title: Clinicopathologic correlates of giant pituitary adenomas.
abstract: Giant adenomas comprise a clinical/therapeutic subset of pituitary adenomas that pose a surgical challenge. The study population consisted of 28 patients who had giant pituitary adenomas, which are defined as tumors with a diameter greater than 5cm. Clinically, five tumors (18%) were endocrinologically functional and 23 (82%) were not. During surgery, one tumor was radically excised, four were subtotally excised, 12 were partially excised, and 11 were biopsied. All of the tumors showed typical histological features of pituitary adenoma. Of the 23 clinically non-functional adenomas, 18 were gonadotrophic tumors, four were null cell adenomas and one was a silent corticotroph adenoma. The MIB-1 labeling indices ranged from 0.1% to 2.0%. The mean topoisomerase labeling index was 0.75%. Microvessel density ranged from 0.42% to 5.55%, and there was moderately intense immunostaining for vascular endothelial growth factor. The present study found giant adenomas to be invasive but slow growing, histologically benign and often gonadotrophic in subtype.
authors.affiliation: Section of Neuropathology, Department of Neurological Sciences, Christian Medical College, Vellore, 632004, Tamil Nadu, India. geetachacko@cmcvellore.ac.in
authors.forename: Geeta
authors.initials: G
authors.lastname: Chacko
authors.forename: Ari George
authors.initials: AG
authors.lastname: Chacko
authors.forename: Matilde
authors.initials: M
authors.lastname: Lombardero
authors.forename: Sunithi
authors.initials: S
authors.lastname: Mani
authors.forename: M S
authors.initials: MS
authors.lastname: Seshadri
authors.forename: Kalman
authors.initials: K
authors.lastname: Kovacs
authors.forename: Bernd W
authors.initials: BW
authors.lastname: Scheithauer
mesh_terms: D000236:Adenoma / Q000145:classification / Q000378:metabolism / Q000473:pathology* / Q000628:therapy*; D000293:Adolescent; D000324:Adrenocorticotropic Hormone / Q000378:metabolism; D000328:Adult; D018952:Antigens, CD34 / Q000378:metabolism; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D019394:Ki-67 Antigen / Q000378:metabolism; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D010911:Pituitary Neoplasms / Q000378:metabolism / Q000473:pathology* / Q000628:therapy*; D012189:Retrospective Studies; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D018952:Antigens, CD34; D019394:Ki-67 Antigen; D000324:Adrenocorticotropic Hormone