Body Mass Index Does Not Affect Postoperative Morbidity and Oncologic Outcomes of Total Mesorectal Excision for Rectal Adenocarcinoma

Introduction: Obesity adds to the technical difficulty of colorectal surgery and is a risk factor for postoperative complications. We hypothesized that obese patients have increased morbidity and poor oncologic outcomes after proctectomy for rectal adenocarcinoma.

Methods: Adult patients undergoing total mesorectal excision (TME) for rectal adenocarcinoma at a tertiary referral center were retrospectively identified from a prospectively maintained database. Operative characteristics, postoperative complication rates, and oncologic outcomes were compared in patients with BMI > or = 30 kg/m(2) and BMI < 30 kg/m(2).

Results: Between 1997 and 2009, 254 patients underwent proctectomy for rectal adenocarcinoma, of whom 27% were obese. There were no significant differences in demographics, comorbidities or preoperative oncologic characteristics between obese and nonobese groups. Patients with BMI > or = 30 kg/m(2) had longer operative times (p = 0.04) and higher intraoperative blood loss (p < 0.001) but comparable postoperative complication rates (p = 0.80), number of lymph nodes retrieved (p = 0.57), margin-negative resections (p = 0.44), and disease-free survival (p = 0.11). Obese patients had longer overall survival (p = 0.05). Tumor stage was the only variable associated with disease-free (p < 0.001) and overall survival (p < 0.001).

Conclusion: Despite increased technical difficulty of resection, obesity does not increase the risk of postoperative morbidity or adversely affect oncologic outcomes after total mesorectal excision of rectal adenocarcinoma.