A CASE OF PLEURI-POTENT PITUITARY MACROADENOMA

We report the case of a 47 year-old Chinese man with pleuri-potent pit uitary macroadenoma who presented clinically with features of acromega ly and thyrotoxicosis. Laboratory investigations revealed a raised ser um free thyroxine level with unsuppressed thyroid stimulating hormone (TSH) and elevated basal growth hormone (GH) and insulin like growth f actor I. Follicle stimulating hormone (FSH) was high, luteinizing horm one (LH) was normal, and the corresponding testosterone level was low. The ratio of alpha subunit to TSH was greater than one. Magnetic reso nance imaging revealed a pituitary macroadenoma with suprasellar exten sion. The endocrine profile improved promptly with Octreotide(R) thera py. Transphenoidal hypophysectomy was carried out, and an immunohistoc hemical study of the tumor cells was positive for TSH, FSH, LH, prolac tin, and GH. Pituitary hormones detectable in the serum as inappropria tely normal or elevated included TSH, GH, FSH, and alpha subunit. The clinical picture of a pituitary tumor causing thyrotoxicosis, acromega ly, and an elevated FSH level has not been reported previously.