Prolactin presents in all pituitary tumors of acromegalic patients.
Twenty-two consecutive cases of adenoma in acromegalic patients were studied immunohistochemically. All the tumors contained prolactin (PRL)-reactive cells (3% to 53% of the total number of tumor cells) as well as growth hormone (GH)-reactive cells (4% to 74% of the total number of tumor cells). All acromegalic cases studied were thus plurihormonal adenomas containing GH and PRL; no pure GH cell adenoma was present. Twenty cases were further examined at the ultrastructural level in conjunction with postembedding double-labeling immunoelectron microscopy; 15 of these cases were diagnosed as mixed GH cell-PRL cell adenomas. The previously diagnosed pure GH cell adenomas possibly may have contained PRL cells and thus should be considered as mixed GH cell-PRL cell adenomas. Mammosomatotroph adenomas were rare in this series. Double-labeling immunoelectron microscopy, using protein A gold particles of two different sizes, greatly facilitated the distinction among GH, PRL, and mammosomatotroph cells.
Furuhata
S
S
Department of Pathology, Kitasato University School of Medicine, Kanagawa, Japan.
Kameya
T
T
Otani
M
M
Toya
S
S
D000172:Acromegaly / Q000150:complications / Q000378:metabolism*; D000236:Adenoma / Q000150:complications / Q000378:metabolism* / Q000473:pathology / Q000648:ultrastructure; D000328:Adult; D000368:Aged; D005260:Female; D013006:Growth Hormone / Q000032:analysis; D006801:Humans; D008297:Male; D016253:Microscopy, Immunoelectron; D008875:Middle Aged; D010911:Pituitary Neoplasms / Q000150:complications / Q000378:metabolism* / Q000473:pathology / Q000648:ultrastructure; D011388:Prolactin / Q000032:analysis*
D011388:Prolactin; D013006:Growth Hormone