Oscar Selvaggio1, Giovanni Silecchia1, Franco Lugnani³, Luigi Cormio1, Matteo Gravina2, Luca Macarini2, Giuseppe Carrieri1
1 Dep ofUrology, UniversityOf Foggia, Foggia (Italy); 2 Dep ofRadiology, UniversityOf Foggia, Foggia (Italy); ³DepofUrology, Universityof Lubiana, Lubiana (Slovenia)
Several options are available today for the treatment of small renal masses, defined as tumors not larger than 4 cm in diameter (T1a), including active surveillance (AS), thermal ablation (TA), and radical (RN) or partial nephrectomy (PNWe report our series of small renal masses treated with CT-guided percutaneous cryoablation in terms of safety and oncological results.
Materials and Methods:
From May 2014 to October 2017 25 patients (mean age of 72.5 years, range 61-84) with renal neoplasm diagnosis have been selected at our Urology Department; they satisfied the following inclusion criteria: tumor diameter <4 cm; clinical anesthesia contraindications to nephron-sparing surgery; informed consent. All patients underwent CT-guided percutaneous cryoablation, preceded by needle biopsy of the lesion.The cryablation consisted in a procedure with an argon/helium gas-based system (Endocare, HealthTonics Inc., Austin TX, USA), under local anesthesia. The number of used cryoprobes varied as a function of lesion’s size: 5 patients treated by 1 probe, 8 pts by 2 probes, 3 pts by 3 probes. At the end of the procedure, a CT scan with contrast medium was performed to evaluate the complete freezing of the lesion and possible local bleeding.The follow-up included CT abdomen-pelvis at 3, 6 and 12 months. The definition of incomplete treatment was the persistence of the lesion contrast enhancement (CE) at the end of the scan; the definition of relapse was the appearance of the CE to the 6-month control CT.
The mean size of the tumor was 3.5 cm (range 1.6-5.5). All patients underwent lesion biopsy, with the following hystological outcome: clear cell Renal Cell Carcinoma (RCC) 20/25 (80%); chomophobe (RCC) 1/25 (4%); oncocytoma 4/25 (16%). Of the 25 treated patients, 23/25 (92%) had an incidentaloma and 2/25 (8%) were post-radiofrequency ablation relapses. A mean of 2 cryoprobes (range 1-3) was used, depending on the size of the tumor, and 2 cycles of freeze-thaw of the duration of 10 minutes each in 9 patients, and 3 cycles of 5 minutes each in 7 patients were performed. 2.4 mm cryoprobes were used. Complications were: 1 asymptomatic transitional perirenal effusion, 1 lumbar pain well-controlled by analgesic drug. Hospital stay was 3 days (range 2-4). The mean follow-up was 21 months (range 1-41).No case showed incomplete treatment and local relapse or secondarisms at the CT abdomen-pelvis with contrast medium at 3, 6 and 12 months. The procedure did not affect renal function.
This study shows the efficacy and safety of percutaneous cryoablation of renal neoplasm, although characterized by a short follow-up. The procedure is easy to perform, with few peri and post-operative complications, well tolerated and accepted by the patient and represents a feasible therapeutic option in small renal masses.