Women with BRCA1 and BRCA2 mutations survive ovarian cancer at higher rates than those without mutations
Results from a National Cancer Institute (NCI) sponsored multicenter study published in the Journal of the American Medical Association on January 25, 2012, provides strong evidence that BRCA1 and BRCA2 gene mutation carriers with ovarian cancer were more likely to survive in the five years following diagnosis than were women with ovarian cancer who do not have mutations in these genes. These findings expand on a 2011 abstract presentation of the results and also offer a contrast with a recent analysis of data from The Cancer Genome Atlas (TCGA) project, which reported an improved prognosis for only BRCA2 carriers. This new, larger study also found an improved prognosis for BRCA1 carriers, whereas the smaller TCGA data set suggested no difference between BRCA1 carriers and non-carriers.
It is well known that rare mutations in the genes BRCA1 and BRCA2 confer high risks of both breast and ovarian cancer. While previous work suggested that ovarian cancer patients with a BRCA mutation have better survival than patients without these mutations, those studies were limited by small numbers and were not able to look at BRCA1 and BRCA2 mutations independently. In this study, NCI scientists further investigated the relationship between specific BRCA mutations and ovarian cancer survival. The investigators examined 1,213 cases of epithelial ovarian cancer, including 909 women with BRCA1 mutations, 304 with BRCA2 mutations, and 2,666 without mutations. They found that the BRCA2 mutation carriers had greater survival than BRCA1 mutation carriers. BRCA2 carriers showed a 52 percent survival rate at five years following diagnosis, while BRCA1 carriers showed a 44 percent survival rate. Women without the gene mutations had a survival rate of 36 percent. Previous work has suggested that the survival advantage of BRCA1 and BRCA2 mutation carriers may be due to a better response to platinum-based chemotherapy.