Men being treated for their prostate cancer with a gonadotropin-releasing hormone (GnRH) had a significantly increased risk for biliary disease compared with men who underwent no treatment, according to the results of a large, population-based study published in European Urology.
Of the 183,842 men aged 65 years or older with locoregional prostate cancer examined in the study, just under half had undergone androgen deprivation therapy (ADT) with a GnRH. At the end of study follow-up in 2009, 7.5% of men had developed biliary disease.
“ADT for prostate cancer causes a number of metabolic problems that are known to be risk factors for biliary disease in the general population,” Philip J. Saylor, MD, from the division of hematology and oncology, Massachusetts General Hospital, Boston. “The most prominent of these are obesity, in general, increased abdominal girth, in particular, elevated triglycerides, and insulin resistance.”
Saylor and colleagues found that men who did not undergo ADT had 13.4 cases of biliary disease per 1,000 person years compared with 15.7 cases for men on a GnRH (P < .001). This translated into one case of biliary disease per 435 men treated with a GnRH for a year, the researchers wrote.
“The magnitude of the increase was small but was notable for the facts that (a) most of these new diagnoses led to biliary procedures, and (b) the risk seemed to rise with increasing duration of androgen deprivation,” said Saylor.
Of the total study population, 6.8% of men had to undergo a procedure to treat the biliary disease. In addition, a statistically significant increased risk for biliary disease was found for use of a GnRH for 7 months or longer (7-12 months: HR = 1.07, P = .02; 13-24 months: HR = 1.15, P < .001; 25 or more: HR = 1.20, P < .001).
According to the researchers, the findings of the study would be best used as a renewed call to optimize the metabolic health of men receiving systemic therapy for prostate cancer.
“We should reserve therapy for the men who are most likely to benefit, and we should enthusiastically pursue healthy diet and lifestyle choices among men who need it,” Saylor said.