Intermittent versus continuous androgen deprivation therapy to biochemical recurrence after external beam radiotherapy: a phase 3 GICOR study.

PURPOSE

We compared biochemical control and quality of life with intermittent (6 months) versus continuous (36 months) androgen deprivation therapy (ADT) in a non-inferiority randomized phase 3 trial in patients with biochemical failure (BF) after external beam radical radiotherapy (EBRT).

MATERIALS AND METHODS

Patients were stratified according to the Gleason score (GS) and were classified as low risk with a GS < 6 and 7 (3 + 4) and high risk with a GS of 7 (4 + 3) and >7. Patients were followed with PSA determinations and quality-of-life assessments (QLQ C-30 and QLQ PR-25) every 6 months for a period of 3 years. BF after radiation was defined as a PSA level of nadir +2 ng/ml. Disease progression (DP) after ADT was defined as PSA ≥4 ng/ml (BF) and/or metastases.

RESULTS

Seventy-seven patients were included in this multicenter phase 3 trial from 2005 to 2009. Thirty-eight and 39 patients were included in the intermittent and continuous groups, respectively. The median follow-up for both groups was 48 months (40-68). DP after ADT in the intermittent group was seen in three patients (distant metastases in one patient) versus 0 in the continuous group. The QLQ-C30 and QLQ PR-25 scores did not show any statistically difference between the two ADT groups.

CONCLUSIONS

No significant differences were seen in DP and QLQ between intermittent (6 months) and continuous (36 months) ADT in patients with BF after EBRT.