Introduction: Pituitary adenomas are considered to be benign tumors that are diagnosed by its sympthoms (secondary to compression or hormonal secretion) or incidentally in an imaging technique performed because of another reason. Silent somatotrophinomas are very rare. This type of adenoma is typically large and despite it presents with mild or no acromegalic features it usually develops hormone secretion.
A case report: A 29-year-old spanish female with no previous disseases asked to her primary care doctor because of secondary amenorrhea. After that, she was studied in gynaecology consult by an exhaustive ultrasonography examination that was absoloutely normal and a blood test which rouled out pregnancy and showed low gonadotropine (LH and FSH), estrogen and prolactine levels with a normal kariotype (46 XX). With this findings, gynaecologists asked endocrinology department for its cooperation. She had no visual fields deffects, optical coherence tomography (OCT) was normal and she denied headache or other sympthoms of pituitary volumen expansion. No hyperandrogenism signs. Continuing with secondary amenorrhea study, endocrinologist ordered a pituitary MRI, that revealed a giant pituitary adenoma (41 mm high, 30 mm wide and 24 mm deep). It extended up and out of the sella turcica, stretching the optic chiasm, both cavernous sinus and pituitary infundibulum. A complete hormonal blood test revealed high somatomedin C (IGF-1) levels, without growth hormone (GH) supression at an oral glucosa tolerance test (OGTT). Waiting for surgery, somatostatin agonists treatment was performed, without any changes in tumour size. Endoscopic transsphenoidal surgery was performed in october 2018. However, the tumour was not completely removed. Some weeks after surgery visual fields and OCT were normal. Three months after surgery the patient doesnt have nor clinical nor biochemical hypopituitarism and she hasnt noticed any visual defects, despite it can still be found on MRI tumor remnant.
Conclusion: Giant pituitary adenomas (more than 4 cm adenomas) are commonly diagnosed by its clinical manifestations, thats why we should pay special atention to each sympthom isolated. This is a remarkable case of acromegaly with secondary amenorrhea as its only manifestation, which demonstrates the importance of a complete pituitary hormonal study in patients presenting with apparently nonsecreting macroadenomas.
References: 1. Sidhaye A, Burger P, Rigamonti D, Salvatori R. Giant somatotrophinoma without acromegalic features: more quiet than silent: case report. Neurosurgery. 2005;56:E1154. doi: 10.1227/01.NEU.0000157961.67867.E5.
18 - 21 May 2019
European Society of Endocrinology