Radical Treatment Not Best Course for BRCA Mutations

Annette Heemskerk-Gerritsen, a PhD student in the Department of Medical Oncology, Erasmus Medical Centre, Rotterdam, the Netherlands, described a study that looked at the efficacy of risk-reducing mastectomy (RRM) in 390 patients with the BRCA1/2 genetic mutation who already had cancer in 1 breast. One hundred thirty-eight underwent RRM and the balance continued with regular surveillance; there were no observed differences in age at diagnosis, hormone-receptor status, and adjuvant systemic treatment between the 2 groups. There were greater numbers of patients undergoing adjuvant chemotherapy and risk-reducing salpingo-oophorectomy in the RRM group.

The regular surveillance group experienced 54 patients who developed metastatic disease during 2033 person-years of observation (PYO), as opposed to 18 patients during 642 PYO in the RRM group. Regarding overall survival, 56 women in the non-RRM group died (in 2164 PYO), and 16 in the RRM group (in 682 PYO).

According to background information provided in the press release announcing these findings, women who carry the mutated BRCA1/2 gene have a risk of between 55% and 85% of developing cancer in their lifetime, and those who do develop it have to make difficult decisions about their treatment, often opting for the most radical therapy in the belief that they will have a better chance of overcoming their disease. Until now there has been little data on the longer-term effects of such treatments on these patients.

“RRM obviously reduces the incidence of breast cancer in the other breast to zero,” said Ms Heemskerk-Gerritsen, but “we found that there was very little difference in disease-free and overall survival between the 2 groups.”

As to next steps and how this information might eventually be used in patient care, Ms Heemskerk-Gerritsen remarked, “We intend to follow up this study by identifying a set of prognostic factors related to survival in breast cancer patients with a BRCA1 or BRCA2 mutation. In this way, we hope to be able to identify a subgroup of patients who may benefit from RRM. In the meantime, we hope that our findings will provide additional information to improve the counseling of breast cancer patients considering risk-reducing mastectomy, by emphasizing that the gain that may be obtained by this radical surgery is mainly in respect of reducing the risk of contralateral breast cancer.”