EP317 - Summative Analysis of Treatment for Complex Anorectal Fistula

Purpose/Background: Complex anorectal fistulas present a surgical challenge, requiring techniques that maximize healing while preserving continence. Standard approaches such as ligation of the intersphincteric fistula tract (LIFT) and advancement flap remain widely used, though failure rates and morbidity remain a concern. Alternative techniques have emerged to address these challenges, including autologous stem cell therapy, porcine dermal implants, porcine matrix plugs, video-assisted anal fistula treatment (VAAFT), and laser closure (FiLaC). This analysis compares the effectiveness, recurrence rates, and clinical advantages of alternative techniques to LIFT and advancement flap.

Methods/Interventions: We conducted a comparative review of published outcomes of various treatments for complex anorectal fistulas. We compared standard treatments (LIFT and anorectal advancement flap) to alternative treatments (autologous stem cell therapy, porcine dermal implants, porcine matrix plugs, VAAFT, and FiLaC). Primary outcomes were healing/closure rates, limitations of use, and morbidity.

Results/Outcomes: LIFT demonstrated closure rates ranging from 57-99% with a morbidity rate of 13.5%. Anorectal advancement flaps achieved healing rates of 68.7-80% but had a higher associated morbidity (27.8%). Autologous stem cell therapy showed a 42.2%-48.1% greater likelihood of maintaining closure without a significant increase in adverse events compared to placebo (RR 1.422-1.481), though comparisons are limited by study heterogeneity and lack of randomized controlled trials. Porcine dermal collagen mesh yielded an 80% closure rate with 20% morbidity in a small study (n=186). Porcine matrix plugs achieved the highest reported closure rate at 92% at 6 months but were associated with a morbidity of 34.5%. VAAFT showed healing rates of 68.5-83% with 11% morbidity. FiLaC had variable efficacy (50-71.4%) and 50% morbidity in one series (17/35), with limitations noted in complex or branching tracts and uncertain long-term durability. Across all techniques, outcomes vary with fistula anatomy, complexity, and surgeon experience.

Conclusion/Discussion: Alternative therapies for complex anorectal fistula provide options for treating complex anorectal fistulas, especially in high-risk or recurrent cases. However, traditional methods like LIFT and advancement flap remain benchmarks due to their predictability and established efficacy. There is a need for further randomized trials or direct comparison between emerging and standard techniques. While newer approaches aim to spare the sphincter and improve morbidity, none have conclusively surpassed LIFT or advancement flaps in long-term success for all fistula types.

Table 1: Analysis of fistula treatment method by closure rate and morbidity.