Dalla Lana School of Public Health, Division of Epidemiology, University of Toronto, Toronto, Ontario, Canada.
Dalla Lana School of Public Health, Division of Epidemiology, University of Toronto, Toronto, Ontario, Canada.
Genet Med. 2023 Jun;25(6):100820. doi: 10.1016/j.gim.2023.100820. Epub 2023 Mar 12.
Women with a remaining lifetime risk of breast cancer of ≥25%, estimated using the International Breast Cancer Intervention Study (IBIS) model, were eligible for the High Risk Ontario Breast Screening Program. This study examined the performance of IBIS 10-year risk estimates in the program.
This retrospective study included 7487 women aged 30 to 69 years referred to the High Risk Ontario Breast Screening Program between July 1, 2011, and December 31, 2016, with follow-up until December 31, 2018. Model calibration and discrimination were assessed. Analyses were conducted overall and stratified by age (< or ≥50 years). Different 10-year risk thresholds were compared with the current eligibility criteria.
Overall, IBIS overestimated the risk of breast cancer with an expected vs observed case ratio of 1.17 (95% CI = 1.04-1.35). Overestimation was highest in women aged 50 to 69 years (expected vs observed case ratio = 1.29, 95% CI = 1.03-1.69) and for those in the top quartile of risk. Overall discrimination was fair with a concordance statistic of 0.66 (95% CI = 0.63-0.70). Furthermore, when using different 10-year risk eligibility thresholds, most cases would have been missed in the 30 to 49 age group using the 8% 10-year risk threshold, whereas relatively few women aged 50 to 69 would have been ineligible at any of the thresholds examined.
We found that IBIS overestimated the risk of breast cancer in this screening cohort but had adequate discrimination. Age-specific risk thresholds should be considered to optimize the program eligibility criteria.
采用国际乳腺癌干预研究（IBIS）模型估计终生乳腺癌风险≥25%的女性有资格参加安大略高危乳腺癌筛查计划。本研究旨在检验该模型在该计划中的 10 年风险预测表现。
本回顾性研究纳入了 2011 年 7 月 1 日至 2016 年 12 月 31 日期间转诊至安大略高危乳腺癌筛查计划的 7487 名 30 至 69 岁的女性，随访至 2018 年 12 月 31 日。评估模型校准和区分度。总体分析及按年龄（< 50 岁或≥50 岁）分层分析。将不同的 10 年风险阈值与当前的纳入标准进行比较。
总体而言，IBIS 对乳腺癌风险的预测值高于实际值，预期病例与实际病例的比值为 1.17（95%可信区间[CI]：1.04-1.35）。在 50 至 69 岁的女性中高估程度最高（预期病例与实际病例的比值为 1.29，95%CI：1.03-1.69），且在风险最高的四分位数中高估程度最高。总体区分度尚可，一致性指数为 0.66（95%CI：0.63-0.70）。此外，当使用不同的 10 年风险纳入阈值时，在 30 至 49 岁年龄组中，使用 8%的 10 年风险阈值会导致大多数病例被漏诊，而在任何一个检查的阈值中，50 至 69 岁的女性相对较少被排除在外。
我们发现，IBIS 对该筛查队列中的乳腺癌风险预测过高，但具有足够的区分度。应考虑采用年龄特异性风险阈值来优化该计划的纳入标准。
