Repeat ablative therapy in hereditary or multifocal renal cancer: Functional and oncological outcomes.

OBJECTIVES: To report managing renal tumors in patients at greater risk of repeated interventions (genetic predisposition, multifocal tumors) with thermoablative treatments (AT). A known significant challenge in these patients is the balance between nephron preservation and oncologic outcome. MATERIAL AND METHODS: This retrospective, single-center study was based on data from patients treated with one or more AT for hereditary or multifocal renal tumors between 2007 and 2017. All medical records were systematically reviewed, and 10 patients meeting inclusion criteria were selected. Six patients had confirmed von Hippel-Lindau disease, 1 Bird-Hogg-Dubé syndrome, 1 chromosome 3 translocation, and 2 had a presumed genetic predisposition. RESULTS: Median age at cancer diagnosis was 39.5 years (±8.9). Fifty-seven tumors, including 41 de novo tumors that appeared during follow-up, were treated with 32 AT sessions (cryotherapy or radiofrequency) with an average tumor size of 13.5 mm (±9) and a median RENAL score of 6 [5; 7]. One patient underwent concomitant partial nephrectomy for a 55 mm lesion which was close to the bowel. Treatment was unsuccessful in 2 cases, subsequently managed successfully by retreatment with AT. Median delay of appearance of de novo tumor after the first AT was 18 months [6 ; 24]. One patient had metastatic progression. Overall and cancer specific survival was 90% and 100%, respectively, with a mean follow-up of 7.5 years (±4.9). The mean decrease in Chronic Kidney Disease - Epidemiological Collaboration equation-estimated glomerular filtration rate at the end of follow-up was 5.5 ml/min/1.73 m2 (±24). CONCLUSION: This study suggests that AT allows to meet the oncological objectives whilst preserving renal function in patients with renal cancer at greater risk of repeated treatments.