Cryoablation for clinically localized prostate cancer using an argon-based system: complication rates and biochemical recurrence

Objective To determine the complication rates and biochemical recurrence after cryoablation of the prostate, using an argon gas-based system, in patients with localized prostate cancer. Patients and methods Between October 1997 and June 1999, 35 patients underwent cryoablation of the prostate (19 after radiation therapy failure and 16 as a primary treatment for localized prostate cancer). All patients had biopsy-confirmed prostate cancer with no seminal vesicle invasion, negative bone scans and a negative lymph node dissection. Patients received 3 months of combined hormonal therapy before cryosurgery. One surgeon performed all the procedures. Biochemical recurrence was defined by an increase in prostate specific antigen (PSA) of greater than or equal to 0.2 ng/mL, above the PSA nadir, Results The complications were rectal pain (26%), urinary infection (3%), scrotal oedema (12%), haematuria (6%) and incontinence (6%). Complication rates were higher in those patients who failed after radiation therapy than in those who did not receive radiation (incontinence 11% vs 0%, rectal pain 37% vs 12%) but the difference was not statistically significant. Twenty-two patients (63%) had an undetectable serum PSA nadir (<0.1 ng/mL) after cryotherapy and 30 (84%) patients had a PSA value of <1.0 ng/mL. After a mean follow-up of 8.3 months (range 0.2-18), nine patients had biochemical recurrence. The biochemical recurrence-free survival (BRFS) was 70% at 9 months. Patients who had an undetectable PSA nadir had a statistically higher BRSF at 9 months than did patients who had a detectable PSA nadir (89% vs 55%, respectively, P = 0.03). Similarly, patients with a preoperative serum PSA level of <10 ng/mL had a statistically higher BRFS than patients who had a PSA level of >10 ng/mL (86% vs 42% at 9 months, P<0.001), Conclusion A PSA level before cryotherapy of <10 ng/ML and an undetectable PSA nadir after cryotherapy were associated with the highest BRFS. Cryoablation of the prostate, with low morbidity, seems to be a viable option in managing patients by salvage therapy after radiation therapy and for the primary treatment of clinically localized prostate cancer.