Management and outcomes of anorectal infection in the cancer patient

Background. The objective of this retrospective cohort study is to examine the presentation and outcomes for a contemporary series of cancer patients with anorectal infection. In addition, we seek to identify factors which are associated with surgical intervention. Methods. The study cohort was identified from International Classification of Disease (ICD)-9 codes for diagnosis of infection of the anal and rectal region and patients who underwent a surgical oncology consultation at The University of Texas M.D. Anderson Cancer Center between 1/2000 and 12/2006. Clinical presentation, treatment rendered, and outcomes were retrospectively recorded. Results. Of the 100 patients evaluated by the surgical oncology service for anorectal infection, 42 were treated nonoperatively and 58 underwent surgical intervention. Factors associated with surgical intervention based on logistic multivariable analysis included diagnosis of an abscess [odds ratio (OR) 10.5, 95% confidence interval (CI) 2.9-38.5] and documentation of erythema on physical examination (OR 3.1, 95% CI 1.1-8.4). Thrombocytopenia (platelets <50,000) was associated with nonoperative management (OR 0.3, 95% CI 0.1-0.7). Incision and drainage was the most common surgical procedure (79%) while a wide debridement for a necrotizing soft tissue infection was required in two patients. Infection-specific 90-day mortality was 1% (n = 1), attributable to a necrotizing infection. However, median overall survival for the entire cohort was only 14.4 months (95% CI 7.9- 19.5 months). Conclusions. Identification of an abscess, erythema on physical exam, and thrombocytopenia were associated with management strategy. Although rare, necrotizing soft tissue infections are associated with significant mortality.