Endocrine Abstracts

Prolactinomas are very rare, but usually more aggressive among children, than in adults. Although treatment strategies for prolactinomas in adults are well established and at present time the preference is given to dopamine agonists, the use of these drugs in pediatric patients is limited due to lack of information on safety and efficiency in this group of patients.

A 14-year old boy presented with absent puberty, obesity (weight +4σ) general weakness, tiredness, headaches and fainting episodes. Examination revealed left eyelid ptosis and left pupil dilation, bitemporal hemianopsia, PRL – 7341 mU/l, LH – 0.2 U/l, FSH – 1.5 U/l, testosterone – 1.5 nmol/l, normal TSH and free T₄, elevation of total cholesterol and low density lipoproteins. MRI showed giant pituitary adenoma (47×52×46 mm) with supra- and parasellar extension, compromising brain stem, frontal, temporal lobes and third ventricle.

After obtaining an informed consent from parents of the patient we started therapy with cabergoline 2 mg a week which was well tolerated and at 12 months resulted in shrinkage of prolactinoma (22×26×35 mm), widening of the visual fields. PRL level fell to 1943 mU/l, testosterone was 0.5 nmol/l, LH – 2.6 U/l, FSH – 2.5 U/l. The patient’s physical appearance changed to normal (weight +2σ), Tanner stage progressed in all regions from 0 to 1 point, and lipid profile parameters were inside reference ranges.

This clinical case that we report here demonstrates high efficiency and tolerability of cabergoline in a 14-year boy with giant prolactinoma, complicated by visual, neurological and metabolic disturbances, which allowed us to refrain from surgical treatment and to reduce the degree of complications.