Proximal Location as a Predictor of Metachronous Colorectal Cancer After Excision of Adenomas.

INTRODUCTION

To compare metachronous colorectal cancer (CRC) and advanced adenoma (AA) risk in patients with proximal vs. distal adenomas.

METHODS

We searched Pubmed, Embase, and Cochrane for cohort studies and clinical trials. Proximal adenomas were those located proximal to the descending colon. Pooled incidence rate ratios and 95% confidence intervals (CI) for CRC and AA were calculated using a random-effects model.

RESULTS

Compared with patients with only distal adenomas, patients with any proximal adenoma had a higher risk of metachronous CRC (1.70, 95% CI 1.17-2.45), proximal CRC (3.65, 95% CI 1.57-8.46), and AA (1.82, 95% CI 1.41-2.34).

DISCUSSION: Baseline adenoma proximal location is associated with future detection of CRC and AA.