Published online Mar 28, 2019. doi: 10.3748/wjg.v25.i12.1502
Peer-review started: December 25, 2018
First decision: January 30, 2019
Revised: February 21, 2019
Accepted: February 22, 2019
Article in press: February 23, 2019
Published online: March 28, 2019
As the indication for endoscopic colorectal tumor resection has expanded in terms of tumor size and depth of tumor invasion, it has become apparent that local recurrence occurs in a significant proportion of patients treated via polypectomy, endoscopic mucosal resection (EMR), or endoscopic submucosal dissection (ESD). According to a previous meta-analysis, a high incidence of local recurrence of up to 50% after EMR has been reported. Although tumor size, intraprocedural bleeding, piecemeal resection, and high-grade dysplasia have been shown to be associated with local recurrence of colorectal adenoma after EMR, the related risk factors after polypectomy, EMR, and ESD have not been identified. Additionally, the appropriate interval of endoscopic surveillance for colorectal tumors with a high risk of local recurrence has not been established, although the American Cancer Society recommends an interval of 3 to 6 mo for follow-up endoscopic examinations after piecemeal resection for large or sessile polyps.
We need to be cautious in the comparison of our data with those obtained in Western countries due to the difference in endoscopic resection methods.
We attempted to clarify the clinicopathological characteristics of recurrent lesions after endoscopic colorectal tumor resection and determine the appropriate interval.
Three hundred and sixty patients (1412 colorectal tumors) who underwent polypectomy, EMR, or ESD and received endoscopic surveillance subsequently for more than one year to detect local recurrence were enrolled in this study. Although most previous reports successfully identified lesional factors associated with the local recurrence of colonic tumors after endoscopic treatments, such as tumor sizes, endoscopic findings, and tumor locations, few reports have tried to identify patient factors, such as age, sex, history of colonic tumors, and diabetes. In this study, we performed univariate and multivariate analysis to identify patient factors associated with local recurrence.
Local recurrence was observed in 31 of 360 (8.6%) patients [31 of 1412 (2.2%) lesions] after colorectal tumor resection. Piecemeal resection, tumor size of more than 2 cm, and the presence of villous components were associated with colorectal tumor recurrence after endoscopic resection. Of these three factors, the piecemeal resection procedure was identified as an independent risk factor for recurrence. Colorectal tumors resected into more than five pieces were associated with a high risk of recurrence since the average period from resection to recurrence in these cases was approximately 3 mo. The period to recurrence in cases resected into more than 5 pieces was much shorter than that in those resected into less than 4 pieces (3.8 ± 1.9 mo vs 7.9 ± 5.0 mo, P < 0.05).
Local recurrence of endoscopically treated colorectal tumors depends upon the outcome of first endoscopic procedure. Piecemeal resection was the only significant risk factor associated with local recurrence after endoscopic resection. The interval between endoscopic resection for colorectal tumors and surveillance colonoscopy need to be determined based on the number of pieces.
The interval between endoscopic resection for colorectal tumors and surveillance colonoscopy need to be determined based on the number of pieces in prospective study.