Endoscopic versus surgical resection for early colorectal cancer-a systematic review and meta-analysis

Background: To investigate the available data on the treatment of early colorectal cancer (CRC), either endoscopically or surgically.

Methods: Two independent reviewers searched MEDLINE, EMBASE, CENTRAL COCHRANE, LILACS and EBSCO for articles published up to August 2015. No language or dates filters were applied. Inclusion criteria were studies with published data about patients with early colonic or rectal cancer undergoing either endoscopic resection (i.e., mucosectomy or submucosal dissection) or surgical resection (i.e., open or laparoscopic). Extracted data items undergoing meta-analysis were en bloc resection rate, curative resection rate, and complications. A complementary analysis was performed on procedure time. The risk of bias among studies was evaluated with funnel-plot expressions, and sensitivity analyses were carried out whenever a high heterogeneity was found. The risk of bias within studies was assessed with the Newcastle score.

Results: A total of 12,819 articles were identified in the preliminary search. After applying inclusion and exclusion criteria, three cohort studies with a total of 768 patients undergoing endoscopic resection and 552 patients undergoing surgical resection were included. The en bloc resection rate risk difference was -11% [-13%, -8% confidence interval (CI)], demonstrating worse outcome results for the endoscopic resection group as compared to the surgical resection group [number need to harm (NNH) =10]. The curative resection rate risk difference was -9% [(-12%, 6% CI)] after a sensitivity analysis was performed, which also demonstrated worse outcomes in the intervention group (NNH =12). The complications rate exhibited a -7% risk difference [(-11%, -4% CI)], denoting a lesser number of complications in the endoscopic group [Number Need to Treat (NNT =15). A complementary analysis of procedure time with two of the selected studies demonstrated a mean difference of -118.32 min [(-127.77, -108.87 CI)], in favor of endoscopic resection, even though such data lacks homogeneity across studies, and could be heavily influenced by local expertise. Long-term results were found in only one study and therefore were not included in the final analysis.

Conclusions: According to the current available data, the treatment of early CRC by surgical resection is associated with higher curative resection rates and higher en bloc resection rates, despite of higher complications rates, as compared to endoscopic resection. Shorter procedure times are associated with the endoscopic methods of treatment, however high heterogeneity levels limit this conclusion.