Background: The increasing trend of women with unilateral breast cancer to electively undergo contralateral prophylactic mastectomy in addition to treatment of the index breast has been controversial. The authors set out to better frame the risks and benefits of contralateral prophylactic mastectomy in the treatment of unilateral breast cancer by evaluating outcomes of a large, consecutive cohort of patients.
Methods: An institutional review board-approved review of a single-surgeon (N.T.) experience (2013 to 2018) was conducted of all consecutive patients with unilateral breast cancer treated with mastectomy and immediate reconstruction. Patient characteristics, surgical pathologic results, and 30-day complications were assessed. Outcomes of patients with unilateral cancer who underwent unilateral mastectomy versus bilateral mastectomy (with one breast being contralateral prophylactic mastectomy) were compared. Logistic regression models evaluated various risk factors for potential associations with positive pathologic findings in the contralateral prophylactic mastectomy specimen and/or postoperative complications.
Results: Of 244 patients, 68 (27.9 percent) underwent unilateral mastectomy and 176 (72.1 percent) underwent contralateral prophylactic mastectomy. Surgical pathologic results of the prophylactic breast revealed occult ductal carcinoma in situ or invasive cancer in 13 patients (7.3 percent) and lobular carcinoma in situ in eight patients (4.6 percent). Incidence of complications was similar between groups [unilateral mastectomy, 19.12 percent (n = 13); contralateral prophylactic mastectomy, 13.07 percent (n = 23); p = 0.234].
Conclusions: Immediate reconstruction for unilateral mastectomy and contralateral prophylactic mastectomy have similar complication risk profiles, among patients as a whole and between individual breasts. These findings contribute to our understanding of the clinical impact prophylactic mastectomy and reconstruction may have on optimizing the counseling among extirpative surgeons, reconstructive surgeons, and patients.
Clinical question/level of evidence: Therapeutic, III.