Percutaneous Cryoablation of Solitary, Sporadic Renal Cell Carcinoma: Outcome Analysis Based on Clear-Cell versus Papillary Subtypes.

PURPOSE: To evaluate treatment outcomes with percutaneous cryoablation (PCA) based on renal cell carcinoma (RCC) histology.

METHODS AND MATERIALS: Patients treated with PCA for a solitary, sporadic stage T1a RCC from 2003 to 2016 were identified from a single institution's renal ablation registry. Patients with multiple tumors, history of RCC, or genetic syndromes associated with RCC (n = 60); no specific RCC subtype determined from core biopsy (n = 66); RCC subtype other than clear-cell or papillary (n = 7); or less than 3 mo of follow-up imaging (n = 5) were excluded. In total, 173 patients met study inclusion criteria. Oncologic outcomes, clinical outcomes, and complications were evaluated based on tumor subtype.

RESULTS: Of the 173 patients who underwent PCA for a stage T1a RCC, 130 (75%) had clear-cell RCC (ccRCC) and 43 (25%) had papillary RCC (pRCC). Median tumor size was 2.9 cm (range, 1.3-4.0 cm). Technically successful cryoablation was achieved in all 173 patients. Local tumor recurrence developed in 6 patients with ccRCC (4.6%), new renal tumors developed in 1 patient (0.8%), and metastatic RCC developed in 1 patient (0.8%) who also had local tumor recurrence. No patients with pRCC showed local tumor recurrence, new renal tumors, or metastatic disease. The 5-year disease-free survival rate in patients with ccRCC was 88%, compared with 100% in patients with pRCC (P = .48). Nine patients (5.2%), all with ccRCC, experienced major complications (P = .11).

CONCLUSIONS: Percutaneous ablation is a viable treatment option for patients with clinical stage T1a pRCC and ccRCC. Percutaneous ablation may be a very favorable treatment strategy particularly for pRCC.