Korea: Is it Cost-Effective?

This goal of this research was to evaluate the cost-effectiveness of the National Cancer ScreeningProgram (NCSP) for breast cancer in the Republic of Korea from a government expenditure perspective. In2002-2003 (baseline), a total of 8,724,860 women aged 40 years or over were invited to attend breast cancerscreening by the NCSP. Those who attended were identified using the NCSP database, and women weredivided into two groups, women who attended screening at baseline (screened group) and those who did not(non-screened group). Breast cancer diagnosis in both groups at baseline, and during 5-year follow-up wasidentified using the Korean Central Cancer Registry. The effectiveness of the NCSP for breast cancer wasestimated by comparing 5-year survival and life years saved (LYS) between the screened and the unscreenedgroups, measured using mortality data from the Korean National Health Insurance Corporation and theNational Health Statistical Office. Direct screening costs, indirect screening costs, and productivity costs wereconsidered in different combinations in the model. When all three of these costs were considered together,the incremental cost to save one life year of a breast cancer patient was 42,305,000 Korean Won (KW)(1 USD=1,088 KW) for the screened group compared to the non-screened group. In sensitivity analyses,reducing the false-positive rate of the screening program by half was the most cost-effective (incrementalcost-effectiveness ratio, ICER=30,110,852 KW/LYS) strategy. When the upper age limit for screening wasset at 70 years, it became more cost-effective (ICER=39,641,823 KW/LYS) than when no upper age limitwas set. The NCSP for breast cancer in Korea seems to be accepted as cost-effective as ICER estimates werearound the Gross Domestic Product. However, cost-effectiveness could be further improved by increasingthe sensitivity of breast cancer screening and by setting appropriate age limits.     

Benefits and harms of mammography screening

Mammography screening for breast cancer is widely available in many countries. Initially praised as a universal achievement to improve women''s health and to reduce the burden of breast cancer, the benefits and harms of mammography screening have been debated heatedly in the past years. This review discusses the benefits and harms of mammography screening in light of findings from randomized trials and from more recent observational studies performed in the era of modern diagnostics and treatment. The main benefit of mammography screening is reduction of breast-cancer related death. Relative reductions vary from about 15 to 25% in randomized trials to more recent estimates of 13 to 17% in meta-analyses of observational studies. Using UK population data of 2007, for 1,000 women invited to biennial mammography screening for 20 years from age 50, 2 to 3 women are prevented from dying of breast cancer. All-cause mortality is unchanged. Overdiagnosis of breast cancer is the main harm of mammography screening. Based on recent estimates from the United States, the relative amount of overdiagnosis (including ductal carcinoma in situ and invasive cancer) is 31%. This results in 15 women overdiagnosed for every 1,000 women invited to biennial mammography screening for 20 years from age 50. Women should be unpassionately informed about the benefits and harms of mammography screening using absolute effect sizes in a comprehensible fashion. In an era of limited health care resources, screening services need to be scrutinized and compared with each other with regard to effectiveness, cost-effectiveness and harms.     

Mammographic screening after the age of 65 years: early outcomes in the Nijmegen programme.

We studied outcomes of mammographic screening in women older than 65 years. In 1975, breast cancer screening was started in Nijmegen, The Netherlands, for women aged 35-65 years. Since 1977, approximately 7700 older women have also been invited for biennial one-view mammography. This report is based on ten screening rounds from 1975 to 1994. The results of the subsequent screening rounds in the age groups 65-69 years, 70-74 years and 75 years and older were: participation rates 55%, 39% and 15%; screen-detected cancer rates 5.6%, 6.9% and 7.8%; interval cancer rates 2.0%, 1.8%, and 3.5%; and predictive values of referral 62%, 64% and 62% respectively. In all age groups, screen-detected patients had smaller tumours and a lower prevalence of axillary lymph node involvement than unscreened patients. Our conclusion is that, in women aged 65 years, and older, breast cancer can be detected at an earlier stage by mammographic screening.     

Effective biennial mammographic screening in women aged 40-49

BackgroundThe United Kingdom is currently moving the age limit for invitation in its national breast screening programme downwards from 50 to 47. In contrast, the US Preventive Services Task Force concluded that, because of borderline statistical significance on effectiveness of mammographic screening, the current evidence is insufficient to advise screening in women aged 40–49.Material and methodsWe designed a case-referent study to investigate the effect of biennial mammographic screening on breast cancer mortality for women in their forties. In Nijmegen, the Netherlands, screening started in 1975. A total of 272 breast cancer deaths were identified, and 1360 referents aged 40–69 were sampled from the population invited for screening. Effectiveness was estimated by calculating the odds ratio (OR) indicating the breast cancer death rate in screened versus unscreened women.ResultsIn women aged 40–49, the effect of screening was OR = 0.50 (95% confidence interval (CI) = 0.30–0.82). This result is similar to those aged 50–59 (OR = 0.54; 95% CI = 0.35–0.85) and 60–69 (OR = 0.65; 95% CI = 0.38–1.13).ConclusionOur results add convincing evidence about the effectiveness of biennial mammographic screening in women aged 40–49.     

