title: MR imaging-guided focal laser ablation for prostate cancer: phase I trial.
abstract: OBJECTIVE
  To evaluate the feasibility and safety of magnetic resonance (MR) imaging-guided laser-based thermotherapy in men with clinically low-risk prostate cancer and a concordant lesion at biopsy and MR imaging.
  
  
  METHODS
  This HIPAA-compliant phase I prospective study was approved by the institutional review board. Informed consent was obtained from all patients. Transperineal MR imaging-guided focal laser ablation for clinically low-risk prostate cancer was performed in patients with a Gleason score of 7 or less in three or fewer cores limited to one sextant obtained with transrectal ultrasonography (US)-guided biopsy and a concordant lesion at MR imaging. Lesions were targeted with a laser ablation system. Periprocedural complications were recorded. The International Prostate Symptom Score (IPSS) and the Sexual Health Inventory for Men (SHIM) score were collected before and after the procedure. MR imaging-guided biopsy of the ablation zone was performed 6 months after treatment. The prostate-specific antigen level, IPSS, and SHIM score before and after ablation were compared by using the Wilcoxon signed rank test.
  
  
  RESULTS
  Treatment was successfully completed in nine patients (procedure duration, 2.5-4 hours; mean laser ablation duration, 4.3 minutes). Immediate contrast-enhanced posttreatment MR imaging showed a hypovascular defect in eight patients. Self-resolving perineal abrasion and focal paresthesia of the glans penis each occurred in one patient. The mean (± standard deviation) IPSS and SHIM score at baseline were 5.8 ± 5.3 and 19.0 ± 8.0, respectively. Average score changes were not significantly different from zero during follow-up (P = .18-.99). MR imaging-guided biopsy of the ablation zone showed no cancer in seven patients (78%) and Gleason grade 6 cancer in two (22%).
  
  
  CONCLUSIONS
  Transperineal MR imaging-guided focal laser ablation appears to be a feasible and safe focal therapy option for clinically low-risk prostate cancer.
authors: Department of Radiology, University of Chicago, 5841 S Maryland Ave, Mail Code 2026, Chicago, IL, 60637, USA. aoto@radiology.bsd.uchicago.edu
authors: Aytekin
authors: A
authors: Oto
authors: Ila
authors: I
authors: Sethi
authors: Gregory
authors: G
authors: Karczmar
authors: Roger
authors: R
authors: McNichols
authors: Marko K
authors: MK
authors: Ivancevic
authors: Walter M
authors: WM
authors: Stadler
authors: Sydeaka
authors: S
authors: Watson
authors: Scott
authors: S
authors: Eggener
mesh_terms: D000368:Aged; D001706:Biopsy; D003287:Contrast Media; D005240:Feasibility Studies; D019786:Gadolinium DTPA; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D053685:Laser Therapy / Q000379:methods*; D053783:Magnetic Resonance Imaging, Interventional; D008297:Male; D008875:Middle Aged; D009010:Monte Carlo Method; D011446:Prospective Studies; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging / Q000601:surgery*; D018709:Statistics, Nonparametric; D016896:Treatment Outcome; D014463:Ultrasonography
chemical_list: D003287:Contrast Media; C064925:gadodiamide; D019786:Gadolinium DTPA