Factors impacting all-cause mortality in prostate cancer brachytherapy patients with or without androgen deprivation therapy

Abstract 

Purpose

Certain subsets of patients have an increased risk of all-cause mortality when androgen deprivation therapy (ADT) is used with definitive radiotherapy. We evaluated the relationship between pretreatment serum testosterone, age, and comorbidities on survival after prostate brachytherapy in men treated with and without ADT.

Methods and Materials

From October 2001 to September 2005, 803 patients underwent brachytherapy and 720 had a pretreatment serum testosterone. Comorbidities were prospectively recorded for each patient (body mass index>30, hypertension, diabetes, current smoker). Median followup was 5.0 years. 34.2% of the patients received ADT. Focus was on subset of men who might be expected to have more significant side effects associated with ADT.

Results

ADT did not significantly impact overall survival (OS) in men <65 years, >65 years, with one or no comorbidities, with more than one comorbidity, or with normal/high testosterone level. ADT use in men with low testosterone level was associated with decreased OS (83.6% vs. 93.1%, p=0.01). The adverse impact of ADT in men with low testosterone level was restricted to men with low testosterone level and more than one comorbidity (OS of 71.3% vs. 92.8%, p<0.01), with death from cardiovascular diseases accounting for almost all of the excess mortality. The subset of men with multiple comorbidities and normal/high testosterone level did not experience adverse OS with ADT.

Conclusions

Low pretreatment testosterone level may be a marker for men at increased risk of premature death with ADT. The combination of low pretreatment serum testosterone level and multiple preexisting comorbidities is associated with decreased OS when ADT is incorporated into treatment.

Keywords: Prostate cancer, Testosterone, Overall survival, Androgen deprivation therapy