text: Carcinomas that metastasize into the pituitary gland are uncommon and typically seen in the elderly, with lung and breast cancers being the most prevalent, In breast cancer patients, metastases to the pituitary gland occur in approximately 6–8% of cases.
  Symptomatic pituitary metastases account for only 7% of reported cases. In those who are symptomatic diabetes insipidus often occurs, with rates approximately 29–71%. Other commonly reported symptoms include anterior pituitary dysfunction, visual field defects, headache/pain, and ophthalmoplegia.
  Treatment
  Treatment options depend on the type of tumor and on its size:
  Prolactinomas (microadenomas and macroadenomas) are most often treated with cabergoline or bromocriptine (both dopamine agonists) as the first line of treatment. Medical treatment usually effectively decreases tumor size as well as alleviates symptoms.  Pituitary adenomas are also followed by serial imaging (usually MRI) to detect any increase in size or mass effect on nearby structures. If medical therapy fails, the second option is usually transphenoidal pituitary surgery. A third line therapy is radiation therapy, proton therapy to shrink the tumor.
  Thyrotropinomas are treated with transsphenoidal pituitary surgery as the first line treatment option. Medical therapy is a second line treatment, and thyrotropinomas respond to treatment with somatostatin receptor ligands such as octreotide or lanreotide. In people with thyrotropinomas, treatment with somatostatin receptor ligands normalized thyroid hormone levels in 80-90% of people, and 42% of people had a decreased tumor size.