| Theme |
Can we change to treat for diminutive colorectal polyp ? |
| Title |
Clinicopathological features of diminutive colorectal polyps : Data from the Japan Polyp Study |
| Author |
Takahisa Matsuda |
Endoscopy Division, National Cancer Center Hospital |
| Author |
Yasushi Sano |
Gastrointestinal Center, Sano Hospital |
| Author |
Yasushi Oda |
Oda GI Endoscopy and Gastroenterology Clinic |
| Author |
Kazuhiro Kaneko |
Division of Digestive Endoscopy and Gastrointestinal Oncology, National Cancer Center Hospital East |
| Author |
Shin-ei Kudo |
Digestive Disease Center, Showa University Northern Yokohama Hospital |
| Author |
Hirokazu Taniguchi |
Pathology and Clinical Laboratory Division, National Cancer Center Hospital |
| Author |
Kinichi Hotta |
Division of Endoscopy, Shizuoka Cancer Center |
| Author |
Takahiro Fujii |
TF Clinic |
| Author |
the Japan Polyp Study Workgroup |
|
| [ Summary ] |
Colorectal cancer is the third most prevalent cause of cancer related mortality in Japan. In terms of secondary prevention, early detection and endoscopic removal of adenomatous polyps reduces the incidence and mortality rates for colorectal cancer. Therefore, colonic polyps with malignancy potential are routinely removed using endoscopic procedures. During colonoscopy, small and diminutive colorectal polyps are commonly encountered. It is estimated that at least one adenomatous polyp is detected in approximately half of all patients undergoing screening colonoscopy. We evaluated the clinicopathological features of diminutive colorectal polyps based on data from initial total colonoscopies (1st TCS) of the Japan Polyp Study (JPS). A total of 3,827 diminutive colorectal polyps (≤5 mm) were detected and removed removed endoscopically. There were 3,784 low-grade adenomas (98.9 %), 34 high-grade adenomas (0.9 %), 8 intramucosal cancers (0.2 %) and 1 submucosal invasive cancer (0.03 %). In terms of distribution, 1,354 lesions (35.4 %) were located in the transverse colon (22.1 % : sigmoid colon, 20.5 % : ascending colon, 10.5 % : descending colon, 6.3％：rectum, 5.2 % : cecum). With increased patient age, the distribution of diminutive polyps shifted to the right-side of the colon. Morphologically, the prevalence of "depressed lesions [IIc/IIa + IIc/Is + IIc (NPG type)]" was much lower [27/3,827 (0.7 %)] than that of polypoid and flat lesions. However, the incidence of high-grade adenomas or cancers increased to as much as 11 %. Therefore, we should pay closer attention to identification of diminutive depressed colorectal lesions during screening and surveillance colonoscopy. |