# Ex Vivo Partial Nephrectomy and Autotransplantation for Complex and Multifocal Renal Cell Carcinoma at a Single Institution: A Case Series

## TL;DR

This case series shows that ex vivo partial nephrectomy and autotransplantation can safely treat complex kidney tumors while preserving kidney function.

## Contribution

The study presents a novel application of ex vivo partial nephrectomy and autotransplantation for complex and multifocal renal tumors.

## Key findings

- Four patients underwent the procedure with no postoperative surgical complications.
- Nine out of ten excised tumors had negative surgical margins.
- Renal function returned to non-significantly different levels by three months post-surgery.

## Abstract

Renal autotransplantation is a rare surgical procedure designed to preserve renal function in patients with complex urinary system diseases or highly complex renal tumors. Between 2012 and 2023, four patients underwent ex vivo partial nephrectomy (PN) and autotransplantation for complex renal tumors at our hospital. Two patients had bilateral multifocal renal tumors, including von Hippel Lindau (VHL) disease and hybrid oncocytic chromophobe tumor (HOCT). The remaining two patients had highly complex renal tumors with Preoperative Aspects and Dimensions Used for an Anatomical (PADUA) score of 12, one of whom had a solitary kidney. None of the patients experienced any postoperative surgical complications. Pathologically, nine of the excised tumors had negative surgical margins, except for one of the four tumors on HOCT. Postoperative renal function decreased at one month compared to preoperative renal function (P = 0.01); however, there was no significant difference at three months (P = 0.07). None of the patients had a local recurrence or metastasis at the latest follow-up.Ex vivo PN and autotransplantation are feasible and reasonable treatment methods for highly complex and multifocal renal tumors regarding safety, local tumor control, and preservation of renal function.