INTRODUCTION
Excluding skin cancer, prostate cancer is the most common malignancy affecting men in the United States, accounting for ~33% of VA cancer cases. Androgen deprivation therapy (ADT) is considered standard of care in treating advanced prostate cancer. Pituitary apoplexy is a rare and morbid adverse event associated with GnRH agonist treatment. We describe a patient with advanced prostate cancer who developed pituitary apoplexy shortly after leuprolide therapy.
CASE PRESENTATION
A 70-year-old African-American male was diagnosed with a T2aN1M1 stage IVB prostate cancer, Gleason 4+5, PSA 19.5. Four hours after his first leuprolide injection, he developed vomiting, diaphoresis, myalgia, and a severe frontal headache. Brain MRI revealed a 2.4 × 1.3 × 1.3cm pituitary mass, suspicious for an adenoma with hemorrhage. Labs noted low TSH, prolactin, LH, growth hormone, ACTH, cortisol, and testosterone, consistent with pituitary apoplexy. He was treated with steroids. Three weeks later, testosterone levels remained very low. He started abiraterone and prednisone without further leuprolide.
DISCUSSION
Prostate cancer is ubiquitous among VA patients, and ADT with GnRH agonist is vital in their care. These medications stimulate the pituitary to release LH and FSH resulting in a negative feedback loop, ultimately decreasing the levels of testosterone. Common side effects of GnRH agonists include hot flashes, diaphoresis, and sexual dysfunction. We present a patient who started leuprolide for prostate cancer. Symptoms including a severe headache led to an evaluation confirming pituitary apoplexy. Literature review reveals ~ 21 cases of pituitary apoplexy associated with GnRH agonist treatment for prostate cancer, and apoplexy can occur immediately to months later Undiagnosed pituitary adenomas are common among these patients. Treatment includes pituitary surgery or conservative management. Further prostate cancer treatment needs investigation, but we propose that GnRH modifying treatment can be withheld while testosterone levels remain low.
CONCLUSIONS
Prostate cancer is extremely common in the VA population, and treatment with leuprolide is standard. Pituitary apoplexy is a rare, but devastating complication of this treatment, and providers should be aware of the symptoms in order to intervene quickly. Further testosterone lowering treatment may be withheld if testosterone levels remain low.