A review on the diagnosis and treatment of patients with clinically nonfunctioning pituitary adenoma by the Neuroendocrinology Department of the Brazilian Society of Endocrinology and Metabolism

ABSTRACT Clinically nonfunctioning pituitary adenomas (NFPA) are the most common pituitary tumors after prolactinomas. The absence of clinical symptoms of hormonal hypersecretion can contribute to the late diagnosis of the disease. Thus, the majority of patients seek medical attention for signs and symptoms resulting from mass effect, such as neuro-ophthalmologic symptoms and hypopituitarism. Other presentations include pituitary apoplexy or an incidental finding on imaging studies. Mass effect and hypopituitarism impose high morbidity and mortality. However, early diagnosis and effective treatment minimizes morbidity and mortality. In this publication, the goal of the Neuroendocrinology Department of the Brazilian Society of Endocrinology and Metabolism is to provide a review of the diagnosis and treatment of patients with NFPA, emphasizing that the treatment should be performed in reference centers. This review is based on data published in the literature and the authors’ experience. Arch Endocrinol Metab. 2016;60(4):374-90.

Endocrinological and Morphological Characteristics of Clinically Nonfunctioning Pituitary Adenoma / 대한내분비학회지

Forth-nine patients with clinically nonfunctioning pituitary adenomas were evaluated clinically, endocrinologically and morphologically in this study.The results obtained were as follows.1) The mean age was 47.1 years(range 23 to 76 years), and 22 were male(44.9%) and 27(55.1%) female.2) The major clinical manifestations of male patients were visual disturbance(72.7%), headache(54.5%), loss of libido(45.5%), but those of female visual disturbance(59.6%), headache(48.1%), amenorrhea(48.1%), loss of body hair(25.9%), and galactorrhea(22.2%).3) All were macroadenomas evaluated by CT scan, and in the male patients 16(72.7%) were grade III and 6(27.3%) grade IV by Hardy classification, and in the female patients 6(22.2%) were grade II, 12(44.4%) grade III, and 9(33.3%) grade IV.4) The elevation of serum prolactin were observed 7(31.8%) out of male, and 24(88.9%) of female.5) Combined stimulation test revealed that GH insufficiency was 89.6%, ACTH 58.9%, LH 58.7%, FSH 51.1 %, and TSH 50.0% and hormone insufficiency more than 4 pituitary hormone was 54.2%.6) Prolactin response to TRH decreased in 12(70.6%) of 17 patients with normal basal prolactin, and 19(76.0%) of 25 with elevated prolactin.7) Immunohistochemistry revealed that null cell adenoma was 57.1%, gonadotrope adenoma 26.5%, plurihormonal adenoma 8.0%, silent corticotrope adenoma 4.0%, thyrotrope adenoma(2.0%), and lactotrope adenoma(2.0%).8) The ultrastructural characteristics examined by electron-microscopy were similar despite of immunohistochemical differences.In summary, the prevalance of clinically nonfunctioning pituitary adenoma was middle aged men and women, and their main symptoms were visual disturbance and headache. Hyperprolactinemia and pituitary hormone insufficiency more than 4 hormone were observed commonly. Most of them were null cell adenoma and gonadotrope adenoma examined by immunohistochemistry. Further study using modern techniques: cell culture, subunit-immunostaining. And Northern blot analysis of mRNA for pituitary hormone or subunit, will be needed to clarify null cell adenomas.