# Stereotactic Body Radiotherapy for Multiple Renal Cell Carcinoma Lesions in a Patient With Polycystic Kidney Disease After Partial Nephrectomy

## TL;DR

This paper presents a case where stereotactic body radiotherapy successfully treated multiple kidney cancer lesions in a patient with pre-existing kidney disease.

## Contribution

The study demonstrates the safety and effectiveness of SBRT for multiple RCC lesions in patients with compromised kidney function.

## Key findings

- SBRT was safely administered to four renal lesions with no acute toxicity observed.
- MRI follow-up showed stable disease and preserved renal function 29 months post-treatment.
- SBRT achieved long-term disease control even with a reduced dose in a complex clinical scenario.

## Abstract

Renal cell carcinoma (RCC) is the most common malignant tumor of the kidney. Stereotactic body radiotherapy (SBRT) has recently emerged as a promising non-invasive treatment option for patients with localized RCC. However, data on SBRT in cases involving multiple renal lesions and pre-existing chronic kidney disease remain limited.

We report a case of a 69-year-old male with a history of polycystic kidney disease and prior partial nephrectomy for RCC, who was found to have four new renal lesions during follow-up. At diagnosis of relapse, the patient was treated with SBRT using Cybernife®. All four lesions were treated simultaneously, with a total dose of 30 Gy in five consecutive fractions. No acute toxicity was observed. At the last follow-up, 29 months after SBRT, the MRI confirmed the stable disease observed at the previous controls. Renal function remained stable throughout the follow-up period.

This case supports the use of SBRT as a safe and effective alternative to surgery for patients with multiple RCC lesions and compromised renal function. Even with a reduced dose, SBRT achieved long-term disease control and preservation of renal function suggesting its suitability in selected complex cases.