Robot-Assisted Partial Nephrectomy for Patients with Multifocal Renal Tumors Arising in a Solitary Kidney: Report of Three Cases.

Background: Surgical treatment of synchronous multifocal renal tumors arising in a solitary kidney remains an extremely unique and stressful challenge, since it is not easy to completely remove multiple tumors and effectively preserve the renal function without perioperative complications. In this report, we describe our experience of three patients with multifocal renal tumors detected in a solitary kidney who were treated by robot-assisted partial nephrectomy (RAPN). Case Presentation: Two men and one woman were found to have two small renal tumors in a solitary kidney, and subsequently underwent RAPN at our institution. The location of the renal tumors and surgical approach in each patient were as follows: one tumor on the abdominal side and another on the dorsal side with a transperitoneal approach, both on the abdominal side with a transperitoneal approach, and both on the dorsal side with a retroperitoneal approach. In this series, after clamping the main renal artery and resection of one tumor, an inner running suture was placed, followed by early declamping of the renal artery and then renorrhaphy, and the same procedure was repeated to manage the remaining tumor. In all patients, the trifecta outcomes were achieved, and there were no changes in the chronic kidney disease stage 1 month after RAPN, resulting in no requirement of postoperative dialysis. Conclusion: Although it is necessary to carefully select optimal candidates, RAPN with an early declamping technique could be a safe and feasible approach for the treatment of patients with synchronous multifocal renal tumors arising in a solitary kidney, facilitating the complete resection of tumor foci, minimization of warm ischemic injury, and effective preservation of the renal function.