title: Intermediate-term outcomes after renal cryoablation: results of a multi-institutional study.
abstract: OBJECTIVE
  To present intermediate-term oncologic efficacy of cryoablation (CA) for the treatment of patients with small renal masses in a multi-institution multisurgeon cohort.
  
  
  METHODS
  We retrospectively reviewed billing records and tumor registries, identifying 116 renal tumors in 116 patients treated with CA by six surgeons at four institutions. Patient age, sex, tumor size, RENAL nephrometry score, complications, and recurrences were recorded.
  
  
  RESULTS
  One hundred-sixteen patients (66.4% male, 33.6% female) with 116 tumors underwent renal mass CA with a mean follow-up of 27.4 months (range 1-112 mos). Mean tumor size was 2.76 ± 0.97 cm (range 1.1-5.5 cm). Twenty-seven complications occurred in 23 patients for an overall complication rate of 19.8%. Low-grade complications (Clavien I and II) accounted for 92.6% (n=25) of overall complications. Seven (6%) patients had enhancement on initial imaging and were considered incomplete ablations. Local recurrence and metastatic disease developed in four and one patients, respectively. In patients with biopsy-proven renal-cell carcinoma (RCC), the 2- and 5-year recurrence-free survival (RFS) probability was 0.83 (95% confidence interval [CI]: 0.74, 0.95) and 0.77 (95% CI: 0.60, 0.94), respectively. After excluding biopsy proven RCC patients with incomplete ablations, the 2- and 5-year RFS increased to 0.91 (95% CI: 0.82, 1.00) and 0.85 (95% CI: 0.71, 1.00) respectively.
  
  
  CONCLUSIONS
  CA of renal masses results in acceptable oncologic efficacy accompanied by a tolerable complication profile in a cohort with a mean follow-up of 27.4 months. CA remains a viable treatment option for small renal masses in selected patients.
authors: Department of Urologic Surgery, University of Minnesota, Minneapolis, Minnesota 55455, USA.
authors: Branden
authors: B
authors: Duffey
authors: Vannhu
authors: V
authors: Nguyen
authors: Erik
authors: E
authors: Lund
authors: Joseph S
authors: JS
authors: Koopmeiners
authors: John
authors: J
authors: Hulbert
authors: James Kyle
authors: JK
authors: Anderson
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002292:Carcinoma, Renal Cell / Q000601:surgery; D003452:Cryosurgery / Q000379:methods*; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D007668:Kidney / Q000473:pathology / Q000601:surgery*; D007680:Kidney Neoplasms / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000209:etiology; D016896:Treatment Outcome