Aims:
Delayed bleeding is an important adverse event after colorectal endoscopic submucosal
dissection (ESD). We aimed to investigate the incidence and risk factors of delayed
bleeding after colorectal ESD, and to develop a risk scoring model for predicting
delayed bleeding.
Methods:
This retrospective multicenter study was performed at 5 centers. The derivation and
validation cohorts comprised 1189 patients from 1 center and 415 patients from the
other 4 centers. We investigated the incidence and risk factors of delayed bleeding.
Then, we developed a risk scoring model for predicting delayed bleeding using the
data of the derivation cohort. We validated the scoring system in the validation cohort.
Results:
Delayed bleeding occurred in 34 (2.9%) patients in the derivation cohort. In multivariate
analysis, the risk factors of delayed bleeding were tumor location in the rectosigmoid
colon (odds ratio [OR] 6.49, 95% confidence interval [CI] 1.96 – 21.42; P = 0.002),
large tumor (≥30 mm; OR 2.10, 95% CI 1.01 – 4.40; P = 0.048), and use of antiplatelet
agents except for aspirin alone (OR 4.04, 95% CI 1.44 – 11.30; P = 0.008). These 3
factors were incorporated into a risk scoring model for prediction of delayed bleeding
as the points of 2, 1, and 1, respectively. The area under the ROC curve for the risk
score in the derivation cohort was 0.726 (95% CI 0.645 – 0.808), implying good discrimination
ability. As the total score based on this system increased, the incidence of delayed
bleeding increased in the validation cohort. When patients in the validation cohort
were categorized into low- and high-risk groups, the incidence of delayed bleeding
after colorectal ESD was higher in the high-risk group than in the low-risk group
(4.2% vs. 1.9%).
Conclusions:
The risk scoring model incorporating tumor location, tumor size, and use of antiplatelet
agents can quantitatively predict the risk of delayed bleeding after colorectal ESD.