In Asians, Many Polyps <10 mm Have Advanced Histology
Researchers say those with polyps larger than 5 mm should be offered colonoscopy, polypectomy
MONDAY, Jan. 31 (HealthDay News) -- Many polyps smaller than 10 mm in Asian patients have advanced histologic features, so Asian patients with polyps larger than 5 mm should be referred for colonoscopy and polypectomy rather than computed tomography colonography (CTC) surveillance, according to a study published in the January issue of Clinical Gastroenterology and Hepatology.
Joseph J.Y. Sung, M.D., Ph.D., from the Chinese University of Hong Kong in Shatin, and colleagues analyzed data from 1,457 subjects participating in colorectal cancer screening programs. Polyps and advanced colonic neoplasia (ACN) identified during colonoscopic examinations were classified according to size and histology.
Of the patients screened, the researchers found that 38.2 percent had polyps; 16.7 percent of these were ACN, of which 5.4 percent were ≤5 mm and 24.7 percent were 6 to 9 mm. The usual practice of treating polyps smaller than 5 mm as normal and repeating CTC for polyps of 6 to 9 mm would result in misclassification of 5.4 percent of ACN as normal, and would delay polypectomies in 20.4 percent of those with ACN. The authors conclude that, because a substantial proportion of polyps smaller than 10 mm in Asian patients have advanced histologic features, those whose polyps are 6 mm or larger should be referred for colonoscopy and polypectomy instead of CTC surveillance.
"This is consistent with the new Joint Guideline from the American Cancer Society, the U.S. Multi-Society Task Force on Colorectal Cancer, and the American College of Radiology," the authors write.