Predictors of contralateral breast cancer identified

February 15, 2009

In unilateral breast cancer patients, evaluating 5-year Gail risk and histologic findings in the ipsilateral breast may predict the risk of developing cancer in the other breast and help clinicians decide whether to perform a contralateral prophylactic mastectomy.

In unilateral breast cancer patients, evaluating 5-year Gail risk and histologic findings in the ipsilateral breast may predict the risk of developing cancer in the other breast and help clinicians decide whether or not to perform a contralateral prophylactic mastectomy, according to an article published online Jan. 26 in Cancer.

Min Yi, MD, of the University of Texas M.D. Anderson Cancer Center in Houston, and colleagues studied 542 unilateral breast cancer patients who underwent contralateral prophylactic mastectomy between January 2000 and April 2007.

The investigators found that 25 of the patients (5%) had an occult malignancy in the contralateral breast and that 82 patients (15%) had moderate- to high-risk histologic findings in the contralateral breast. Predictors of malignancy in the contralateral breast included an ipsilateral invasive lobular histology, an ipsilateral multicentric tumor, and a 5-year Gail risk of at least 1.67%, while predictors of moderate- to high-risk histologic findings in the contralateral breast included an age of at least 50 years at diagnosis in addition to ipsilateral moderate-risk to high-risk pathology, the researchers report.

"Contralateral prophylactic mastectomy may be a rational choice for breast cancer patients who have a five-year Gail risk greater than or equal to 1.67%, an additional ipsilateral moderate-risk to high-risk pathology, an ipsilateral multicentric tumor, or an ipsilateral tumor of invasive lobular histology," the authors conclude.

Yi M, Meric-Bernstam F, Middleton LP, et al. Predictors of contralateral breast cancer in patients with unilateral breast cancer undergoing contralateral prophylactic mastectomy. Cancer. 2009; DOI 10.1002/cncr.24129.