Mastectomy vs. Lumpectomy in Hereditary Breast Cancer

摘要

Introduction: Two genes for hereditary breast cancer, BRCA1 and BRCA2, have now been identified (Miki et al, 1994, Wooster et al, 1995). The lifetime risk for breast cancer exceeds 80% in carriers of mutations in either of these genes (Ford et al, 1994). The risk of second primary breast cancer in women with BRCA1 or BRCA2 mutations is high. Up to 60% of carriers will develop a contralateral cancer if they survive the initial cancer (Ford et al, 1994). There is no information yet on how different treatments (including surgery, chemotherapy, radiation therapy, oophorectomy, and tamoxifen therapy) impact upon the development of contralateral breast cancer and survival. Objectives: To establish whether women with hereditary breast cancer benefit from more extensive surgery than simple lumpectomy; to determine if oophorectomy influences overall mortality and incidence of contralateral tumours; and to establish if tamoxifen is useful in reducing second primary breast cancers. Work-to-date: We have enrolled 442 subjects in this study, and are continuing to collect medical records and complete follow-up on the remaining eligible cases. A crude univariate analysis suggests that improved survival is associated with diagnosis over 40, bilateral mastectomy, oophorectomy, chemotherapy, and tamoxifen. However, this preliminary analysis has not been adjusted for covariates or for variable length of follow-up.