Beta human chorionic gonadotropin (β-hCG) expression in pituitary adenomas: relationship to endocrine function and tumour recurrence

• Published in: Pituitary Vol. 12; no. 3; pp. 190 - 195
• Main Authors: Doyle, Paul M, Thiryayi, Waziq A, Joshi, Abhijit, du Plessis, Daniel, Kearney, Tara, Gnanalingham, Kanna K
• Format: Journal Article
• Language: English
• Published: Boston Boston : Springer US 2009; Springer US; Springer Nature B.V
• Subjects: Adult; Aged; Aged, 80 and over; Chorionic Gonadotropin, beta Subunit, Human - metabolism; Endocrinology; Female; Gene Expression Regulation, Neoplastic; Human Physiology; Humans; Immunohistochemistry; Ki-67 Antigen - metabolism; Male; Medicine; Medicine & Public Health; Middle Aged; Neoplasm Recurrence, Local; Pituitary Neoplasms - metabolism; Pituitary Neoplasms - pathology; Pituitary adenomas; Beta-human chorionic gonadotropin (β-hCG); Endocrine function and tumour recurrence
• ISSN: 1386-341X; 1573-7403
• DOI: 10.1007/s11102-008-0155-x

The β subunit of human chorionic gonadotropin (β-hCG) is a marker of malignancies. Recent studies have also reported its expression in pituitary adenomas, although its significance is unclear. In this retrospective study, the authors quantitatively investigated the immunohistochemical expression of β-hCG in 123 patients undergoing surgery for pituitary adenomas and explored its relationship to the rest of the endocrine function, tumour recurrence and Ki-67 nuclear labelling. Based on the endocrine profile and immunohistochemistry, the pituitary adenomas were grouped into non-functioning (NFPA; N = 78) and functioning pituitary adenomas (N = 45). The latter included, 20 growth hormone (GH), 12 prolactin (PRL), 8 adreno-corticotrophin hormone (ACTH) and 5 mixed GH-PRL-producing adenomas. Ninety-three (76%) tumours were classified as primary and 30 (24%) tumours classified as recurrent adenomas. Immunohistochemically, 107 (87%) of pituitary adenomas expressed β-hCG, which was more common in NFPA (91%) than functioning pituitary adenomas (80%). β-hCG expression was not different between primary (86%) and recurrent pituitary adenomas (90%) and it was also not related to raised Ki-67 labelling. But, Ki-67 labelling was raised in recurrent pituitary adenomas (33%), compared to primary pituitary adenomas (11%). Although, β-hCG is expressed in the majority of pituitary adenomas, more especially in NFPA, it is un-related to the risk of tumour recurrence or cellular proliferation as measured by Ki-67 nuclear labelling. The high incidence of β-hCG expression in pituitary adenomas may provide a target for specific β-hCG-directed tumour therapies in the future.