PD02-01: Impact of Contralateral Prophylactic Mastectomy on Surgical Outcomes.
Authors: Stover AC , Warren Peled A , Foster RD , Esserman LJ , Alvarado MD , Ewing CA , Hwang ES 
Published: June 2012

Abstract
Background: Among women with unilateral cancer, rates of contralateral prophylactic mastectomy (CPM) are continuing to increase. However, little is known about whether rates and types of complications differ between patients undergoing unilateral mastectomy or bilateral mastectomy, limiting the surgical outcomes evidence that can be presented in pre-surgical decision making for women considering CPM. This study was undertaken to determine whether surgical complications are increased in women undergoing CPM compared to those without CPM.
Methods: Between the years 2005–2010, all patients at UCSF undergoing mastectomy with immediate reconstruction were entered into a prospective database. This database was queried for patients with unilateral cancer who had mastectomy and immediate reconstruction with or without CPM. Surgical outcomes, including implant loss, admission for IV antibiotics, and return to OR were evaluated and compared between patients who did and did not undergo CPM. Patients with bilateral cancer or bilateral prophylactic surgery were excluded; analyses were limited to patients with a minimum of 1 year follow-up.
Results: 468 patients were identified who met study criteria, totaling 667 breasts. Mean follow-up time was 22 months (range 12 - 69 months). 269 of the 468 (57.5%) patients had unilateral mastectomy only, while 199 of 468 (42.5%) patients also had CPM. There were no differences in tumor grade, stage, follow-up time, smoking history, or radiation (prior or post-surgery) between the two groups. The only significant differences between the unilateral and bilateral groups were median age at diagnosis (50.7 vs. 45.9 respectively; p &lt; .0001) and receipt of neoadjuvant chemotherapy (34.7% vs. 41.3% respectively; p &lt; .01). Surgical outcomes were compared between groups. The overall rate of major complications differed significantly due to an increased rate of infectious complications and unplanned return to surgery in the CPM group (Table 1). Nevertheless, this did not result in a higher implant loss rate in the CPM group.

In patients undergoing bilateral mastectomy, overall complication rates were comparable between the index breast and the CPM breast; however, there was a higher implant loss rate in the index breast (22/177 vs. 11/188; p=0.05).
Conclusions: While CPM is an increasingly common procedure, it is associated with an increased risk of major post-operative surgical complications. In this cohort, patients undergoing bilateral mastectomy for unilateral cancer had higher rates of overall complications, greater use of IV antibiotics, and more frequent return to the operating room. Since the majority of CPM cases are not at sufficiently high risk for a second breast cancer to meet clinical criteria for prophylactic surgery, guidelines and clinical recommendations should consider these increased complication rates when counseling women contemplating CPM.
Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr PD02-01.