Survival Outcome of Local Excision versus Radical Resection of Colon or Rectal Carcinoma A Surveillance, Epidemiology, and End Results (SEER) Population-Based Study

Objective: To compare cancer-specific results of local excision with major resection. Background: Technological advances have enabled endoscopic and local excision techniques to be applied in the treatment of early colorectal cancer in preference to radical surgery. Method: Patients with stage 0 (carcinoma in situ) or stage I (T1/2N0M0) adenocarcinoma of the colon or rectum undergoing surgery between 1998 and 2009 were included from the SEER (Surveillance, Epidemiology, and End Results) database. Local excision (endoscopic or surgical) was compared with major surgical resection using adjusted hazard ratios (HRs) for 5-year cancer-specific survival (CSS). Results: This study included 7378 local excisions and 36,116 major resections. There were 3553 patients with carcinoma in situ and 39,941 with clinical stage I cancer. Local tumor excision for carcinoma in situ was associated with equivalent CSS compared to major resection (HRs = 1.06, P = 0.814, for colon and 0.78, P = 0.494, for rectum). Local excision of T1 and T2 colon cancer was associated with reduced CSS (HR = 1.31, P = 0.020, and 2.89, P < 0.001, respectively). Local excision of T1 rectal cancer did not affect CSS (HR = 1.16, P = 0.236), but it significantly reduced CSS for T2 cancer (HR = 1.71, P < 0.001). Subgroup analysis of T1 and T2 rectal cancer after neoadjuvant therapy and local excision showed oncological equivalence to major resection (HR = 1.12, P = 0.802, and 1.23, P = 0.802). Conclusions: Local excision for early colorectal cancer was oncologically equivalent to major surgery for carcinoma in situ and T1 rectal cancer, but inferior for T1-2 colon and T2 rectal cancer. Exploratory data suggest local excision of T1-2 rectal cancer after neoadjuvant therapy may be safe.