A 10-year clinical experience with intermittent hormonal therapy for prostate cancer

To evaluate, over a 10-year period, the feasibility, efficacy, duration of action and adverse effects of intermittent hormonal therapy (IHT) in patients with advanced prostate cancer or biochemical recurrence after radical treatment.

Two hundred and thirty-three patients with prostate cancer have been included in an IHT protocol since 1992. Fifty-five patients had already been treated by radical prostatectomy (group A), 35 patients had received radiotherapy or a treatment with high-intensity focused ultrasound (HIFU) (group B) and 143 patients had not received any previous treatment (group C). Three-monthly injection of LHRH analogue combined with a non-steroidal antiandrogen was administered during the treatment phase ("on" phase). Treatment was stopped ("off" phase) when the PSA level fell below 4 ng/ml, regardless of the duration of the "on" phase. Criteria for resumption of hormonal therapy were PSA >20 ng/ml, PSA progression slope over the previous three months >5 ng/ml per month or recurrence of pain or urinary symptoms.

The median follow-up was 34.9 months (range: 13-151) and the median initial PSA was 28 ng/ml (range: 1-433). Five cycles were performed in the patients with the longest follow-up. The mean duration of cycles was gradually decreased from 19.6 months to 11.8 months. The "on/off" ratio was close to 30% regardless of the cycle or patient group. Ten patients (4%) died from their cancer during the study, with a median survival of 42.2 months. Six patients (2.5%) developed painful symptoms during IHT.

IHT ensures medium-term (three years) control of the disease, using a treatment resumption criteria of PSA >20 ng/ml and was not associated with major complications.