Efficacy and safety of 13 surgical techniques for the treatment of complex anal fistula, non-Crohn CAF: a systematic review and network meta-analysis

Background: Considering the difficulty of treating complex anal fistula (CAF), various surgical techniques exist in clinical work. However, none are ideal. Evidence on the efficacy and safety of different surgical treatments is scarce. We aimed to compare the outcomes of the 13 surgical techniques and tried to find the best surgical method for treating CAF. Materials and Methods: We searched worldwide databases, including Pubmed, Embase, Cochrane Library, Web of Science, CNKI, WanFang, VIP, and SinoMed, from inception to March 2023. All randomized controlled trials (RCTs) comparing the outcomes of 13 surgical techniques were included according to the PICO principles. The indicators of the cure rate, the recurrence rate, the complication rate, the operating time, the postoperative pain on day 1 (VAS), and the postoperative incontinence in month 1 (Wexner) were extracted and analyzed using STATA software 15.1, Review Manager 5.4, and GeMTC14.3. Results: Twenty-eight RCTS with a total of 2274 patients were included in the network meta-analysis. There was no statistically significant difference in the comparison among any surgical interventions in terms of the cure rate ( P >0.05 Table 2) and recurrence rate ( P >0.05 Table 3). However, in terms of complication rate, fistulectomy was lower than FPS (Median: 0.14; 95% CI: 0.02, 0.70) or fistulotomy (Median: 0.09; 95% CI: 0.01, 0.55), and fistulotomy was lower than EAFR (Median: 0.24; 95% CI: 0.05, 0.84), LIFT (Median: 0.17; 95% CI: 0.02, 0.66) or LIFT-EAFR(Median: 0.11; 95% CI: 0.01, 0.69) ( P >0.05 Table 4). The surface estimated the advantages and disadvantages under the cumulative ranking (SUCRA). The ranking results indicated that fistulectomy might have the lowest complication rate (SUCRA=7.9%). Because the network results of the operating time, the postoperative pain, and the postoperative incontinence contained no closed loops, the results of their probability ranking could only be referenced, demonstrating that fistulectomy might have the shortest operating time (SUCRA=23.4%), VAMLIFT might have the lowest postoperative pain on day 1 (VAS) (SUCRA=0.4%) and LIFT might have the lowest postoperative incontinence in month 1(Wexner) (SUCRA=16.2%). Conclusion: Fistulectomy might have the lowest complication rate, which might be the relatively superior surgical technique for treating CAF.