Radiotherapy for postoperative groin lymphatic fistulas: A systematic review of clinical outcomes and treatment planning.

Postoperative groin lymphatic fistulas are a common complication of vascular surgery and radical lymph node dissection, which may occur in more than 10% of patients. While conservative management remains the standard first-line approach, refractory cases often require invasive interventions. Low-dose radiotherapy has emerged as a potential alternative, despite limited clinical adoption and an incompletely understood mechanism of action. This systematic review evaluates the available evidence on radiotherapy for postoperative groin lymphatic fistulas, focusing on clinical outcomes, safety, and treatment characteristics. A systematic review was conducted in accordance with PRISMA guidelines, searching MEDLINE via PubMed from inception to June 2026. Studies reporting radiotherapy use for postoperative groin lymphatic fistulas in human subjects were eligible. Extracted data included study and patient characteristics, radiotherapy parameters, and clinical outcomes. Twelve retrospective studies published between 1978 and 2026 were included, encompassing 448 patients. Radiotherapy schedules varied in timing (7.5-29 days post-surgery), dose per fraction (0.06-3 Gy), and total prescribed dose (0.5-20 Gy). Most protocols targeted the lymphocele and adjacent tissues, with a median treatment volume of approximately 585 cc. Fistula closure rates ranged from 67% to 100%, with complete response achieved within 5-27 days. Side effects were limited; one study reported a 2.4% incidence of secondary pelvic malignancies potentially attributable to radiotherapy. Radiotherapy appears effective for postoperative groin lymphatic fistulas, achieving high closure rates with low-dose, short-course regimens. However, substantial heterogeneity and the absence of prospective evidence underscore the need for standardized protocols and future prospective studies.