title: Focal prostate cryoablation: initial results show cancer control and potency preservation.
abstract: BACKGROUND
  Focal prostate cryoablation is the less-than-complete ablation of the gland with ice. Known tumor is ablated aggressively, whereas contralateral prostate tissue and surrounding structures are spared. This method offers targeted local cancer control aiming at sexual potency and urinary continence preservation in patients whose prostate cancer is believed to be unilateral.
  
  
  METHODS
  Patients who had a strong desire for preservation of sexual function and continence were informed of focal prostate cryoablation as an investigational treatment option for clinically organ-confined, unilateral tumor identified by color Doppler ultrasonography and confirmed by targeted and systematic biopsy. Only stage, not preoperative serum prostate specific antigen concentration (PSA) or tumor differentiation, was considered a potential contraindication. Thirty-one men with a mean age of 63 years underwent the procedure. Follow-up consisted of PSA measurement every 3 months for 1 year and every 6 months thereafter, with biopsies at 6 months and 1, 2, and 5 years and following any three consecutive PSA rises. Potency was determined with a patient questionnaire filled in without the physician present.
  
  
  RESULTS
  At a mean follow-up of 70 months, biochemical disease-free status, according to the ASTRO definition, was maintained by 92.8% of patients (26/28) and a 96.0% negative-biopsy rate (24/25) was observed. The one biopsy-positive patient was subsequently treated with full-gland cryoablation and remains disease free. Potency was maintained by 48.1% of patients (13/27) and another 40.7% (11/27) were potent with oral pharmaceutical assistance, yielding a total potency-preservation rate of 88.9%. No complications were observed.
  
  
  CONCLUSIONS
  Focal cryoablation can provide biochemical and local control of prostate cancer while preserving potency and continence. Further investigation is needed.
authors.affiliation: Prostate Institute, Community Memorial Hospital, Ventura, California 93003, USA. dbahn@cmhhospital.org
authors.forename: Duke K
authors.initials: DK
authors.lastname: Bahn
authors.forename: Paul
authors.initials: P
authors.lastname: Silverman
authors.forename: Fred
authors.initials: F
authors.lastname: Lee
authors.forename: Robert
authors.initials: R
authors.lastname: Badalament
authors.forename: Eric D
authors.initials: ED
authors.lastname: Bahn
authors.forename: John C
authors.initials: JC
authors.lastname: Rewcastle
mesh_terms: D000368:Aged; D001706:Biopsy; D003452:Cryosurgery / Q000009:adverse effects / Q000379:methods*; D018572:Disease-Free Survival; D007172:Erectile Dysfunction / Q000209:etiology / Q000517:prevention & control*; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011467:Prostate / Q000473:pathology / Q000601:surgery; D011471:Prostatic Neoplasms / Q000150:complications / Q000601:surgery*; D012189:Retrospective Studies; D011795:Surveys and Questionnaires; D016896:Treatment Outcome; D014549:Urinary Incontinence / Q000209:etiology / Q000517:prevention & control*