Results of a prospective study comparing the clinical efficacy of cryoablation of renal cell cancer followed by immediate partial nephrectomy.

ABSTRACT

PURPOSE: Evaluation if cryoablation of small renal tumours (RT) would facilitate the technique of laparoscopic partial nephrectomy (LPN) in a prospective study. PATIENTS AND METHODS: In a prospective non-randomised study between April 2007 and October 2009, 16 patients with a mean age of 68 years (48-80 years) and a peripherally located RT were candidates for nephron-sparing surgery (5 open partial nephrectomy (OPN), 11 LPN). Cryoablation of RT was followed in the same session by open (K-OPN) and laparoscopic (K-LPN) partial nephrectomy. Perioperative and follow-up parameters were estimated. A matched-pair cohort of 41 patients (20 OPN, 21 LPN) who underwent standard operations due to the same indication has been selected for retrospective comparison (controls). RESULTS: Mean age for K-OPN was 74 years (69-83) with mean blood loss 140 ml (50-200); for K-LPN 66.6 years (48-80) with 100 ml (50-700). All procedures were completed successfully without conversions (K-LPN), transfusions or intra-operative complications. Compared to OPN/LPN, K-OPN and K-LPN were associated with a longer operative time (P < 0.05) and a comparable postoperative hospital stay. There were no early postoperative complications. Cryoablation has not affected the histopathological evaluation of tumours or resection margins. Histopathology showed cytologic changes suggesting fresh coagulative necrosis, glomerular vascular congestion and interstitial haemorrhages following cryotherapy. One patient (K-LPN) developed a pararenal abscess necessitating puncture after 7 weeks. The follow-up (9-42 months) was uneventful. CONCLUSIONS: The current study shows that K-LPN is feasible without increasing procedure morbidity or compromising surgical and oncological outcomes. It adds no advantage to tumour excision. Pathological findings document early cryoablation effects but viable tissue.