Silent corticotropic adenoma of pituitary gland--a case report.

A 79-year-old man complained progressive visual impairment and Diplopia for 2 weeks. A big pituitary tumor was found and partially removed by the surgeon eventually. The tumor cells were chromophobic with H&E stain and exhibited focal positive staining with PAS. Immunoperoxidase method demonstrated moderate positivity for adrenocorticotrophic hormone (ACTH), while staining for growth hormone (G.H) and prolactin were negative. The patient was eucorticoid clinically and biochemically. Since silent corticotropic adenoma of the human pituitary gland is rarely encountered clinically, a review of the literature is included in this article.