Giant prolactinoma in a prepubertal girl- challenges in the management

Outas Mariana Costache

doi:10.1530/endoabs.82.WB3

We report a case of a peripubertal 11 yr old girl with a diagnosis of macroprolactinoma. She was diagnosed 1,5 years before her presentation in our clinic in the context of headache. At the diagnostic, the MRI described a moderate enhancing homogenous mass- of 27/16/14 mm -centred on the diaphragm sellae –extended laterally in the right cavernous sinus in contact with the left optic nerve, anterior in the posterior segment of the olfactory sulcus and inferior to the Meckel cave. The provisional radiological diagnostic of meningioma was changed after finding a prolactin level of 67585 mUI/l. After three months of 1 mg Cabergoline weekly treatment, the serum prolactin level falls 10%. She lost from follow up while continuing treatment. August 2021- due to increased headaches, she addressed to the endocrinology and a new assessment was done with progressive tumour dimension on MRI to 35/24/27 mm.

Hormonal evaluation (Aug 2021) on 1 mg CBG weekly
	normal range	value	CBG total dose
prolactin mUI/l	<210	184879 (80% recovery after PEG);	110 mg
IGF1	123-427	515.5
GH ng/mL	0.12-8.05	2.16
FSH	0.9-8.9	0.4
LH	<3.1	<0.3
estradiol pmoL/l	18.4-250	42
cortisol nmol/l	357	171-536
ACTH	24.38	7.2-63
TSH mUI/l	0.5-4.3	2.04
freeT4 pmoL/l	12-21	14.1
PTH pg/mL	15-65	21.3
Calcium	8.8-10.8	10.5
*CBG, Cabergoline total dose since diagnostic

Clinical: normal visual field, 1500 mL urinary output, BP 100/60 mmHg, height-146 cm (+0 SD, MPH=166 cm +/- 8.5 cm), Tanner Stage I- prepubertal.

Investigations planned:

SST, GH suppression test, Genetics

Principals and considerations of the treatment:

- a gradual increase of the Cabergoline to a dose of 3,5 mg/week – was obtained with good tolerance

- a decrease of 20% of the serum prolactin level in a month was registered after achieving the dose of 3 mg Cabergoline weekly - peripubertal age of the patient achieves normal serum prolactin the condition for a spontaneous course of the puberty

The first intention treatment in prolactinoma is dopamine agonists. Prolactinoma larger than 4 centimetres with prolactin levels above 21000 UI/l is considered a giant prolactinoma. Irrespective of the size, they are very responsive to medical treatment. Resistant prolactinoma is defined as failure to normalize prolactin levels or inability to achieve 50% volume shrinkage. Surgery is reserved in apoplexy, progressive neuro-ophthalmic syndrome, optical chiasm herniation, or leak cerebrospinal fluid while tumour shrinkage.

Endocrine Abstracts

WB3