Prevalence of nonpolypoid (flat and depressed) colorectal neoplasms in asymptomatic and symptomatic adults.

CONTEXT: Colorectal cancer is the second leading cause of cancer death in the United States. Prevention has focused on the detection and removal of polypoid neoplasms. Data are limited on the significance of nonpolypoid colorectal neoplasms (NP-CRNs). OBJECTIVES: To determine the prevalence of NP-CRNs in a veterans hospital population and to characterize their association with colorectal cancer. DESIGN, SETTING, AND PATIENTS: Cross-sectional study at a veterans hospital in California with 1819 patients undergoing elective colonoscopy from July 2003 to June 2004. MAIN OUTCOME MEASURES: Endoscopic appearance, location, size, histology, and depth of invasion of neoplasms. RESULTS: The overall prevalence of NP-CRNs was 9.35% (95% confidence interval [95% CI], 8.05%-10.78%; n = 170). The prevalence of NP-CRNs in the subpopulations for screening, surveillance, and symptoms was 5.84% (95% CI, 4.13%-8.00%; n = 36), 15.44% (95% CI, 12.76%-18.44%; n = 101), and 6.01% (95% CI, 4.17%-8.34%; n = 33), respectively. The overall prevalence of NP-CRNs with in situ or submucosal invasive carcinoma was 0.82% (95% CI, 0.46%-1.36%; n = 15); in the screening population, the prevalence was 0.32% (95% CI, 0.04%-1.17%; n = 2). Overall, NP-CRNs were more likely to contain carcinoma (odds ratio, 9.78; 95% CI, 3.93-24.4) than polypoid lesions, irrespective of the size. The positive size-adjusted association of NP-CRNs with in situ or submucosal invasive carcinoma was also observed in subpopulations for screening (odds ratio, 2.01; 95% CI, 0.27-15.3) and surveillance (odds ratio, 63.7; 95% CI, 9.41-431). The depressed type had the highest risk (33%). Nonpolypoid colorectal neoplasms containing carcinoma were smaller in diameter as compared with the polypoid ones (mean [SD] diameter, 15.9 [10.2] mm vs 19.2 [9.6] mm, respectively). The procedure times did not change appreciably as compared with historical controls. CONCLUSION: In this group of veteran patients, NP-CRNs were relatively common lesions diagnosed during routine colonoscopy and had a greater association with carcinoma compared with polypoid neoplasms, irrespective of size.

Short- and long-term outcomes of standardized EMR of nonpolypoid (flat and depressed) colorectal lesions > or = 1 cm (with video).

BACKGROUND: Nonpolypoid (flat and depressed) colorectal lesions are increasingly recognized. Their endoscopic removal requires specialized EMR techniques, which are more complex to perform. Outcomes data on EMR of nonpolypoid neoplasms in the United States is needed. OBJECTIVE: To determine the safety and efficacy of EMR in the resection of nonpolypoid colorectal neoplasms > or = 1 cm. DESIGN: Retrospective analysis. SETTING: Veterans Affairs Palo Alto Health Care System. PATIENTS: Over a 5-year period, patients who underwent EMR for nonpolypoid colorectal lesions > or = 1 cm. INTERVENTION: A standardized approach that included lesion assessment, classification, inject-and-cut EMR technique, reassessment, and treatment of residual tissue. MAIN OUTCOME MEASUREMENTS: Complete resection, bleeding, perforation, development of advanced cancer, and death. RESULTS: A total of 100 patients (125 lesions: 117 flat and 8 depressed) met inclusion criteria. Mean size was 16.7 +/- 7 mm (range, 10-50 mm). Histology included 5 submucosal invasive cancers, 5 carcinomas in situ, and 91 adenomas. Thirty-eight patients (48 lesions) did not receive surveillance colonoscopy: 8 had surgery, 16 had hyperplastic pathology, and 14 did not undergo repeat examination. Surveillance colonoscopy was performed on 62 patients (77 lesions). Complete resection was achieved in 100% of these patients after 1 to 3 surveillance colonoscopies. All patients received follow-up (mean [standard deviation] = 4.5 +/- 1.4 years); none developed colorectal cancer or metastasis. LIMITATIONS: Single endoscopist, retrospective study. CONCLUSIONS: A standardized EMR (inject-and-cut) technique is a safe and curative treatment option in nonpolypoid colorectal neoplasms (> or = 1 cm) in the United States.