The effects of population‐based mammography screening starting between age 40 and 50 in the presence of adjuvant systemic therapy

Adjuvant systemic therapy has been shown to be effective in reducing breast cancer mortality. The additional effect of mammography screening remains uncertain, in particular for women aged 40–49 years. We therefore assessed the effects of screening starting between age 40 and 50, as compared to the effects of adjuvant systemic therapy. The use of adjuvant endocrine therapy, chemotherapy and the combination of endocrine‐ and chemotherapy, as well as the uptake of mammography screening in the Netherlands was modeled using micro‐simulation. The effects of screening and treatment were modeled based on randomized controlled trials. The effects of adjuvant therapy, biennial screening between age 50 and 74 in the presence of adjuvant therapy, and extending the screening programme by starting at age 40 were assessed by comparing breast cancer mortality in women aged 0–100 years in scenarios with and without these interventions. In 2008, adjuvant treatment was estimated to have reduced the breast cancer mortality rate in the simulated population by 13.9%, compared to a situation without treatment. Biennial screening between age 50 and 74 further reduced the mortality rate by 15.7%. Extending screening to age 48 would lower the mortality rate by 1.0% compared to screening from age 50; 10 additional screening rounds between age 40 and 49 would reduce this rate by 5.1%. Adjuvant systemic therapy and screening reduced breast cancer mortality in similar amounts. Expanding the lower age limit of screening would further reduce breast cancer mortality.     

Risk stratification in breast cancer screening: Cost-effectiveness and harm-benefit ratios for low-risk and high-risk women

In mammography screening programmes, women are screened according to a one-size-fits-all principle. Tailored screening, based on risk levels, may lead to a better balance of benefits and harms. With microsimulation modelling, we determined optimal mammography screening strategies for women at lower (relative risk [RR] 0.75) and higher (RR 1.8) than average risk of breast cancer, eligible for screening, using the incremental cost-effectiveness ratio (ICER) of current uniform screening in the Netherlands (biennial [B] 50-74) as a threshold ICER. Strategies varied by interval (annual [A], biennial, triennial [T]) and age range. The number of life-years gained (LYG), breast cancer deaths averted, overdiagnosed cases, false-positive mammograms, ICERs and harm-benefit ratios were calculated. Optimal risk-based screening scenarios, below the threshold ICER of €8883/LYG, were T50-71 (€7840/LYG) for low-risk and B40-74 (€6062/LYG) for high-risk women. T50-71 screening in low-risk women resulted in a 33% reduction in false-positive findings, a similar reduction in costs and improved harm-benefit ratios compared to the current screening schedule. B40-74 in high-risk women led to an increase in screening benefit, compared to current B50-74 screening, but a relatively higher increase in false-positive findings. In conclusion, optimal screening consisted of a longer interval and lower stopping age than current uniform screening for low-risk women, and a lower starting age for high-risk women. Extending the interval for women at lower risk from biennial to triennial screening reduced harms and costs while maintaining most of the screening benefit.     

Impact of screening mammography on mortality from breast cancer before age 60 in women 40 to 49 years of age

Background

Whether screening mammography programs should include women in their 40s is controversial. In Canada, screening of women aged 40–49 years has not been shown to reduce mortality from breast cancer. Given that screening mammography reduces mean tumour size and that tumour size is inversely associated with survival, the lack of benefit seen with screening is puzzling and suggests a possible adverse effect on mortality of mammography or subsequent treatment (or both) that counterbalances the expected benefit derived from downstaging.

Methods

We followed 50,436 women 40–49 years of age until age 60 for mortality from breast cancer. Of those women, one half had been randomly assigned to annual mammography and one half to no mammography. The impact of mammography on breast cancer mortality was estimated using a left-censored Cox proportional hazards model.

Results

Of 256 deaths from breast cancer recorded in the study cohort, 134 occurred in women allocated to mammography, and 122 occurred in those receiving usual care and not allocated to mammography. The cumulative risk of death from breast cancer to age 60 was 0.53% for women assigned to mammography and 0.48% for women not so assigned. The hazard ratio for breast cancer–specific death associated with 1 or more screening mammograms before age 50 was 1.10 (95% confidence interval: 0.86 to 1.40).

Conclusions

Mammography in women 40–49 years of age is associated with a small but nonsignificant increase in the risk of dying of breast cancer before age 60. Caution should be exercised when recommending mammographic screening to women before age 50.     

Population-based mammography screening below age 50: balancing radiation-induced vs prevented breast cancer deaths

Introduction:

Exposure to ionizing radiation at mammography screening may cause breast cancer. Because the radiation risk increases with lower exposure age, advancing the lower age limit may affect the balance between screening benefits and risks. The present study explores the benefit–risk ratio of screening before age 50.

Methods:

The benefits of biennial mammography screening, starting at various ages between 40 and 50, and continuing up to age 74 were examined using micro-simulation. In contrast with previous studies that commonly used excess relative risk models, we assessed the radiation risks using the latest BEIR-VII excess absolute rate exposure-risk model.

