Focal cryoablation: a treatment option for unilateral low-risk prostate cancer

Authors


Abstract

Objectives

  • To assess oncological (biochemical and histological recurrence) and functional (urinary and potency) outcomes in patients with unilateral low-risk organ-confined prostate cancer (PCa) treated with focal cryoablation (FC).

Patients and Methods

  • From January 2009 to March 2012, patients with localized PCa who refused active surveillance were assigned to a FC protocol.
  • This was a prospective, single-arm cohort study. Inclusion criteria were: unilateral disease, clinical stage T1c to T2a, prostate-specific antigen (PSA) concentration <10 ng/mL, low volume index lesion and Gleason score ≤6 (3+3). Hemi-ablation was carried out using the PreciseTM cryoablation system (Galil Medical, Inc., Arden Hills, MN, USA).
  • Oncological (PSA values) and functional (International Prostate Symptom Score and International Index of Erectile Function (IIEF)-5 score) outcomes were analysed at 3-, 6- and 12-month follow-up.
  • The primary endpoint for oncological efficacy, no cancer in ipsilateral side, was based on the 12-month mandatory biopsy.

Results

  • A total of 48 consecutive patients with a mean age of 67 years were included. The median (interquartile range) follow-up was 13.2 (7.4–26.5) months.
  • Follow-up prostate biopsies were negative for the treated lobe in 86% of patients.
  • The mean PSA concentration dropped significantly at 3 months (by 55%) but did not correlate well with positive biopsy results.
  • Urinary symptoms were unchanged. A slight decrease in the IIEF-5 score was present at 3 months, but did not differ significantly from baseline at 6-month follow-up.
  • There were 15% grade 1 and 4% grade 2 complications (Clavien classification).

Conclusions

  • Focal cryoablation is a low-morbidity option in selected patients with low-risk PCa.
  • We showed PSA concentration to be an unreliable marker for monitoring FC and recommend a protocol of mandatory biopsies for follow-up.
  • A multicentre randomized controlled trial is necessary to confirm the low-morbidity and the biopsy-proven PCa cure rates.

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