Caution Urged with Prebrachytherapy AST
ORLANDO—Neoadjuvant androgen suppression therapy (AST) prior to brachytherapy may be associated with an increased risk of all-cause mortality in men with favorable-risk prostate cancer who have pre-existing cardiovascular disease (CVD).
AST often is given to shrink the prostate so men can undergo brachytherapy, not to improve prostate cancer prognosis. In men with low-risk disease, AST use has never been shown to improve prostate cancer outcomes.
Previous studies have suggested that AST administration in men with any pre-existing comorbidity is associated with a decreased risk in overall survival compared with men who have no comorbidity, and AST has been associated with poor cardiovascular outcomes in some studies.
Researchers studied 12,792 men who had low- or intermediate-risk prostate cancer. Subjects had a median age of 71 years (range 65-75 years); 4,531 men (35%) received AST for a median duration of four months (range three to five months).
After a median follow-up of about 3.8 years, 1,557 men died. Following adjustments for age and known prostate cancer prognostic factors, AST use was associated with a 60% increased risk of death in men with a history of cardiovascular comorbidity.
In light of the study's findings, clinicians need to be cautious about prescribing AST to treat prostate cancer patients, said lead study investigator Julia H. Hayes, MD, clinical instructor of medicine at Harvard Medical School in Boston. She reported findings here at the 2009 Genitourinary Cancers Symposium.
“Our findings suggest that AST should not be given without careful thought, particularly in men with pre-existing cardiovascular disease,” Dr. Hayes told Renal & Urology News.
“This study does not analyze the cause of death in these men. However, their history of CVD suggests that cardiovascular mortality is likely to have a significant role. The side effects of AST are just beginning to be understood, and it is possible that AST may lead to death in other ways as well.”