Published online Jul 15, 2022. doi: 10.4251/wjgo.v14.i7.1337
Peer-review started: March 15, 2022
First decision: May 10, 2022
Revised: May 24, 2022
Accepted: June 22, 2022
Article in press: June 22, 2022
Published online: July 15, 2022
The incidence of laterally spreading tumors (LSTs) is continually increasing; however, the optimal strategy for resecting large colorectal LSTs is still under debate. Endoscopic submucosal dissection (ESD) is associated with a high en bloc resection rate, low risk of recurrence and perfect pathological analysis. However, the possibility of a positive postoperative pathological resection margin exists, which would require additional surgical procedures. Surgery has a high complication rate, high mortality and prolonged hospital stays.
Accurate preoperative assessment based on various risk factors to identify carcinoma and invasion depth is essential for selecting an appropriate therapeutic strategy.
This study aimed to identify the predictors of carcinoma, invasion depth and endoscopically unresectable lesions for colorectal LSTs and to facilitate appropriate preoperative selection.
This retrospective study analysed the endoscopic and histological results of consecutive patients who underwent ESD for colorectal LSTs in our hospital during a six-year period. The characteristics of the LSTs were compared by subtypes. Risk factors for high-grade dysplasia (HGD)/carcinoma and deep submucosal invasion (SMI) (invasion depth ≥ 1000 μm) were determined for each morphologic subtype.
Among the four subtypes, non-granular pseudodepressed (NG-PD) LSTs had the highest rate of HGD/carcinoma and deep SMI (invasion depth ≥ 1000 μm). NG-PD subtype and rectosigmoid location were the independent risk factors for deep SMI in adjusted multivariate analysis.
We demonstrated that it is highly recommend that NG-PD and granular nodular mixed (G-NM) LSTs are removed through ESD; given their substantial risk for deep SMI, surgery needs to be considered in NG-PD LSTs located in the rectosigmoid, especially those with positive non-lifting signs.
A risk score chart, which can determine the risk for carcinoma, invasion depth and endoscopically unresectable lesions for colorectal LSTs should be developed. It can help endoscopists in selective use of different types of endo-resection or to proceed to surgery instead of endoscopy.