Contralateral Prophylactic Mastectomy for Women with T4 Locally Advanced Breast Cancer

The use of contralateral prophylactic mastectomy (CPM) for women with unilateral breast cancer is increasing. The authors were interested in assessing whether this trend extended to patients with T4 disease.

We identified 92 patients from our prospective breast surgery registry with unilateral clinical T4 M0 disease who underwent mastectomy at our institution from October 2008 to July 2015. Patient, tumor, and treatment variables were compared between patients who did and those who did not undergo CPM, and the reasons patients elected CPM were ascertained.

Of the 92 patients, 33 (36 %) underwent a CPM, including 25 of 55 patients (45 %) with inflammatory breast cancer. Immediate breast reconstruction was performed for 11 of the 92 patients (12 %), including 4 CPM patients. Pathology showed benign findings in all 33 CPM cases, including 3 patients with atypical hyperplasia. The primary reason for CPM reported by the patients included fear of occult current or future breast cancer in 12 cases (36 %), symmetry in 11 cases (33 %), avoidance of future chemotherapy in 5 cases (15 %), deleterious BRCA mutation in 2 cases (6 %), contralateral benign breast disease in 2 cases (6 %), and medical oncologist recommendation in 1 cases (3 %). Patients selecting CPM were younger and more likely to have undergone BRCA testing.

A substantial rate of CPM was observed among women undergoing mastectomy for unilateral T4 breast cancer despite the considerable risk of mortality from their index cancer. The reasons for selection of CPM paralleled those reported for patients with early-stage disease. The most common motivation was fear of occult current or future breast cancer and included the desire to avoid further chemotherapy.