I stumbled upon an abstract published at the end of February 2010 that raised a number of questions about hormone therapy (ADT) and its effect on the immune system. Coming out of the starting gate I assumed that ADT would adversely affect the immune system making us prone to falling victim to all sort of illness, both common and serious. However, this might not be the case.

Despite this assumption, when I reflect back on my general health since I began intermittent ADT (six years ago) I am aware that I have actually avoided many of the common health issues (colds etc.) that members of my families have suffered. I have asked if this is just a coincidence or if it is related to my being on ADT.

Given our interest in developing immune-based treatments for advanced prostate cancer like Provenge and Prostvac, the issue whether ADT causes changes in the immune responses of prostate cancer patients, and if the timing of changes has implications for the sequencing of immunotherapies in combination with androgen deprivation.

In a study performed by the Departments of Cancer Biology and Medicine, University of Wisconsin Carbone Comprehensive Cancer Center this issue was raised. The researchers took Peripheral blood mononuclear cells (PBMC) from men with advanced prostate cancer prior to their beginning ADT and at several time points thereafter. These cells were then analyzed for the frequency of specific lymphocyte populations, and their response to stimulation.

They found that men developed an expansion of the naïve T cell compartment which persisted over the course of ADT, together with an increase in effector cell response to stimulation, and the generation of prostate tissue-associated IgG antibody responses, implying a potential benefit to the use of ADT in combination with prostate cancer-directed immunotherapies.

The optimal timing and sequence of androgen deprivation with immune-based therapies awaits future experimental evaluation.

Hum Immunol. 2010 Feb 10. Epub; Morse MD, McNeel
PubMed Abstract

Joel T. Nowak, M.A., M.S.W.