Anal canal squamous cell cancer: are surgical alternatives to chemoradiation just as effective?

Abstract

The purpose of this paper is to study long-term oncologic outcomes after different treatment strategies for anal canal cancer (SCAC). Patients with SCAC (2004-2013) were identified from Surveillance, Epidemiology, and End Results (SEER) database. Patients undergoing radiation (RT) were compared to those undergoing local excision (LE), abdominoperineal resection (APR), and abdominoperineal resection after radiation (RT + APR). Overall survival (OS) and cancer-specific survival (CSS) data were evaluated using Kaplan-Meier and Cox regression. Two thousand seven hundred and seventy-two (83.8%) patients underwent RT, 382 (11.6%) LE, 77 (2.3%) APR, 76 (2.3%) RT + APR. Median age for the four groups was 60, 57, 64, and 56years and 32, 49.7, 53.2, and 39.5% were male, respectively, while median tumor size was 4.4, 2.6, 5.3, and 5.5cm, respectively. Five-year OS of RT, LE, APR, and RT + APR groups was 63.7, 79.6, 25.8, and 41.8% while CSS was 79.6, 92.5, 75.6, and 58.8%, respectively, (p < 0.001). Adjusted hazard ratios for OS for LE, APR, and RT + APR with RT as reference were 1.007 (0.702-1.444), 2.311 (1.367-3.906), and 2.072 (1.016-4.228), respectively. These data suggest that APR does not provide better outcomes in treatment of SCAC. Chemoradiation remains the gold standard treatment for majority of patients. Local excision is associated with favorable outcomes in some circumstances.