Endocrine Abstracts

Introduction: Giant prolactinomas are rare tumours, they represent range from 0.5 to 4.0% of all pituitary tumours. We are presenting a patient with giant prolactinoma without visual field defects and any obvious clinical symptoms related to hyperprolactinemia and probably associated with alopecia universalis.

Case: 32 years old man has visited outpatient department of our hospital, complaining of severe headache for the last three years. He underwent brain CT scan and 4.8×5.8 cm pituitary macroadenoma was revealed. The first prolactin measurement (RIA) was 4409.0 mU/L (NR: 38–379 mU/L). Further evaluation revealed episodically lower testosterone levels (from 8.85 up to 12.6 nmol/L (NR: 9.26–35.1 nmol/L), and IGF-1 was near lower normal limit: −20.5 nmol/L (NR: 20.2–25.4 nmol/L). Other hormones were at normal range and neuroophthalmological assessments were without any pathological signs for all time of observation. Physical examination revealed AU and family history was confirmed - patient’s mother also suffered from AU. Treatment was started with cabergoline 2 mg per week and after two weeks the dose was increased to 3 mg per week. After one month of treatment prolactin decreased to 948.0 mU/L, after 3 months the prolactin concentration reached the normal range- 321.0 mU/L. The dose of cabergoline was increased further to 4 mg per week. After 6, 12 and 24 months of treatment concentrations of prolactin were 171.0 mU/L, 77.0 mU/L and 48.0 mU/L respectively. The patient was treated with dose 4 mg per week for another 12 months and the prolactin concentration remained suppressed. One month after start of the treatment, the MRI scan was performed: the size of pituitary adenoma was decreased to 2.7×2.1×4.2 cm. The positive dynamics on the MRI scans steadily persisted after 3, 12 and 28 months, according to the last MRI the size of macroadenoma was reduced to 2.5×2.6×2.8 cm. Just after two weeks of treatment, the patient’s well-being improved, after two months of treatment the headache disappeared. Alopecia remained unchanged. Genetic investigation with the aim to find possible genetic associations between giant prolactinoma, AU and primary hypopituitarism was started.

Conclusion: Giant prolactinoma with hypopituitarism (lower testosterone level, LH and IGF-1 lower normal level) possibly are independently associated with alopecia universalis in our case, comprehensive genetic testing is required. This clinical case demonstrates that cabergoline could be highly effective for the treatment of giant prolactinoma.