Diagnosis and management of isolated pituitary metastasis from adenocarcinoma of unknown origin presenting as loss of libido.

Pituitary gland metastasis from primary tumours is uncommon on its own. Rarely, some of these primary tumours may be of unknown origin. This metastasis to the pituitary gland could manifest as diabetes insipidus, cranial nerve palsies, headaches, fatigue and other symptoms. In rare cases, it could present as loss of libido. We describe here this rare presentation, loss of libido, examine the diagnosis and management undertaken, and provide a systematic review of the literature for similar cases.