Introduction
The degree of fibrosis during colorectal ESD varies and sometimes makes the procedure itself difficult. Preoperative prediction of fibrosis is expected to help develop a reliable strategy.
Aims & Methods
Of 1309 colorectal ESD lesions performed at our hospital between April 2012 and September 2022, 953 lesions larger than 20 mm were included after excluding post-treatment recurrence, SMT, and other conditions. Intraoperative fibrosis was classified into F0 (none), F1 (mild), and F2 (severe).
Results
Fibrosis was observed in 192 (20.1%) patients (F1; 143, F2; 49). The tumor diameter (median, range) was 23 (20-135), 30 (20-210), and 35 (20-115) mm in F0, F1, and F2 groups, respectively. The rate of the cecum (%) was 13.3 : 29.4 : 16.3, which was higher in F1. Overall, bleeding was observed in 17 patients (1.8%) and perforation in 3 patients (0.3%), and the frequency was similar in each group. The curative resection rate (%) was 98.4:91.6:59.2, with F2 being significantly inferior. The long treatment time (≥120 minutes) (%) was 1.7 : 9.1 : 46.9, showing a significant difference between F0 vs F1 and F1 vs F2, and the dissection speed (mean±SD, mm2/min) was 25.9±14.5 : 23.2±13.6 : 15.3±10.6, which was significantly slower in F2. The predictive factors of F1 and F2: straddling the folds, prior biopsy, lesion diameter, site, and morphology, were included in the study, and multivariate analysis showed that the predictive factors of F1 were straddling folds (OR;2.07,95%CI;1.39-3.11), lesion diameter ≥50mm (OR;4.68,95%CI;2.45-8.94), biopsy (OR;6.44,95%CI;3.32-12.5), NGPD (OR;4.31,95%CI;2.37-7.83), and cecum(OR;3.73,95%CI;2.35-5.92). The predictive factors of F2 were straddling folds (OR;2.34,95%CI;1.21-4.51), lesion diameter ≥50 mm (OR;7.29,95%CI;3.03-17.5), biopsy (OR;5.07,95%CI;1.81-14.1), and protruded type (OR;6.44,95%CI;3.23-12.8).
Conclusion
Colorectal ESD for fibrotic lesions was safe, but the curative resection rate was low in F2. F1-specific predictors were cecum and NGPD, and F2-specific predictors were protruded type, suggesting that the choice of surgeon and strategy should depend on the expected degree of fibrosis.