Study: Ovary Removal May Cut Breast Cancer Risk in Women With Genetic Defect

Women with a genetic defect that makes them more likely to get breast cancer may lower their risk by 75 percent if they have surgery to remove their ovaries and fallopian tubes, according to researchers.

A mutation in the genes, called BRCA1 and BRCA2, has been found to significantly increase the risk of both breast and ovarian cancer. Many women with this genetic defect currently opt to preemptively have their breasts removed to reduce their risk of cancer.

But researchers told the American Society of Clinical Oncology annual meeting that women who have their ovaries and fallopian tubes removed, and then take tamoxifen, may bring their risk down to the normal level without having a preemptive mastectomy.

"We now have prospective evidence to present to patients so that they can make informed decisions about their care," said Dr. Kenneth Offitt of Memorial Sloan-Kettering Cancer Center.

Women with the BRCA genes -- which tend to occur disproportionately in Jewish women of Eastern European origin -- are estimated to have between a 50 percent and 85 percent lifetime risk of breast cancer and between a 10 percent and 40 percent risk of ovarian cancer.

But Offit said that in a study of these women with BRCA mutations at Memorial Sloan Kettering:

• 98 women had their ovaries and fallopian tubes removed, and during a follow-up period that averaged nearly two years, 3 were diagnosed with breast cancer and one with peritoneal cancer.
• 72 women chose to not have the preemptive surgery, and during the same followup period, 8 breast cancers, 3 ovarian cancers, 1 fallopian tube cancer and 1 peritoneal cancer were diagnosed.

"This is a highly significant difference," said Offitt. "And the surgery can be performed by laparoscopy and it is safe."

Offitt and Dr. Olufunmilayo Olopade of the University of Chicago both emphasized that the decision to have ovaries and fallopian tubes removed need not interfer with a woman's desire to have a family. since the risk of these cancers increases markedly after age 35 to 40.

"You can actually wait until after a woman has completed having a family before this (surgical) intervention," Olopade said.

Other sources: ASCO