Open AccessAbnormal screens among nonmutation carriers in the High Risk Ontario Breast Screening Program
Author(s) -
Castelo Matthew,
Brown Zachary,
Schellenberg Angela E.,
Mills Jane K.,
Eisen Andrea,
Muradali Derek,
Grunfeld Eva,
Scheer Adena S.
Publication year - 2021
Publication title -
the breast journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.533
H-Index - 72
eISSN - 1524-4741
pISSN - 1075-122X
DOI - 10.1111/tbj.14185
Subject(s) - medicine , mammography , breast cancer , breast cancer screening , population , breast mri , cancer , gynecology , family medicine , obstetrics , environmental health
Abstract Background The Ontario Breast Screening Program was expanded in 2011 to offer annual MRI and mammography to women with high‐risk genetic mutations (e.g., BRCA1/2) and women with strong family histories and ≥25% estimated lifetime risk of breast cancer. Data to support high‐risk screening is less clear in the nonmutation carrier group, as MRI has lower specificity among this population. The potential unintended consequences may be considerable and need to be explored. We aimed to describe the frequency of abnormal screens and biopsies. Methods Demographic surveys and chart review consent were sent to a sample of 441 individuals enrolled in a high‐risk screening program at two tertiary care hospitals in Toronto, Ontario. Retrospective cross‐sectional chart review was undertaken for clinicopathologic data. The frequencies of abnormal screens and biopsies were calculated. Results One hundred sixty‐nine nonmutation carriers were included. The majority were white, employed, and highly educated. The median International Breast Cancer Intervention Study lifetime risk of breast cancer was 28.0% (range 24.5%–89.0%). 108 individuals (64%) experienced at least 1 abnormal screen and 13 (8%) had 3 or more over a median 3 years of screening (range 1–6 years). Of 55 biopsies, 3 (5.5%) were malignant. The cancer detection rate was 8.4/1000 screens (95% CI 3.2–22.4). Conclusions An MRI‐based screening program for nonmutation carriers was effective at diagnosing breast cancer. However, this population experienced a high rate of abnormal screens and intervention. Further research is needed to improve the performance of MRI‐based screening in these women.