Zhi-Jie Cong1, Liang-Hao Hu2, Jun-Tao Ji2, Jun-Jie Xing3, Yong-Qi Shan3, Zhao-Shen Li2, En-Da Yu3. 1. Department of Colorectal Surgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China; Department of Colorectal Surgery, Changhai Hospital, Second Military Medical University, Shanghai, China. 2. Digestive Endoscopy Center, Changhai Hospital, Second Military Medical University, Shanghai, China. 3. Department of Colorectal Surgery, Changhai Hospital, Second Military Medical University, Shanghai, China.
Abstract
BACKGROUND AND AIMS: Colorectal laterally spreading tumors (LSTs) are divided into homogeneous (LST-G-H), nodular mixed (LST-G-M), flat elevated (LST-NG-F), and pseudodepressed (LST-NG-PD) subtypes. We hypothesized that based on the rates of advanced histology, the recurrence rates of the LST-NG-PD and LST-G-M groups may be higher than those of the other subgroups. METHODS: Endoscopic submucosal dissection (ESD) was performed in 156 patients with a total of 177 LSTs. The clinicopathological features and long-term prognosis of ESD according to specific subtype were investigated. RESULTS: LSTs were most commonly found in the rectum, and the highest percentage of rectal lesions was observed in the LST-G-M group (71.1% vs overall 55.4%, P = .032). The LST-G-M lesions were larger (60 ± 22 mm vs 40 ± 33 mm, P = .034) than the LST-G-H lesions. The LST-G-M group also demonstrated more high-grade intraepithelial neoplasias (32.2% vs 10.8%, P = .003) and submucosal carcinomas (13.6% vs 1.5%, P = .010) compared with the LST-G-H group. The LST-NG-PD group exhibited the highest incidence of submucosally invasive cancer (16.7%). The overall perforation rate was 2.3%. The perforation rate in the LST-NG group was higher than that in the LST-G group (5.7% vs 0.8%, P = .047). All recurrences (7.7%) were found by colonoscopy without any detection of cancers, and no difference was found among the subtypes. CONCLUSIONS: No significant differences were observed among subgroups with 44.4 ± 16.3 months of follow-up. Considering that all recurrences were discovered by colonoscopy and most could be cured by repeated ESD, the LSTs of all subgroups require more intensive follow-up compared with smaller adenomatous lesions.
BACKGROUND AND AIMS: Colorectal laterally spreading tumors (LSTs) are divided into homogeneous (LST-G-H), nodular mixed (LST-G-M), flat elevated (LST-NG-F), and pseudodepressed (LST-NG-PD) subtypes. We hypothesized that based on the rates of advanced histology, the recurrence rates of the LST-NG-PD and LST-G-M groups may be higher than those of the other subgroups. METHODS: Endoscopic submucosal dissection (ESD) was performed in 156 patients with a total of 177 LSTs. The clinicopathological features and long-term prognosis of ESD according to specific subtype were investigated. RESULTS: LSTs were most commonly found in the rectum, and the highest percentage of rectal lesions was observed in the LST-G-M group (71.1% vs overall 55.4%, P = .032). The LST-G-M lesions were larger (60 ± 22 mm vs 40 ± 33 mm, P = .034) than the LST-G-H lesions. The LST-G-M group also demonstrated more high-grade intraepithelial neoplasias (32.2% vs 10.8%, P = .003) and submucosal carcinomas (13.6% vs 1.5%, P = .010) compared with the LST-G-H group. The LST-NG-PD group exhibited the highest incidence of submucosally invasive cancer (16.7%). The overall perforation rate was 2.3%. The perforation rate in the LST-NG group was higher than that in the LST-G group (5.7% vs 0.8%, P = .047). All recurrences (7.7%) were found by colonoscopy without any detection of cancers, and no difference was found among the subtypes. CONCLUSIONS: No significant differences were observed among subgroups with 44.4 ± 16.3 months of follow-up. Considering that all recurrences were discovered by colonoscopy and most could be cured by repeated ESD, the LSTs of all subgroups require more intensive follow-up compared with smaller adenomatous lesions.