ABSTRACT
A 64-year-old woman experienced an episode of disorientation in relation to time, place, and people, as well as of visual defect and impaired balance. Physical examination showed a bitemporal hemianopsia and truncal ataxia. Computerized tomography of the skull revealed a sellar mass consistent with the diagnosis of pituitary adenoma. The patient progressively lost consciousness and died. At postmortem examination, a pituitary neoplasm with arachnoid metastases was present. Metastatic cervical lymph nodes were also detected. Histologic aspects of the primary tumor and of lymph node metastases were quite similar. Immunohistochemical investigation revealed the epithelial origin of the neoplasm and failed to disclose endocrine activity. At ultrastructural examination, the cells of the primary tumor and of the metastases lacked specific granules. These findings support the evidence of a primary metastasizing pituitary carcinoma.