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 >/= 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.