Comparison of Intermittent and Continuous Androgen Deprivation Therapy in Prostate Cancer Patients: An Up-to-Date...

Androgen deprivation therapy first became the treatment of choice for advanced prostate cancer in the 1940s with Charles Huggins' discoveries. Eight decades later, androgen deprivation therapy has significantly evolved, and yet is still utilized in various ways to treat certain forms of prostate cancer. For local recurrence after failed primary treatment and for locally advanced and metastatic disease, continuous androgen deprivation therapy has been standard of treatment. However, intermittent androgen deprivation therapy has emerged as a therapeutic alternative to continuous androgen deprivation therapy. The purpose of this meta-analysis is to provide an update on mortality, specifically prostate cancer-specific and nonprostate cancer causes, in order to offer some guidance when selecting the appropriate form of systemic androgen deprivation therapy.

The PubMed database was searched for prospective randomized clinical trials. Inclusion and exclusion criteria were defined. Using statistical software, we analyzed random-effects models with the assumption that the data were randomly sampled, estimated the pooled log risk ratio, assessed heterogeneity, and created funnel plots to evaluate publication bias.

A total of 12 randomized clinical trials met all inclusion criteria for final analysis. There was no statistically significant difference in prostate cancer-specific mortality between intermittent androgen deprivation therapy and continuous androgen deprivation therapy (RR=1.10 [0.85-1.42]). The analysis of nonprostate cancer mortality favored intermittent androgen deprivation therapy over continuous androgen deprivation therapy, but the difference was statistically insignificant (RR=0.94 [0.76-1.17]).

These 2 treatment modalities can be considered as equivalent in long-term treatment outcomes. As intermittent androgen deprivation therapy is more cost-efficient and less likely to yield adverse side effects, future treatment guidelines should consider these advantages over continuous androgen deprivation therapy.