BRCA type sways benefit of anti-cancer surgery
By Anthony J. Brown, MD
NEW YORK (Reuters Health) - Women with BRCA1 and BRCA2 gene mutations can lower their risk of developing breast and gynecologic cancers by having their ovaries removed. However, the benefit depends on which mutation they have, researchers have found.
Ovary removal significantly reduces the odds of gynecologic cancer in BRCA1 carriers and the risk of breast cancer in BRCA2 carriers, Dr. Noah D. Kauff, from Memorial Sloan-Kettering Cancer Center in New York, and his associates report.
"All previous studies have either combined BRCA1 and BRCA2 mutation carriers together or evaluated BRCA1 mutation carriers alone," Kauff explained to Reuters Health. "As many as 39 percent of all BRCA mutation carriers have a mutation in BRCA2 and these women may have very different responses to risk-reducing interventions than women with BRCA1 mutations."
The most important finding of the study, he said, "is that carriers of BRCA2 mutations appear to receive substantially greater protection against breast cancer from (ovary removal) than carriers of BRCA1 mutations. As this issue has never been evaluated before, this is new information and surprising."
The study, reported in the Journal of Clinical Oncology, involved more than 1000 women with a BRCA1 or BRCA2 mutation, who made the decision to undergo ovary surgery or to just have regular cancer check-ups.
Compared to the women who did not have surgery, those who underwent removal of their ovaries were 85 percent less likely to develop BRCA1-associated gynecologic cancers over a 3-year period, and 72 percent less likely to develop BRCA2-associated breast cancer.
The surgery also reduced risks of BRCA2-associated gynecologic cancer and BRCA1-associated breast cancer, but these results were not significant from a statistical standpoint.
"These findings should help women with BRCA mutations and their doctors make more informed choices about strategies to reduce their risk of breast and gynecologic cancers," Kauff said.
SOURCE: Journal of Clinical Oncology, online February 11, 2008.