September 18th, 2012

Intermittent and Continuous Hormone Therapy are Equally Effective in Prostate Cancer Treatment


Hormone therapy given intermittently (with breaks) has proven to be as effective as hormone therapy given continuously in asymptomatic men with rising PSA levels after prostate cancer treatment, according to the results of a study published in the New England Journal of Medicine.

Hormone therapy—also called androgen deprivation therapy—is designed to block testosterone from stimulating the growth of hormone-dependent types of prostate cancer. Because continuous androgen deprivation therapy produces side effects such as osteoporosis, hot flashes, and loss of libido, and because many prostate cancers eventually become resistant to hormonal therapy, researchers continue to explore alternatives.

Intermittent hormone therapy is an alternative method of delivering treatment. With intermittent treatment, men receive hormonal therapy until they achieve a sufficient treatment response and then they take a break and have a period of no treatment. The cycle is repeated as needed. Intermittent hormone therapy may reduce side effects and delay hormone resistance.

To compare intermittent and continuous hormone therapy, researchers enrolled 1, 386 men who had rising PSA levels (>3ng/ml) after radiation treatment for localized prostate cancer. The men were randomized to receive intermittent or continuous hormone therapy. Intermittent therapy was delivered for eight months and was followed by a non-treatment period if there was no evidence of clinical disease progression and if the PSA level was less than 4 ng/ml and within 1 ng/ml of the previous measurement. Men in the intermittent group had their PSA level monitored every two months—once it exceeded 10 ng/ml, they began another eight-month treatment cycle.

The primary endpoint of the study was overall survival and secondary endpoints included quality of life and time to hormone-resistant disease. The study was stopped early when it became apparent that overall survival with intermittent therapy was no worse than with continuous therapy.

The median overall survival was 8.8 years among patients treated with intermittent therapy and 9.1 years among those treated with continuous therapy. Men who received intermittent therapy appeared to have better quality of life, especially in terms of physical function, fatigue, urinary problems, hot flashes, libido, and erectile function. The estimated 7-year disease-related mortality was 18 percent in the intermittent group and 15 percent in the continuous group, which was not statistically significant.

The researchers concluded that intermittent hormone therapy is as effective as continuous hormone therapy and may improve quality of life.


Cook JM, O’Callaghan CJ, Duncan G, et al. Intermittent androgen suppression for rising PSA level after radiotherapy. New England Journal of Medicine. 2012; 367: 895-903.

Copyright © 2012 CancerConsultants. All Rights Reserved.

Tags: Early Stage I-II (A-B) Prostate Cancer, Locally Advanced Stage III (C) Prostate Cancer, Metastatic Stage IV (D) Prostate Cancer, News, Prostate Cancer, Refactory/Recurrent Prostate Cancer, Uncategorized