Endocrine Abstracts

Objective: To document clinical and laboratory presentations of FSH-staining pituitary adenomas, and to compare pure FSH-staining adenomas with mixed FSH and other anterior pituitary hormones staining ones.

Methods: We analysed our inpatient records for patients who underwent pituitary surgery, and analysed histopathological reports for FSH-staining pituitary adenomas. Immunostaining positivity was defined as immunostaining of ≥5% of the adenoma cells. Medical records including demographic features, symptoms at presentation and physical examination, as well as hormone profiles and dynamic tests for over or underproduction of anterior pituitary.

Results: Thirty-seven patients underwent pituitary adenomectomy with FSH-immunostaining (19 were pure FSH-staining, 18 were mixed adenomas) during January 2006–November 2009. Mixed adenomas were also immunostaining positive for LH in 12 (66.7%), ACTH in 13 (72.2%), GH 10 (55.6%), TSH in 12 (66.7), and for prolactin in 13 (72.2%) cases. Pure FSH-secreting adenomas cases were older (54.6±9.2 vs 44.5±11.3 years, P=0.006), mostly affected male gender (73.7%), and were larger in diameter (34.1±8.1 vs 24.0±10.3 mm), whereas mixed-tumors mostly affected younger women (72.2%). Clinical presentation and symptomatology were similar in both groups, whereas hypothyroidism tend to be more frequent in pure FSH-staining adenomas, although it didn’t reach to statistical significance (P=0.073)

Conclusion: FSH-staining pituitary adenomas are mostly pure in males, whereas they are mixed in women. In more than half of the cases they present with pituitary insufficiency, mostly with hypogonadism and growth hormone insufficiency. Critical insuffiencies, namely hypocortisolism and hypothyroidism that need a special attention, present in about half of the cases in pure adenomas, and in about one fourth of the mixed ones.