A 71-year-old man diagnosed with a stage T2 prostate tumor 2 years ago has elected watchful waiting, based upon an underlying heart condition that renders surgery potentially fatal. Recently, his PSA has jumped considerably, as have his levels of serum acid phosphatase. Which course of action would be least appropriate at this stage?
A) Combination treatment with an antiandrogen and a GnRH agonist
B) Treatment with bisphosphonates
C) Treatment with GnRH agonists alone
D) Treatment with ketoconazole

Question

Quizplus · Accepted Answer

The sharp rise in PSA, coupled with an increase in levels of serum acid phosphatase, is strongly indicative of metastatic cancer (which could be confirmed via molecular imaging such as MRI). Unopposed GnRH agonists initially cause LH and FSH levels to rise, stimulating the production of testosterone, which acts as fuel for the fire of prostatic metastasis. Thus, their use alone would not be appropriate. However, if these agonists are combined with antiandrogens, testosterone levels can be quelled from two different fronts simultaneously. Ketoconazole is a chemical castrating agent that could bring down testosterone levels rapidly and might be more appropriate for cases of advanced and widespread metastasis. Bisphosphonates address the effects of metastatic bone involvement and of osteoporosis resulting from antiandrogen therapy.

A 71-Year-Old Man Diagnosed with a Stage T2 Prostate Tumor