-Original-

Total Colonoscopy Detects Early Colorectal Cancer More Frequently than Advanced Colorectal Cancer in Patients with Fecal Occult Blood

Takuji Ozaki^1,2, Akira Tokunaga^1,2, Naoto Chihara^1,2, Masanori Yoshino^1,2, Hideki Bou^1,2, Masao Ogata^1,2, Masanori Watanabe^1,2, Hideyuki Suzuki^1,2 and Eiji Uchida¹

¹Surgery for Organ Function and Biological Regulation, Graduate School of Medicine, Nippon Medical School
²Institute of Gastroenterology, Nippon Medical School Musashi Kosugi Hospital

The efficacy of total colonoscopy following a positive result of the fecal occult blood test (FOBT) for the early detection of colorectal cancer and polyps was evaluated. A total of 1,491 patients with positive FOBT results underwent total colonoscopy at the Institute of Gastroenterology, Nippon Medical School, Musashi Kosugi Hospital, from April 2002 through July 2009. Abnormalities were found in 1,312 of the 1,491 patients (88.0%). Ninety-six of the 1,491 patients (6.4%) were found to have early cancer, but 59 patients (4.0%) were found to have advanced cancer. The early cancers were treated with endoscopic mucosal resection or endoscopic submucosal dissection in 81 patients, with laparoscopy-assisted colectomy in 10 patients, and with open surgery in 5 patients. Fifty-one of the 59 patients with advanced colorectal cancer underwent conventional open surgery, and 8 patients underwent laparoscopic surgery. The cancers detected were more likely to be early cancers than advanced cancers. In addition to malignancies, other abnormalities found included inner or external hemorrhoids, diverticula of the colon, ulcerative colitis, ischemic colitis, infectious colitis, and colorectal polyps. Our results show that a high percentage of lesions detected with total colonoscopy following a positive FOBT result are early colorectal cancers and polyps.

J Nippon Med Sch 2010; 77: 195-203

Keywords
fecal occult blood test, total colonoscopy, colorectal cancer surveillance

Correspondence to
Takuji Ozaki, MD, Institute of Gastroenterology, Nippon Medical School Musashi Kosugi Hospital, 1-396 Kosugi-cho, Nakahara-ku, Kawasaki, Kanagawa 211-8533, Japan
Otakuji0128@aol.com

Received, February 15, 2010
Accepted, April 2, 2010