title: Cryoablation for Small Renal Masses: Selection Criteria, Complications, and Functional and Oncologic Results.
abstract: BACKGROUND
  Cryoablation (CA) is a minimally invasive modality with low complication rates, but its use in urology is relatively recent.
  
  
  OBJECTIVE
  To summarize available evidence for CA for small renal masses (SRMs) and to assess the selection criteria, complications, and functional and oncologic results based on the latest CA literature.
  
  
  METHODS
  A systematic literature search of the Medline, Embase, and Scopus databases was performed in August 2014 using Medical Subject Headings and free-text protocol. The following search terms were included: kidney cryosurgery, renal cryosurgery, kidney cryoablation, renal cryoablation, kidney cryotherapy, and renal cryotherapy.
  
  
  RESULTS
  Due to the relatively recent mainstream utilization of CA and lack of long-term efficacy data from large prospective or randomized studies, most of the data available on CA are limited to treatment of SRMs in patients who are often older or are poor surgical candidates. The rates of major complications across the CA literature remain relatively low. Studies assessing renal function after CA suggest a degree of functional decline following CA because proper application includes freezing of a tumor margin; however, often this is not clinically significant. Specific oncologic outcomes should be evaluated in patients with biopsy-proven renal cell carcinoma; when SRM series include benign or unbiopsied tumors, the results of these outcomes are skewed. Although earlier series were suggestive of a higher recurrence rate after CA, some studies have challenged this view reporting recurrence rates comparable with extirpative nephron-sparing surgery.
  
  
  CONCLUSIONS
  CA represents an alternative approach to treatment for patients diagnosed with renal neoplasm. There is no consensus within the literature on the best patient selection criteria. Due to higher rates of treatment failure, it is often not offered to patients with minimal comorbidities and good life expectancy. In terms of functional outcomes, CA signifies a modality with minimum impact on renal function; however, well-designed studies precisely assessing this factor are lacking. CA is a minimally invasive modality with suitably low rates of complications, particularly if delivered via the percutaneous route.
  
  
  RESULTS
  Cryoablation (CA) represents an alternative approach for treating renal neoplasm. Excellent functional outcomes and low rates of complications make CA an ideal minimally invasive modality. Patient selection criteria and oncologic outcomes require further study.
authors.affiliation: Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH, USA. Electronic address: homi.zargar@gmail.com.
authors.forename: Homayoun
authors.initials: H
authors.lastname: Zargar
authors.affiliation: Department of Radiology, Mayo Clinic, Rochester, MN, USA.
authors.forename: Thomas D
authors.initials: TD
authors.lastname: Atwell
authors.affiliation: Department of Urology, University of Texas Southwestern Medical Center, Dallas, TX.
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Cadeddu
authors.affiliation: Department of Urology, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: Jean J
authors.initials: JJ
authors.lastname: de la Rosette
authors.affiliation: Department of Urology and Andrology, Paracelsus Medical University Salzburg, Salzburg, Austria.
authors.forename: Gunther
authors.initials: G
authors.lastname: Janetschek
authors.affiliation: Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Jihad H
authors.initials: JH
authors.lastname: Kaouk
authors.affiliation: Department of Urology, MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Surena F
authors.initials: SF
authors.lastname: Matin
authors.affiliation: Division of Urologic Surgery, Department of Surgery, Duke University Medical Center, Durham, NC, USA.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Polascik
authors.affiliation: Moffitt Cancer Center, Tampa, FL, USA.
authors.forename: Kamran
authors.initials: K
authors.lastname: Zargar-Shoshtari
authors.affiliation: Department of Urology, Mayo Clinic, Rochester, MN, USA.
authors.forename: R Houston
authors.initials: RH
authors.lastname: Thompson
mesh_terms: D002292:Carcinoma, Renal Cell / Q000556:secondary / Q000601:surgery*; D003452:Cryosurgery / Q000009:adverse effects; D006801:Humans; D007680:Kidney Neoplasms / Q000473:pathology / Q000601:surgery*; D018579:Patient Selection; D016896:Treatment Outcome; D047368:Tumor Burden
keywords: Complications; Cryotherapy; Function; Oncology; Renal cryoablation; Selection criteria; Small renal masses