SYMPTOMATIC PITUITARY METASTASES: TWO CASE REPORTS WITH CONTRASTING CLINICAL PRESENTATIONS

To report 2 interesting cases of pituitary metastasis (PM) with differing presentations, and briefly review the literature regarding the incidence, presentation, and natural history of PMs.

Case report and literature review.

Patient 1 had known widely metastatic papillary thyroid cancer and presented with signs and symptoms of anterior pituitary dysfunction. He was found to have an undetectable AM cortisol. Further lab evaluation showed complete anterior panhypopituitarism. Pituitary magnetic resonance imaging (MRI) revealed an infiltrative pituitary lesion, which was presumed to be a meta-static lesion from his thyroid cancer. Patient 2 presented with an acute increase in urinary frequency and polydipsia. Water deprivation testing confirmed central diabetes insipidus (DI). Brain MRI showed an infiltrative pituitary lesion, which was the first sign of recurrent metastatic colon cancer. Subsequently, he developed the rapid onset of complete anterior panhypopituitarism. Review of the literature shows that when PMs produce symptoms, the most common presentation has traditionally been central DI. However, this is shifting as the incidence of anterior dysfunction and cranial nerve abnormalities is rising in more recent reviews.

Central DI has traditionally been the most common presenting symptom of PM, however symptoms reflective of anterior pituitary dysfunction and cranial nerve abnormalities are being reported with increasing frequency. PM should remain in the differential in any form of pituitary dysfunction.