Efficacy of povidone-iodine against accidental tumor incision during nephron-sparing surgery: experimental study in patients with renal cell carcinoma

PURPOSE: Accidental tumor incision (ATI) can occur during nephron-sparing surgery (NSS) and correlates with recurrence and metastasis. This study investigated risk factors of intraoperative ATI in renal cell carcinoma (RCC) patients after NSS and the efficacy of povidone-iodine for ATI. METHODS: A retrospective analysis was performed on 150 consecutive stage I (pT1N0M0) RCC patients who underwent NSS at The Second Hospital of Tianjin Medical University between May 2010 and October 2015 for the causes of ATI. Furthermore, in vitro experiments investigated whether tumor cells remained on the surface of scissors and the effect of treatment with povidone-iodine on the number of remaining 786-O cells. RESULTS: Among the 150 cases, 15 showed ATI, of which three suffered local recurrence during a median follow-up of 56 months. Pseudocapsules, satellite nodules, and renal cystic tumors were observed in ATI cases. In vitro experiments showed that tumor cells remained on the surface of scissors after ATI during NSS and that 0.5% povidone-iodine effectively killed tumor cells in 30 minutes. CONCLUSIONS: The probability of ATI is high in patients with complex-type RCC during NSS. ATI potentially increases the chance of metastasis and local recurrence, and 0.5% povidone-iodine kills tumor cells more effectively than distilled water.