Efficacy and feasibility of stromal vascular fraction containing adipose derived stem cells obtained from freshly prepared lipoaspirate for treatment of complex anorectal fistulas- A novel approach

Background

Anal fistulas are relatively common. Despite diverse treatment modalities and tremendous advance and optimization of surgical approaches, considerable recurrence and high failure rates are not uncommon especially after surgery for complex anal fistulas. Therefore, autologous adipose-derived stem cell therapy for the treatment of complex perianal fistula can be an innovative and promising option with potential high cure rate and long-term healing.

Aim

To assess the efficacy and feasibility intralesional administration of stromal vascular fraction containing autologous, adipose-derived stem cells prepared from fresh lipoaspirate for management of complex and recurrent anal fistula.

Methods

Totally, 28 patients with complex perianal fistulas were enrolled in this prospective case-series study from March 2018 and August 2022. They were 22 male and 6 females patient) with 38.8 years average ages (ranges from 26 to 54 years). All patients were assigned to receive intralesional injection with autologous freshly prepared adipose-derived stem cells from lipoaspirate suction in a concentration of 1 × 10⁷ cell/ml. The healing of fistulas, confirmed by clinical assessment and magnetic resonance imaging was evaluated at week 6 weeks, 12 weeks and 6 months after treatment. If no evidence of healing was not seen at 6 weeks, a second dose of same concentration was administered. In addition to fistula healing, adverse effect (functional outcomes), complications and procedure safety were also evaluated.

Results

The overall healing rate of fistulas treated by injection of ADSCs was 60.7% (17/28), while healing rate after first injection was 50% (14/28) and after second injection was 30% (3/10).Three patients were lost after first injection. During the follow up period of 6 months none of the patients who showed complete healing, recorded relapse of their fistulas (recurrence 0%). Further, none of the patients recorded complications or adverse reactions related to stem cell therapy during the study and none of them had worsening fecal incontinence during follow-up period. Postoperative pain assessed by.

VAS score was significantly low (>3). Fecal continence assessed by Wexner score of all patients was not changed or affected.

Conclusions

Injection of complex perianal fistulas by freshly prepared autologous ADSCs could be a valid and effective treatment modality. It is safe, feasible and minimally invasive procedure that lacks the risk of injury to anal sphincter complex, unlike other surgical procedures that endanger the anal continence.Further, second dose of ADSCs injection could improve the rate of healing, without adding adverse effects.