Renal tumors: Salvage ablation successful in half of recurrences

The recurrence rate following thermal ablation of renal cortical tumors is 6%. About half of recurrences can be managed successfully with salvage ablative procedures, but 20% require extirpative surgery, according to retrospective findings obtained from databases from 10 U.S. centers.

"You could argue that it’s very important to counsel patients on what the recurrence rate is after an ablative procedure and how these are managed because the national trends for ablation are going much higher for patients with index renal masses," first author Jay Raman, MD, of Hershey Medical Center, Hershey, PA, told Urology Times.

Although partial nephrectomy is becoming the standard for managing localized renal tumors, cryoablation and radiofrequency ablation represent minimally invasive alternatives to partial nephrectomy. In AUA guidelines for the management of small renal masses, ablation and active surveillance are presented as options for patients with clinical T1a tumors who have major comorbidities and thus are at increased surgical risk, Dr. Raman said.

The databases included 1,265 patients managed by cryoablation (31%) or radiofrequency ablation (69%). Seventy-seven patients (6.1%) developed a recurrence at a mean of 13.7 months. There was no significant difference in recurrence rate between cryoablation and radiofrequency ablation (4.9% vs. 6.6%, respectively).

Of the 77 initial ablation recurrences, 47 (61%) were an incomplete primary ablation, 29 (38%) were ablation zone recurrences, (mean: 20.3 months post-ablation) and one (1%) was a metastasis. Twenty-one of the patients underwent biopsy, all of which were positive for renal cell carcinoma.Fifty patients had salvage ablation, which was successful in 38 patients. (Twelve patients had recurrence after salvage ablation.) Partial or radical nephrectomy was performed in 13 patients.

Of the 12 patients who had recurrences after salvage, six had repeat salvage ablation (three had successful repeat salvage ablation and three had recurrence while on surveillance), three were managed with active surveillance, and three underwent radical nephrectomy.

The actuarial cancer-specific and overall survival was 94.8% and 89.6%, respectively, at the most recent follow-up.