Results:

The estimated radiation risk is lower than previously assessed. At a mean glandular dose of 1.3 mGy per view that was recently measured in the Netherlands, biennial mammography screening between age 50 and 74 was predicted to induce 1.6 breast cancer deaths per 100 000 women aged 0–100 (range 1.3–6.3 extra deaths at a glandular dose of 1–5 mGy per view), against 1121 avoided deaths in this population. Advancing the lower age limit for screening to include women aged 40–74 was predicted to induce 3.7 breast cancer deaths per 100 000 women aged 0–100 (range 2.9–14.4) at biennial screening, but would also prevent 1302 deaths.

Conclusion:

The benefits of mammography screening between age 40 and 74 were predicted to outweigh the radiation risks.     

MRI screening for breast cancer in women with familial or genetic predisposition: design of the Dutch National Study (MRISC)

Mammography screening of women aged 50–70 years for breast cancer has proven to be effective in reducing breast cancer mortality. There is no consensus about the value of breast cancer screening in women aged 40–49 years. Five to ten per cent of all breast cancers are hereditary. One of the options to reduce the risk of breast cancer mortality for women with a familial or genetic predisposition is intensive surveillance. However, the effectiveness of mammography screening for breast cancer in these women, who are mainly younger than 50 years, is unproven. MRI might increase the effectiveness of screening in women with a familial or genetic predisposition. This paper describes the design of the Dutch national study for Magnetic Resonance Imaging (MRI) screening in women with a familial or genetic predisposition. The aims of this study are to investigate: the value of regular surveillance in women with a familial or genetic predisposition for breast cancer, the efficacy of MRI as compared to mammography, cost-effectiveness of regular screening and quality of life during surveillance. Included are women with a lifetime risk of familial breast cancer of 15% or more or BRCA1/2 mutation carriers, who visit one of the Dutch family cancer clinics. The aim is to include 2,500 women. The study started on 1 November 1999. On 1 January 2002, more than 1700 women, including 210 proven carriers of a BRCA1 or BRCA2 mutation, were included in the study.     

A model-based comparison of breast cancer screening strategies: mammograms and clinical breast examinations.

In screening for secondary prevention of breast cancer, clinical breast examination (CBE) combined with mammography may improve overall screening sensitivity compared with mammography alone. A systematic evaluation of the relative expenses and projected benefit of combining these two screening modalities is not presently available. We addressed this issue using a microsimulation model incorporating age-specific preclinical duration of the disease, age-specific sensitivities of the two modalities, age-specific incidence of the disease, screening strategy, and competing causes of mortality. We examined a total of 48 screening strategies, depending on the age range, the examination interval, and whether mammography or CBE is given at every one or two exam. Our results indicate that a biennial mammography can be cost-effective if coupled with annual CBE. For each screening interval and starting age, giving mammography every two exams and CBE at every exam has the lowest marginal cost per year of quality-adjusted life saved, whereas giving both at every exam has the highest. Comparing annual mammography and CBE to biennial mammography and annual CBE from 50 to 79, the total cost was reduced by 35%, whereas the marginal quality-adjusted life years only decreased by 12%. Similar reductions are observed for other starting ages. It is cost-effective to have a biennial mammography if coupled with an annual CBE. Annual mammography combined with CBE every 6 months will lead to a 41% increase in the quality-adjusted life years compared with annual mammography and CBE from 50 to 79, whereas the total cost increases by 30%.     

不同钼靶X线阳性标准对乳腺癌筛查成本效果的影响

  目的  根据乳腺癌筛查数据, 比较不同钼靶X线阳性判定标准对其筛查成本效果的影响, 为国家制定乳腺癌筛查方案提供参考。  方法  在2008年7月到2009年9月, 对天津、南昌、肥城和沈阳4个城市开展了一个横断面多中心的乳腺癌筛查研究项目。其中21 986例45~69岁年龄组的妇女进行了乳腺钼靶X线检查, 经过1年随访, 最后65例乳腺癌新发病例被确诊。根据不同钼靶X线检查阳性判定标准计算其各自的灵敏度和特异度。利用马尔科夫模型模拟整个筛查过程, 计算各自的成本效果比值并对其进行敏感性分析。模拟筛查过程时, 对其进行了3%的折扣。成本效果比值用挽救每个生命年所花的费用来表示, 即: ￥/ LYs（life years saved）。  结果  将BIRADS分级0级（需进一步影像检查或与前次影像资料比较才能得出结论）归为阴性, 筛查出55例乳腺癌, 灵敏度为84.6%, 特异度为98.6%, 成本效果比值为45 632￥/LYs; 若0级为阳性, 筛查出56例乳腺癌, 灵敏度为86.2%, 特异度为93.9%, 成本效果比值为52 392￥/LYs。  结论  不同的钼靶X线阳性判定标准对其灵敏度影响较小, 对特异度和成本效果影响较大。