Abstract P4-17-01: The effect of body mass index on breast reconstruction outcomes.
Authors: Lopez JJ , Laronga C , Doren EL , Sun W , Fulp WJ , Smith PD 
Published: August 2014

Abstract
Introduction: With increasing numbers of women choosing mastectomy for breast cancer treatment, breast reconstruction is consequentially on the rise. Obesity, a known predictor for wound healing complications, is also on the rise. Our objective is to review our institutional experience with the association between Body Mass Index (BMI) and breast reconstruction complications.
Methods: An IRB approved retrospective review of prospectively gathered patients having mastectomy with reconstruction was conducted. Data including patient demographics, stage at diagnosis, adjuvant treatment, type of mastectomy, type of reconstruction, and complications were collected. Patients were stratified by BMI into two categories: Normal weight (BMI 18.5–24.9), and overweight/obese (BMI 25 or greater). The statistical analysis was preformed using Wilcoxon Rank-Sum Test and Chi Squared Test, both using exact method with Monte Carlo estimation.
Results: From 06/1996 to 08/2011, 443 patients were identified having mastectomy and reconstruction. Of these, 218 patients had a normal weight at the time of mastectomy; 225 patients were overweight/obese. The overall median age was 49 years (range: 18–82). 780 mastectomies with reconstruction (106 unilateral, 337 bilateral) were performed. The most common reconstruction types included 477 tissue expander with implant reconstructions (62.8% of breasts), 106 latissimus flap with prosthesis (14.0%), and 103 pedicled TRAM flaps (13.6%). 245 patients (55.3%) experienced at least one complication; the most common complications were fat necrosis (80 patients, 18.1% of patients), infection (57, 12.9%), epidermolysis (41, 9.3%), and skin necrosis (39, 8.8%).
The overweight/obese group had a significantly higher prevalence of diabetes (6.3% vs. 0.9%, p = 0.0036) and hypertension (26.7% vs. 11.1%, p &lt; 0.0001) and was more likely to receive neoadjuvant chemotherapy (16.2% vs. 4.8% p = 0.0005), possibly due to presentation at a later stage, but no significant differences were identified. Other comorbid conditions, including smoking, history of breast cancer, adjuvant chemotherapy, and history of or postsurgical radiation, were similar between the two groups. One significant difference was that the overweight/obese group was significantly older than the normal weight group (p = 0.0005).
There were no significant differences identified in the incidence of any individual complication between the two BMI groups. Additionally, the incidence of a patient having any complication was similar between the two groups (128 overweight/obese patients for 56.9% and 117 normal weight patients for 53.7%, p = 0.4918). When using breasts instead of patients as the unit of measure, when an overweight/obese patient had a complication they were significantly more likely to require an unanticipated return to the OR (93/160 breasts with a complication for 58.1% vs. 67/154 for 43.5%, p = 0.0124).
Conclusion: Obesity does not increase the risk of breast reconstruction complications, but increases the severity of complications if one should arise. This supports the continued use of breast reconstruction in patients regardless of their weight, and emphasizes that when the correct procedure is selected for an overweight/obese patient, outcomes can be similar to patients that are of a normal weight.
Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P4-17-01.