Functional Pituitary Tumor in an Adult Possibly Secondary to Long-Standing Myxedema

Abstract
A 35-yr-old woman with primary myxedema, diagnosed as hypothyroid at the age of 8, developed a large pituitary tumor after several years without thyroid hormone therapy. The patient had galactorrhea and menorrhagia, indicating that gonadotropin secretion was not impaired. It is possible that the pituitary tumor resulted from inadequate feedback of thyroid hormone on hypothalamic or pituitary centers regulating TSH release.