| Theme |
New Development of Laterally Spreading Tumor |
| Title |
Diagnosis of Infiltration Depth of Colorectal Laterally spreading Tumors with EUS |
| Author |
Seiji Shimizu |
Division of Gastroenterology, Osaka General Hospital of JR West Railway Company |
| Author |
Naohisa Yoshida |
Department of Gastroenterology, Kyoto Prefectural University of Medicine |
| Author |
Hideo Tomioka |
Division of Gastroenterology, Osaka General Hospital of JR West Railway Company |
| Author |
Koichi Uejima |
Division of Gastroenterology, Osaka General Hospital of JR West Railway Company |
| Author |
Wataru Fukuda |
Division of Gastroenterology, Osaka General Hospital of JR West Railway Company |
| Author |
Chihiro Yokomizo |
Division of Gastroenterology, Osaka General Hospital of JR West Railway Company |
| [ Summary ] |
We evaluated the efficacy of endoscopic ultrasound (EUS) for the diagnosis of cancer infiltration depth in colorectal laterally spreading tumors (LST). Sixty‒eight lesions were examined with a 20 MHz miniature ultrasonic probe (MUSP). The series included 39 granular‒type lesions (11 homogenous, and 28 nodular mixed types) and 24 non‒granular type ones. The depth of invasion was divided into SM‒slight ≥ and SM‒massive ≤, and the EUS and histological diagnoses were compared. The infiltration depth was correctly diagnosed using MUSP in 76.5 % of patients. Diagnostic failures were due to poor visualization caused by echo attenuation, failure to fill the lumen with water, and inability to obtain perpendicular cross‒sectional images. Submucosal or deeper levels of invasion were not identified in the granular type lesions, and EUS is considered unnecessary for this type. Since the site of involvement and the mode of invasion differ according to the macroscopic type of LSTs, the indications for EUS should be determined after considering its necessity and difficulty. |