title: Significance of intraprostatic architecture and regrowth velocity for considering discontinuation of dutasteride after combination therapy with an alpha blocker: a prospective, pilot study.
abstract: OBJECTIVE
  We conducted a prospective single-center study to evaluate the possibility of discontinuation of dutasteride after combination therapy with an alpha blocker for benign prostatic hyperplasia (BPH).
  
  
  METHODS
  We prospectively treated BPH patients with an alpha blocker and dutasteride (0.5 mg/d). Patients who had been treated with alpha blockers against BPH for more than 2 months were eligible, and 20 patients were included in the study. After 6 months of combination therapy, dutasteride was discontinued. Patients were followed for 12 months after cessation. Prostate volume, intraprostatic architecture determined by transrectal ultrasound, peak urinary flow rate, postvoid residual urine volume, and the serum prostate-specific antigen level were evaluated every 6 months, and the International Prostate Symptom Score and overactive bladder symptom score (OABSS) every 3 months. Patients were allowed to restart dutasteride during the follow-up period according to their desire.
  
  
  RESULTS
  Twelve patients (12/20, 60%) restarted the combination therapy from 6 to 12 months into the follow-up period. For patients who restarted dutasteride, the prostate volume and OABSS had increased and worsened after discontinuation, respectively. A visible transition zone with a clear border on transrectal ultrasound at baseline and regrowth of the prostate after discontinuation of dutasteride were risk factors for restarting the therapy (Mann-Whitney U test: p=0.008, p=0.017).
  
  
  CONCLUSIONS
  Prostatic enlargement after discontinuation of dutasteride differs among patients. Rapid regrowth of the prostate leads to deterioration of storage symptoms and a tendency to restart dutasteride. Baseline intraprostatic architecture may be a predictive factor for whether the patient is a good candidate for discontinuation.
authors: Department of Urology, NTT East Corporation Sapporo Hospital, Sapporo, Japan.
authors: Tetsuya
authors: T
authors: Shindo
authors: Department of Urology, NTT East Corporation Sapporo Hospital, Sapporo, Japan.
authors: Kohei
authors: K
authors: Hashimoto
authors: Department of Urology, NTT East Corporation Sapporo Hospital, Sapporo, Japan.
authors: Takashi
authors: T
authors: Shimizu
authors: Department of Urology, NTT East Corporation Sapporo Hospital, Sapporo, Japan.
authors: Naoki
authors: N
authors: Itoh
authors: Department of Urology, Sapporo Medical University School of Medicine, Sapporo, Japan.
authors: Naoya
authors: N
authors: Masumori
mesh_terms: D058891:5-alpha Reductase Inhibitors / Q000008:administration & dosage / Q000009:adverse effects; D000317:Adrenergic alpha-Antagonists / Q000008:administration & dosage / Q000009:adverse effects; D000368:Aged; D016903:Drug Monitoring; D004359:Drug Therapy, Combination / Q000379:methods; D000068538:Dutasteride / Q000008:administration & dosage / Q000009:adverse effects; D005500:Follow-Up Studies; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D009929:Organ Size; D011446:Prospective Studies; D011467:Prostate / Q000000981:diagnostic imaging / Q000187:drug effects / Q000473:pathology; D017430:Prostate-Specific Antigen / Q000032:analysis; D011470:Prostatic Hyperplasia / Q000188:drug therapy / Q000473:pathology; D055502:Secondary Prevention / Q000379:methods / Q000706:statistics & numerical data; D016896:Treatment Outcome; D014463:Ultrasonography; D028761:Withholding Treatment
chemical_list: D058891:5-alpha Reductase Inhibitors; D000317:Adrenergic alpha-Antagonists; D017430:Prostate-Specific Antigen; D000068538:Dutasteride
keywords: 5-alpha reductase inhibitors; Dutasteride; Prostatic hyperplasia