Remove Second Breast to Prevent Cancer?
Study Probes First Breast Cancer and Decision to Get Preventive Mastectomy in Second Breast
Jan. 26, 2009 -- When a woman has a mastectomy to remove breast cancer in one breast, what should she do about the other breast?
Her first breast cancer may hold some clues, according to a new study, published in the advance online edition of Cancer.
"Not every woman who has breast cancer will get another breast cancer in the opposite breast," researcher Kelly Hunt, MD, tells WebMD.
"We tried to distill down some of those factors with our study and figure out which ones may be the most important ones," says Hunt, a professor of surgical oncology at the University of Texas M.D. Anderson Cancer Center.
But the findings don't amount to a checklist for getting a preventive mastectomy; breast cancer experts say that's still a personal decision that each patient must weigh with her doctors.
Hunt's study included 542 women who had a mastectomy at the M.D. Anderson Cancer Center to remove a cancerous breast, and also chose to get a precautionary mastectomy in the unaffected breast, a procedure called contralateral prophylactic mastectomy.
Immediately after the contralateral prophylactic mastectomy, tests showed that the vast majority of women -- about 95% -- had no cancer in that breast, and only 1.5% had an invasive tumor in that breast.
Because women typically get preventive mastectomies to curb their future risk, Hunt's team also followed another 1,574 women who had mastectomy to remove a cancerous breast but chose not to have a preventive mastectomy in their second breast. Over the next four years or so (50 months), only 2.4% of the women developed breast cancer in their remaining breast. It's not clear how many of those cancers were invasive tumors.
Hunt and colleagues found three factors that were more common among women with cancer in the breast that they had removed as a precaution. Those factors are:
- Having more than one tumor in the breast that was first diagnosed.
- Having invasive lobular cancer in the breast that was first diagnosed.
- Being at high risk for breast cancer, according to the Gail model.