Is proctoscopy sufficient for the evaluation of colorectal anastomosis prior to ileostomy reversal? A nationwide retrospective analysis of the Italian Society of Surgical Oncology Colorectal Cancer Network Collaborative group (SICO-CCN)

Aim: Several methods for assessing anastomotic integrity have been proposed, but the best is yet to be defined. The aim of this study was to compare the different methods to assess the integrity of colorectal anastomosis prior to ileostomy reversal. Method: A retrospective cohort analysis on patients between 1 January 2010 and 31 December 2020 with a defunctioning stoma for middle and low rectal anterior resection was performed. A propensity score matching comparison between patients who underwent proctoscopy alone and patients who underwent proctoscopy plus any other preoperative method to assess the integrity of colorectal anastomosis prior to ileostomy reversal (transanal water-soluble contrast enema via conventional radiology, transanal water-soluble contrast enema via CT, and magnetic resonance) was performed. Results: The analysis involved 1045 patients from 26 Italian referral colorectal centres. The comparison between proctoscopy alone versus proctoscopy plus any other preoperative tool showed no significant differences in terms of stenoses (p = 0.217) or leakages (p = 0.103) prior to ileostomy reversal, as well as no differences in terms of misdiagnosed stenoses (p = 0.302) or leakages (p = 0.509). Interestingly, in the group that underwent proctoscopy and transanal water-soluble contrast enema the comparison between the two procedures demonstrated no significant differences in detecting stenoses (2 vs. 0, p = 0.98), while there was a significant difference in detecting leakages in favour of transanal water-soluble contrast enema via CT (3 vs. 12, p = 0.03). Conclusions: We can confirm that proctoscopy alone should be considered sufficient prior to ileostomy reversal. However, in cases in which the results of proctoscopy are not completely clear or the surgeon remains suspicious of an anastomotic leakage, transanal water-soluble contrast enema via CT could guarantee its detection.