FSH-Producing Pituitary Macroadenoma: Report of 2 Cases with Clinical Manifestations of Hormone Excess

ABSTRACT Objective: Gonadotropinomas with signs related to hypergonadotropinemia have been rarely published. We report 2 clinical cases of follicle-stimulating hormone (FSH)-producing macroadenomas showing manifestations of hormone hypersecretion. Methods: The clinical, laboratory, and imaging findings are presented with a review of the literature. Results: A 51-year-old man was admitted to the hospital because of cranioencephalic trauma following seizures. He reported previous altered behavior, depression, sphincter incontinence, and visual troubles. Physical examination revealed signs of hypogonadism and increased bilateral testicular volume. Magnetic resonance imaging (MRI) showed a large lesion in the sellar-suprasellar area, with mass effect. Hormone testing showed high levels of FSH (517 mIU/mL) and low levels of both luteinizing hormone (LH) (2.2 mIU/mL) and testosterone (1.3 ng/mL). A partial resection of an immunopositive FSH adenoma was performed; FSH declined after surgery, but the patient died due to postsurgical complications. A 36-year-old woman was referred because of secondary amenorrhea and multiple bilateral ovarian cysts of 2 years duration. Wedge resection of both ovaries had been unsuccessful, and later studies showed a pituitary macroadenoma on MRI and high levels of FSH (20.2 mIU/mL) and estradiol (288 pg/mL), along with suppressed LH (0.5 mIU/mL). Total surgical extirpation of the adenoma, which stained positive for FSH, was performed. After surgery, the patient recovered regular menstrual cycles, the ovarian cysts disappeared, and hormone values normalized. Conclusion: FSH-hypersecreting adenomas should be considered in the differential diagnosis of women with irregular menses associated with bilateral multicystic enlargement of the ovaries and in men with large testicular size and elevated serum FSH. Abbreviations: FSH = follicle-stimulating hormone IGF-1 = insulin-like growth factor 1 LH = luteinizing hormone MRI = magnetic resonance imaging PRL = prolactin