Risk factors for high-grade dysplasia or carcinoma in colorectal adenoma cases treated with endoscopic polypectomy

OBJECTIVE: Our aim is to establish the risk factors for carrying high-grade dysplasia or carcinoma by analyzing endoscopically treated adenoma cases. METHODS: Patients who underwent endoscopic polypectomy at our hospitals between January 2003 and August 2004 were analyzed. RESULTS: A total of 889 patients (mean age: 63±11 years), and 1486 adenomas resected from these patients, were included in the analysis. Seventy-five adenomas (5%) from 72 patients (8%) were found to have high-grade dysplasia or carcinoma. Among patient factors, female sex [odds ratio (OR) 2.25, 95% confidence intervals (CI)=1.34-3.76], presence of multiple adenomas (OR=2.15, 95% CI=1.15-4.00), older age (OR=1.02, 95% CI=1.00-1.04), and rectal bleeding as the indication for colonoscopy (OR=2.57, 95% CI=1.34-4.92) were identified as the significant risk factors for carrying high-grade dysplasia or carcinoma using the multivariate analysis. In addition, a size of ≥10 mm (OR=10.83, 95% CI=5.86-20.0), flat appearance (OR=3.91, 95% CI=2.20-6.95), and location on the left side of the colon (OR=1.80, 95% CI=1.03-3.13) were identified as tumor risk factors. CONCLUSION: Distinct factors were proved to be associated with high-grade dysplasia or carcinoma. These results are useful to select lesions that require immediate treatment. Moreover, female sex as a risk factor raises an interesting problem regarding the progression from adenoma to carcinoma.