A Pooled Analysis of Advanced Colorectal Neoplasia Diagnoses After Colonoscopic Polypectomy

Received 8 August 2008; accepted 1 December 2008. published online 10 December 2008.

Background & Aims

Limited data exist regarding the actual risk of developing advanced adenomas and cancer after polypectomy or the factors that determine risk.

Methods

We pooled individual data from 8 prospective studies comprising 9167 men and women aged 22 to 80 with previously resected colorectal adenomas to quantify their risk of developing subsequent advanced adenoma or cancer as well as identify factors associated with the development of advanced colorectal neoplasms during surveillance.

Results

During a median follow-up period of 47.2 months, advanced colorectal neoplasia was diagnosed in 1082 (11.8%) of the patients, 58 of whom (0.6%) had invasive cancer. Risk of a metachronous advanced adenoma was higher among patients with 5 or more baseline adenomas (24.1%; standard error, 2.2) and those with an adenoma 20 mm in size or greater (19.3%; standard error, 1.5). Risk factor patterns were similar for advanced adenomas and invasive cancer. In multivariate analyses, older age (P < .0001 for trend) and male sex (odds ratio [OR], 1.40; 95% confidence interval [CI], 1.19–1.65) were associated significantly with an increased risk for metachronous advanced neoplasia, as were the number and size of prior adenomas (P < .0001 for trend), the presence of villous features (OR, 1.28; 95% CI, 1.07–1.52), and proximal location (OR, 1.68; 95% CI, 1.43–1.98). High-grade dysplasia was not associated independently with metachronous advanced neoplasia after adjustment for other adenoma characteristics.

Conclusions

Occurrence of advanced colorectal neoplasia is common after polypectomy. Factors that are associated most strongly with risk of advanced neoplasia are patient age and the number and size of prior adenomas.

Abbreviations used in this paper: BMI, body mass index, CI, confidence interval, OR, odds ratio

⁎ Arizona Cancer Center, University of Arizona, Tucson, Arizona

‡ Mel and Enid Zuckerman Arizona College of Public Health, University of Arizona, Tucson, Arizona

‡‡‡ Department of Medicine, University of Arizona, Tucson, Arizona

§ Departments of Medicine and Community and Family Medicine, Dartmouth Medical School, Lebanon, New Hampshire

∥ Department of Veterans Affairs Medical Center, Portland, Oregon

¶ Nutritional Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Rockville, Maryland

# Center for Cancer Research, National Cancer Institute, National Institutes of Health, Rockville, Maryland

⁎⁎ Department of Gastroenterology and Nutrition Science, Memorial Sloan-Kettering Cancer Center, New York, New York

‡‡ Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, New York

§§ Department of Veterans Affairs Medical Center, Denver, Colorado

∥∥ Department of Medicine, Minneapolis Veterans Affairs Medical Center, Minneapolis, Minnesota

¶¶ Division of Environmental Health Sciences, University of Minnesota School of Public Health, Minneapolis, Minnesota

## Department of Veterans Affairs Medical Center, White River Junction, Vermont

⁎⁎⁎ Departments of Nutrition and Epidemiology, Harvard School of Public Health, Boston, Massachusetts

§§§ Cancer Prevention Program, Fred Hutchinson Cancer Research Center, Seattle, Washington

Reprint requests Address requests for reprints to: María Elena Martínez, PhD, University of Arizona, Arizona Cancer Center, PO Box 245024, Tucson, Arizona 85724. fax: (520) 626-9275

Conflicts of interest The authors disclose no conflicts.

Funding The authors disclose the following: this work was supported by Public Health Service grants CA-41108, CA-23074, CA95060, CA37287, CA104869, CA23108, CA59005, and CA26852 from the National Cancer Institute. Dr Jacobs is supported by a K07 Career Development Award (CA106269) from the National Cancer Institute. Funding for the Veteran's Affairs Study was supported by the Cooperative Studies Program, Department of Veterans Affairs.

PII: S0016-5085(08)02182-3

doi:10.1053/j.gastro.2008.12.007

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