Efficacy of intraoperative topical Sapylin (OK-432) for preventing lymph leakage following inguinal lymph node dissection in melanoma: a retrospective cohort study

OBJECTIVE: To evaluate whether intraoperative topical Sapylin (OK-432) reduces postoperative lymphatic leakage after inguinal lymph node dissection (ILND) in melanoma patients. METHODS: This retrospective study included 105 melanoma patients who underwent unilateral ILND (2022-2025). The study group (n = 51) received intraoperative topical Sapylin; the control group (n = 54) received saline. Both groups underwent Sartorius muscle flap coverage. Lymphatic leakage incidence, recovery indicators, and complications were compared. Logistic regression was used to identify risk factors. RESULTS: Lymphatic leakage was significantly lower in the Sapylin group (9.8% vs. 25.9%, P = 0.032). Multivariable analysis confirmed age ≥ 60 years as an independent risk factor (OR = 4.93, P = 0.01) and Sapylin use as an independent protective factor (OR = 0.30, P = 0.04). The study group also showed reduced total drainage volume, shorter drain removal time, faster wound healing, and shorter hospital stay (all P < 0.05). No significant between-group differences were observed in fever or surgical site infection. CONCLUSION: Intraoperative topical Sapylin is safe and effective for reducing postoperative lymphatic leakage and accelerating recovery after inguinal lymph node dissection for melanoma. TRIAL REGISTRATION: This trial was registered in the Chinese Clinical Trial Registry (ChiCTR) on September 23, 2025 (Registration Number: ChiCTR2500109640; URL: https://www.chictr.org.cn/showproj.html?proj=287559).