Trends, patterns, and outcomes in the management of malignant colonic polyps in the general population of the United States

BACKGROUND: Colonoscopic screening has increased detection of malignant colonic polyps (MPs). The goal of this study was to analyze trends and patterns in the surgical treatment of MPs and to assess outcomes as measured by lymph node retrieval and patient survival. METHODS: The Surveillance, Epidemiology, and End Results (SEER) registry was queried to identify 19,743 patients with MPs from 1988 to 2003. RESULTS: The majority of MPs were present in the sigmoid and descending colon (54%), and 38% were tubular, 40% were tubulovillous, and 22% were villous. During the study period, the incidence of MPs increased from 29% to 42% and surgical resection (SR) was increasingly used for treatment, from 54% to 70%. Predictors of SR were aged <70 years (odds ratio [OR], 1.3; 95% confidence interval [95% CI], 1.2-1.4), high-grade tumors (OR, 1.5; 95% CI, 1.2-1.9), diagnosis in 1999 through 2003 (OR, 1.7; 95% CI, 1.5-1.9), villous subtype (OR, 2.3; 95% CI, 2.0-2.6), and right colon location (OR, 8.1; 95% CI, 7.0-9.4). In patients undergoing SR, the mean and median number of lymph nodes was only 4 and 1, respectively. A significant percentage of patients (49%) had no lymph nodes retrieved and a worse overall survival at 5 years compared with patients who had at least 1 lymph node examined (64% vs 74%; P <.001). CONCLUSIONS: MPs appear to be increasing in incidence, and there is a trend toward increased use of SR for treatment. However, patients undergoing SR for MPs undergo suboptimal assessment of lymph nodes, with a detrimental impact on survival. Adequate lymphadenectomy and lymph node evaluation are crucial to improve outcomes in patients with these potentially curable lesions.