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

Background: 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.

Investigations: Pedigree construction and BRCA1/2 mutation analysis.

Diagnosis: A BRCA2 8765delAG mutation was identified, in the context of unusual and sustained complete remission from widely metastatic breast cancer.

Management: 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.