title: Changes in hormone production of a recurrent silent corticotroph adenoma of the pituitary: a histologic, immunohistochemical, ultrastructural, and tissue culture study.
abstract: A 19-year-old man with blurred vision, headache, and no signs or symptoms of hormone excess was found to have a pituitary adenoma. The tumor was removed by a transfrontal approach. He had postoperative radiation therapy, but subsequently had three recurrences, all removed surgically. By histology, the tumor was a chromophobic, slightly acidophilic pituitary adenoma. Immunohistochemistry revealed the presence of adrenocorticotropin (ACTH) in all four biopsies, alpha-subunit of glycoprotein hormones, and, to a lesser extent, follicle-stimulating hormone (FSH) and luteinizing hormone (LH) in the third and fourth tumor resection specimens. Ultrastructurally, the tumor had typical features of a silent corticotroph adenoma subtype 2. In tissue culture, the second, third, and fourth specimens released ACTH, alpha-subunit, FSH, and LH and responded to corticotropin-releasing hormone with increased release of ACTH, alpha-subunit, FSH, and LH. To our knowledge only one silent corticotroph adenoma has been reported previously which expressed plurihormonality. Change in immunohistochemical profile in malignant tumors is a well-known phenomenon; however, it was not reported previously in benign pituitary adenomas. The factors accounting for changing tumor phenotype are unknown.
authors.affiliation: Department of Pathology, St Michael's Hospital, University of Toronto, Ontario, Canada.
authors.forename: I
authors.initials: I
authors.lastname: Felix
authors.forename: S L
authors.initials: SL
authors.lastname: Asa
authors.forename: K
authors.initials: K
authors.lastname: Kovacs
authors.forename: E
authors.initials: E
authors.lastname: Horvath
mesh_terms: D000236:Adenoma / Q000378:metabolism* / Q000601:surgery / Q000648:ultrastructure; D000324:Adrenocorticotropic Hormone / Q000378:metabolism*; D000328:Adult; D046508:Culture Techniques; D005640:Follicle Stimulating Hormone / Q000378:metabolism; D006801:Humans; D007986:Luteinizing Hormone / Q000378:metabolism; D008297:Male; D009364:Neoplasm Recurrence, Local; D010911:Pituitary Neoplasms / Q000378:metabolism* / Q000601:surgery / Q000648:ultrastructure
chemical_list: D000324:Adrenocorticotropic Hormone; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone