Depressed-Type Early Colorectal Cancer

Kim, Hyun Shig; Lee, Kwang Real; Lim, Seok Won; Lee, Jong Kyun; Park, Weon Kap; Yoo, Jung Jun; Hwang, Do Yean; Kim, Kun Wuck

Abstract

BACKGROUND
AND AIM: While detection and removal of polyps on the basis of the adenoma-carcinoma sequence has been a principal procedure for endoscopists, a new type of early colorectal cancer has been recognized and has become a hot issue. This new ailment is a depressed-type early colorectal cancer, which has the characteristics of rapid growth and early invasion of the submucosa. Though once considered to be mere conjecture, many researchers claim that this cancer is a de novo carcinoma despite of its rare occurrence. Recently, 4 depressed-type neoplastic lesions were presented, which signifies the importance of recognizing that this type of cancer exists and is characterized by rapid growth and early invasion of the submucosa. METHODS: The 4 recently experienced depressed neoplastic lesions were reviewed and analyzed with respect to their endoscopic and clinicopathologic characteristics. The sizes of the lesions were measured in the fully inflated state of the bowel by using an endoscopic ruler. RESULTS: The sites of predilection were the descending and sigmoid colon. All of the lesions were under 10 mm, with 75% being below 5 mm. The largest lesion was an 8-mm, well-differentiated mucosal carcinoma. The overall malignancy rate was 25%. Light redness was observed in all patients. Distortion with air transformation of the mucosal fold was also recognized in all the patients. The main treatment was endoscopic mucosal resection, which amounted to 50%. CONCLUSIONS: Depressed colorectal neoplasms are real. They can be determined by their characteristic endoscopic features, such as light redness and distortion with air transformation of the mucosal fold. Because of their characteristics of rapid growth and early invasion of the submucosa, it is important to detect and manage them in an early stage, when their sizes are below 10 mm.