PITUITARY TUMORS-01 HYPERPROLACTINEMIA AS A CLINICAL MARKER OF INVASIVE PROLACTINOMAS

BACKGROUND: Prolactinomas can acquire an invasion feature and challenge the management. Many features of invasive pituitary adenomas have been investigated in the literature, from radiological, histopathological to molecular perspectives. Here, we have decided to focus on serum prolactin level and evaluate its behavior in invasive prolactinoma patients. METHODS: It is a retrospective and consecutive view of 75 prolactinomas patients registered at the Hassan II University Hospital of Fez in Morocco. Patients were categorized into two groups: invasive and noninvasive prolactinoma. A non-parametric predicted ROC curve was performed to investigate the sensitivity and specificity of serum PRL level according to the invasiveness. RESULTS: A total of 31 patients (41.3%) represented the invasive group and the mean age was 35.6 years old compared to the group of noninvasive (34,1 years old). Males are more likely to be affected by invasive tumor than women (<0,00001). Serum PRL level was higher (2048.6 ± 1882.4) in invasive prolactinoma (p=0.001) and almost all invasive tumors had a PRL level greater than 1000 ng/ml. The predicted ROC curve of the distribution of the serum PRL levels showed an area under curve (AUC) of 89.8% and the calculated value of the threshold to fit a good sensitivity of 80% and false positive rate of 11.6% was estimated to 900 ng/ml. CONCLUSION: Based on clinical manifestations, hyperprolactinemia and MRI scan, the prolactinoma patients – especially men – presenting a larger tumor size and serum PRL level higher than 900ng/ml, should be considered as an invasive prolactinoma patient. As a matter of fact, with those patients an appropriate treatment should begin as soon as possible.