Endocrine Abstracts

Introduction

Thyrotropinoma is a rare pituitary tumor ( <2% of pituitary adenomas) arising from PIT1-lineage cells, which expresses and secrete TSH. In most cases, the etiology is unknown but rare cases have been described to arise in context of MEN 1 syndrome. Diagnosis is often delayed by confusion with primary hyperthyroidism, which determine the tumor to be already large and invasive at the time of diagnosis. GH and prolactin cosecretion is an increased factor of aggression. We present the case of a 17-year-old patient, female, diagnosed 10 years ago with a pituitary tumor with autonomous cosecretion of TSH and GH, in which the first symptoms were weight loss, sweating, fatigue and palpitations. Early imaging described a tumor size of 20/31/37 mm, with central necrosis and parasellar extension in the bilateral cavernous sinus, including the internal carotid artery, optic chiasm, with no limit to separate from the frontal gyrus. The patient underwent multiple operations (6 times) both transsphenoidal and transfrontal, in combination with gamma knife radiosurgery but without significant tumor control. The patology exam revealed pituitary adenoma positive for TSH and GH with a Ki67 proliferation index of 20%. The patient is negative for the AIP mutation. Under treatment with progressively increased doses of octreotide acetate and cabergoline, no tumor control was obtained. Thus, in 2017, the last transsphenoidal intervention was performed, followed by local pituitary radiotherapy, with secretory active tumor residue, for which lanreotide was administered in combination with cabergoline. The patient presents a stationary clinical and biological condition in the last 2 years, with a tumor remnant of 72/54/40 mm, with retro and left parasellar extension, with TSH values after dilution slightly decreasing (1020 IU/ml), with therapeutic efficacy of GH profile. The patient underwent total thyroidectomy for voluminous goiter in 2014, which revealed multifocal, encapsulated, papillary carcinoma, pT3b G1, radioiodotreated, currently cured. The patient has corticotroph insufficiency and diabetes insipidus in replacement therapy and a history of early puberty and hyperestrogenism TSH-induced.

Discussions

Thyrotropinoma, although a rare benign tumor, is a life-threatening disease, especially when associated with hormonal cosecretion and high rate of proliferation. The consequences determined by the mass effect (convulsions, headache, oculomotor paresis, blindness), post-surgical and post-radiotherapy complications (bacterial meningitis, corticotroph insufficiency, diabetes insipidus) as well as those after long administration of somatostatin analogues, represent a challenge in the evolution and the patient’s long-term prognosis.