Surgical cryoablation as an option for small renal masses in patients who are not ideal partial nephrectomy candidates: intermediate-term outcomes.

Objective: There has been increasing interest in surveillance and ablative techniques for small renal masses (SRM), given the increasing number being diagnosed at smaller sizes. Of the currently available ablative techniques, radiofrequency ablation and cryoablation have been the popular ones. We describe our intermediate-term outcomes with using cryoablation for SRM in patients who were not ideal candidates for partial nephrectomy. Materials and methods: Nineteen patients treated with cryoablation were included. Patients with renal lesions <4 cm were considered for cryoablation, and all patients were treated between 2002 and 2007. Access was either laparoscopic (transperitoneal) or via open surgical techniques. From 2002 to 2004, the CryoCare System (Endocare, Inc., Irvine, CA) was used, with probe sizes ranging from 3 to 5 mm. Before 2004, the SeedNet system (Galil Medical, Arden Hills, MN) was used, with 17-gauge (1.47 mm) IceRod cryoneedles. Recurrence-free survival (RFS) and overall survival (OS) were calculated using Kaplan Meier methodology. Results: The mean age was 56.7 years. The mean tumour size was 2.6 cm (range 1.2-4.0 cm). There were no intraoperative or postoperative complications in the 19 patients. One patient has been lost to follow-up; mean follow up was 41.6 months (range 7-84 months) in the cohort. Recurrence, defined as either increase in size of lesion or enhancement on follow-up imaging, was seen in 4 patients. There was 1 non-cancer specific death, and 1 cancer specific death. Conclusions: The 4-year RFS rate and OS rate were 83.6% and 94.1%, respectively, in patients with SRM who were unsuitable for partial nephrectomy. Objectif : Le diagnostic etant de plus en plus precoce, on note un interet croissant pour les techniques de surveillance et d’ablation des petites masses renales. Parmi les techniques actuelles, l’ablation par radiofrequence et la cryoablation sont les plus utilisees. Nous presentons ici nos resultats a moyen terme avec la cryoablation de petites masses renales chez des patients a qui la nephrectomie partielle ne convenait pas. Materiel et methodologie : Dix-neuf patients traites par cryoablation ont ete inclus. Les patients presentant des lesions renales de < 4 cm etaient consideres, et tous les patients ont ete traites entre 2002 et 2007. L’abord se faisait par laparoscopie (transperitoneale) ou par chirurgie ouverte. De 2002 a 2004, on a eu recours au systeme CryoCare (Endocare, Inc., Irvine, Calif.), avec des sondes de 3 a 5 mm. Avant 2004, on utilisait le systeme SeedNetMC (Galil Medical, Arden Hills, Minn.), avec des cryo-aiguilles IceRod de calibre 17 (1,47 mm). Les taux de survie sans recurrence (SSR) et de survie globale (SG) ont ete calcules par la methode de Kaplan Meier. Resultats : L’âge moyen etait de 56,7 ans; la taille moyenne des tumeurs etait de 2,6 cm (de 1,2 a 4,0 cm). Aucun des 19 patients n’a presente de complication intra ou postoperatoire. Un patient a ete perdu de vue lors du suivi. La duree moyenne du suivi etait de 41,6 mois (7 a 84 mois). Quatre patients ont presente une recurrence, definie comme une augmentation de la taille de la lesion ou une lesion plus visible lors des epreuves d’imagerie de suivi. Un patient est decede de causes non liees au cancer, et un autre, des suites du cancer. Conclusions : Les taux de SSR et de SG apres 4 ans etaient de 83,6 % et de 94,1 %, respectivement, chez des patients avec petites masses renales a qui une nephrectomie partielle ne convenait pas.