Background: Most commonly, mortality is used for evaluation of organized breast cancer screening programmes. Survival analyses are also being employed to provide more timely assessment. A novel approach has been introduced for calculating survival using Slovenian data.Methods: Breast cancer cases from the Slovenian Cancer Registry between 2008–2021 in women aged 50 to 72 were included, supplemented by data on the screening history from the screening registry. The comparison was made in two scenarios—invited or not invited to the screening. Survival, years of life gained, and number of avoided deaths over 10 years were calculated and standardized. The comparison was adjusted for confounding covariates, and a biological tumour growth model was used to adjust the survival of the invited group for lead time bias and over-detection.Results: A total of 9392 breast cancer cases were included in the study. Estimated median lead time for screen-detected cases was 1.23 years. The survival probability accounting for lead time bias and covariates of cancers patients invited to the programme was 4.3 percentage points higher than the not invited (0.81 vs. 0.76). Standardized to 100,000 women in the 2-year period, this would result in 22 avoided deaths. On average, the invited cancer patient lived 0.22 years longer, which amounts to a total of 114 years of life gained.Conclusions: The results show the overall benefit of the breast cancer screening programme. The standardized results enable cross-country comparisons. The calculation of years of life gained and avoided deaths can provide additional opportunities for communicating the results to non-expert populations.
背景：目前对乳腺癌筛查项目的评估主要采用死亡率指标。生存分析也被用于提供更及时的评估。本研究基于斯洛文尼亚数据，引入了一种计算生存率的新方法。 方法：研究纳入2008-2021年间斯洛文尼亚癌症登记系统中50-72岁女性乳腺癌病例，并整合筛查登记系统的筛查史数据。通过两种情境进行比较——受邀筛查组与未受邀筛查组。计算并标准化了10年生存率、获得生命年数及避免死亡数。分析中对混杂协变量进行校正，并采用肿瘤生物学生长模型对受邀组的生存数据进行领先时间偏倚和过度检测的校正。 结果：研究共纳入9392例乳腺癌病例。筛查检出病例的中位领先时间估计为1.23年。经领先时间偏倚和协变量校正后，受邀参与筛查项目的癌症患者生存概率比未受邀组高4.3个百分点（0.81比0.76）。按两年期内10万女性人口标准化计算，相当于避免了22例死亡。受邀筛查的癌症患者平均延长生存期0.22年，总计获得114个生命年。 结论：研究结果证实了乳腺癌筛查项目的总体效益。标准化结果支持跨国比较。获得生命年数和避免死亡数的计算为向非专业人群传达筛查效益提供了新的沟通维度。
肿瘤(癌症)患者之家