Su1353 Longstanding Chronic Granulomatous Disease Colitis Does Not Increase the Risk of Colorectal Cancer

Abstract

Introduction: Chronic granulomatous disease (CGD) is an immunodeficiency syndrome caused by a defective NADPH oxidase complex. Afflicted patients are unable to produce adequate reactive oxygen metabolites to neutralize microorganisms within macrophages. Approximately 50% of CGD patients develop gastrointestinal (GI) disease that shares features of both Crohn's disease and ulcerative colitis. In patients with pediatric-onset ulcerative colitis, the cumulative risk for colorectal cancer (CRC) is 2% at 10 years (yrs) and 8% at 20 yrs. While the increased risk of CRC among patients with longstanding inflammatory bowel disease (IBD) is well established, the incidence of CRC among CGD patients with longstanding colitis has not been described. Methods: Patients with CGD colitis were identified from a database comprised of 279 CGD patients seen at the NIH from 1972 to 2011. To allow for adequate endoscopic, pathologic, and clinical follow-up, 78 patients with evidence of CGD colitis seen between 1990 and 2010 were identified, and patients with disease duration >10 yrs were used for formal analysis. The clinical and endoscopic reports over the 10 year follow-up period were reviewed, and the colonic biopsies were reexamined when available. Demographic information, duration of disease, endoscopic findings, and treatment and surgical history were extracted from the electronic medical records. The primary endpoint was the evidence of dysplasia or development of CRC. Results: Of the 78 patients, 20 had disease for >10 yrs. Notably, no colonic dysplasia or CRC were seen at the time of the biopsies in any of these patients. Of the 20 patients with disease > 10 yrs, 8 had biopsies available for formal reexamination. On reexamination, no patients were found to have colonic dysplasia or CRC. For all 20 patients, the average age at diagnosis was 10 years, with the median duration of disease of 16.7 yrs. Polyps were noted in 5 of 20 patients, 3 of which were inflammatory, 1 hyperplastic and 1 normal mucosa. No patients were diagnosed with colorectal cancer during follow-up. Conclusions: Despite long-standing inflammation, there was no dysplasia or CRC among 20 patients with CGD after a median of 16.7 years of follow up. In addition, no cases of colonic dysplasia or CRC were found in any patients with CGD colitis. The incidence of CRC among patients with CGD colitis appears to be lower than the incidence among patients with IBD. In fact, there are no reported cases of malignant polyps, dysplasia, or any gastrointestinal cancers in the short term or long term data. Although limited by a retrospective study design, these data suggest that the development of CRC in the setting of chronic inflammation may be influenced by NADPH activity, suggesting superoxide metabolism as a possible target to prevent oncogenesis.