Role of Regenerative Medicine in Modern Treatment of Anal Sphincter Insufficiency

Anal sphincter insufficiency (ASI) is a prevalent condition that leads to fecal incontinence (FI) and a substantial decline in health-related quality of life. Literature reports an average ASI prevalence of 8% among adults, underscoring its significance as both a medical and social issue that requires improved diagnostic and therapeutic strategies. Conservative management, including pelvic floor muscle training, biofeedback therapy, and dietary modification, often provides only limited and temporary benefit. When conservative measures fail, minimally invasive procedures and, subsequently, surgical interventions are considered. However, even surgical approaches carry a substantial long-term recurrence risk. Regenerative medicine, particularly the use of stem cells as a primary or adjunctive therapeutic modality, has generated substantial interest. Studies show that adipose-derived mesenchymal stem cells (AD-MSCs) improve sphincter morphology and promote restoration of muscle fibers without direct differentiation into smooth muscle. Bone-marrow-derived mesenchymal stem cells (BM-MSCs) demonstrate similar effects, acting through paracrine signaling and immunomodulation to enhance muscle morphology and contractility. In contrast, the therapeutic potential of induced pluripotent stem cells (iPSCs) remains largely unexplored. At present, the evidence base for all stem-cell therapies remains limited, with no standardized treatment protocols being established. Robust confirmation of efficacy requires multicenter randomized trials. This review summarizes current data on ASI treatment and identifies priority directions for future research in regenerative medicine aimed at managing this condition.

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