Abstract
Introduction: The surveillance scheme for early detection of breast cancer (BC) in BRCA1/BRCA2 (=BRCA) PSV-carriers in Israel includes semi-annual imaging: MRI alternating with ultrasound (US) from age 25 to 29 years, with mammography (MG) replacing US from age 30 onwards. The purpose of the study was to assess the added value and yield of MG/US to annual screening MRI in the surveillance scheme of young BRCA PSV-carriers when BC was diagnosed ≤ 35 years of age. Methods: This retrospective study encompassed female BRCA PSV-carriers attending the Meirav high-risk clinic at Sheba Medical Center, who were diagnosed with BC ≤ 35 years after joining the clinic between 2010-2023. Relevant clinical, radiological, pathological, genetic data, and imaging modalities used, were retrieved from the computerized-archiving system, using an IRB-approved protocol. Results: Overall, 28/1375 BRCA PSV-carriers undergoing surveillance at the clinic during the study period met the inclusion criteria: 24/28(86%) were BRCA1 and 4/28(14%) were BRCA2 PSV-carriers. In 17/28 (61%) BC was diagnosed by screening MRI and in 11/28 (39%) by MG/US (p>0.05), of whom 7 underwent MG/US because they were either pregnant or breastfeeding. In the group diagnosed by MG/US, 5/11 had a palpable mass (interval cancers), and none in the MRI group. In 17/24 non-pregnant patients, BC was diagnosed by MRI (p=0.03). Mean MRI-diagnosed tumor size was 12.5 ± 6.2 mm (range 5-30mm) and 24.6 ± 13.8 mm for MG/US based diagnosed tumors (range 6-50mm) (p=0.003). Conclusion: In the current study, young (≤ 35 years) BRCA PSV-carriers diagnosed with BC were effectively diagnosed by MRI screening, and MRI-diagnosed BCs were smaller than MG/US-diagnosed BC. Thus, it seems that MRI screening is sufficient for early stage BC detection in young, non-pregnant or breastfeeding BRCA PSV-carriers with no palpable breast mass. For pregnant BRCA PSV-carriers, US surveillance seems important to minimize risk for interval cancers.
