Appropriateness of breast‐conserving treatment of breast carcinoma in women with germline mutations in BRCA1 or BRCA2

Abstract

BACKGROUND Although BRCA1 and BRCA2 were identified in 1994 and 1995, respectively, to the authors' knowledge the optimal management of women with BRCA-associated breast carcinoma remains incompletely defined. The current study evaluates the appropriateness of breast-conserving therapy (BCT) in women with BRCA mutations. METHODS Between May 1992 and October 2003, 87 female participants in genetic testing protocols were identified who 1) were found to have deleterious germline BRCA mutations and 2) reported a history of invasive breast carcinoma that was treated with wide local excision and radiation therapy. Clinical records were reviewed and follow-up was updated. RESULTS The 87 subjects underwent BCT for 95 invasive breast tumors (8 women received BCT for metachronous bilateral tumors). In all 95 treated breasts, the 5-year and 10-year probabilities of metachronous ipsilateral breast carcinoma (MIBC) were 11.2% and 13.6%, respectively. Among the 87 subjects, the 5-year and 10-year probabilities of metachronous contralateral breast carcinoma (CBC) after treatment of the index tumor were 11.9% and 37.6%. No clinical factors were identified that were associated with either MIBC or CBC, including the use of tamoxifen or chemotherapy. CONCLUSIONS Women with BRCA-associated breast carcinoma who undergo BCT appear to have risks of MIBC that are similar to those reported for young women without known mutations. The indications for unilateral mastectomy in this group of women should be the same as those for women with nonhereditary carcinoma. However, significant risks of CBC and possibly late MIBC may prompt the serious consideration of bilateral mastectomy as a preventive measure. Cancer 2005. © 2004 American Cancer Society.