Prolactinomas in childhood and adolescence are rare, accounting for less than 2% of all intracranial tumours (Hoffman et al. 2018). Clinical symptoms and signs of hyperprolactinaemia may manifest as delayed puberty, hypogonadism or galactorrhea, whereas tumour mass effects can present as headaches and vision impairment (Casanueva et al., 2006). In this clinical case study, we present the case of a 16-year-old female with primary amenorrhoea secondary to macroprolactinoma and explore the treatment options following a modest radiological and biochemical response to initial dopamine agonist (DA) therapy.
A 14-year-old female presented to her general practitioner with headaches, galactorrhea, hemianopia and primary amenorrhea. She had bitemporal hemianopia on visual field testing. The results of the initial laboratory tests in July 2021 included prolactin 26 286 mIU/L (Ref: 85-500) and magnetic resonance imaging (MRI) revealed a 28 x 18 x 15 mm pituitary mass with compression of the optic chiasm. Following tertiary endocrinology and neurosurgical reviews, medical management was recommended, and the patient was commenced on cabergoline 0.5mg weekly and gradually increased to a total of 3mg weekly. Despite a further 11 months of DA therapy, the patient remained amenorrheic and hyperprolactinaemic (4930 mIU/L, ref: 85-500) with new additional symptoms of low mood, lethargy, and weight gain. Visual field testing had improved with a 90% resolution of visual hemianopia. The patient underwent a transnasal transsphenoidal excision of the pituitary tumour. Post-operative MRI scans revealed a significant reduction in tumour mass however she remained hyperprolactinaemic and was recommenced on cabergoline. She remained amenorrhoeic and therefore was required to commence topical estrogen therapy.
We present the challenging case of managing a medically refractive macroprolactinoma during adolescence. Significant concerns included concomitant pubertal delay, reduced bone age, and delayed secondary sex characteristics. This case highlighted the need for additional management options including surgical and hormonal therapy.