Exemestane Treatment in a Male Patient With Concurrent Breast and Prostate Cancers: A Case Report.

BACKGROUND: Concurrent breast and prostate cancers in male patients is considerably rare. The first-line treatments for estrogen receptor (ER)-positive, progesterone receptor (PR)-positive breast cancer and prostate cancer include hormonal therapy, albeit they target different hormonal pathways. DISCUSSION: We present an 81-year-old man with concurrent stage IIB ER-positive, PR-positive breast cancer and metastatic prostate cancer who initially received letrozole and leuprolide. After concerns for progression of his breast cancer while receiving letrozole, the patient’s therapy was switched to exemestane, a steroidal structurally different aromatase inhibitor. His testosterone and prostate-specific antigen levels increased after the initiation of treatment with exemestane, and subsequently decreased after the discontinuation of exemestane treatment. CONCLUSION: Our case report shows that treatment with exemestane should be avoided in male patients with concurrent breast and prostate cancers as a result of the progression of prostate cancer. [ABSTRACT FROM AUTHOR]