Giant prolactinomas in adolescence: an uncommon cause of blindness.

INTRODUCTION: Prolactinomas in childhood and adolescence are rare. However, in male patients in particular they may become extremely large and invasive, resulting in visual impairment without necessarily producing endocrine symptoms. CASE REPORTS: We report on two adolescent males who presented with deteriorating vision over a long period of time and who had optic atrophy on examination. Magnetic resonance imaging identified tumours with extensive anterior skull base invasion and suprasellar extension. Prolactin levels in both patients were markedly elevated, and a diagnosis of prolactinoma was made. Bromocriptine treatment was started resulting in lowered prolactin levels, improved vision and tumour shrinkage on imaging.
CONCLUSION: A male child or adolescent presenting with diminished vision and found to have suprasellar or anterior skull base tumour should have their prolactin levels checked to rule out a prolactinoma, which can be successfully managed with medical therapy.