Eleven years disease-free: role of chemotherapy in metastatic BRCA2-related breast cancer

Abstract

Infiltrating ductal carcinoma of the breast, staged as pT1N3, was diagnosed in a 41-year-old premenopausal French-Canadian woman. Rapid nodal recurrence progressed to diffuse bone metastases, despite tamoxifen and megestrol. Following enrollment in an in-house study protocol, she received high-dose anthracycline-based induction chemotherapy followed by tandem autologous bone marrow transplantation with high-dose alkylator and platinum-based conditioning regimens. Upon full remission, protocol-mandated locoregional breast and prophylactic cranial radiation was delivered. Complete clinical and radiologic remission has been maintained in the 11 years since study enrolment, which prompted further investigation. Pedigree construction and BRCA1/2 mutation analysis. A BRCA2 8765delAG mutation was identified, in the context of unusual and sustained complete remission from widely metastatic breast cancer. The patient is now followed at a multidisciplinary high-risk prevention clinic because BRCA2 mutations are associated with increased risk of ovarian and breast cancers. This case supports the possibility of differential treatment response in BRCA2-positive breast cancer, although this remains to be conclusively demonstrated.