Atypical granular cell tumor of the neurohypophysis: a case report with review of the literature.

A 76-year-old man had an atypical granular cell tumor of the neurohypophysis which showed pleomorphic nuclei, mitotic figures, and spindle-shaped cells, extremely rare findings to be encountered. Review of 45 patients with neurohypophyseal granular cell tumor revealed a ratio of 1:2 between male and female with the peak occurrence (31%) in the fifth decade, and with the mean age of 50 years. There were no patients below 20 years of age. The common clinical presentations included visual disturbances and endocrinopathies relating to sex hormones. Surgical removal was the treatment of choice. If it is possible, total extirpation should be attempted. Because of uncertain cellular origin, the lesion should be descriptively diagnosed as granular cell tumor although multiple terms have been proposed.