[The value of functional tests in diagnosis of prolactinoma]

The present study in 37 hyperprolactinaemic patients was performed, to investigate the relationship between radiographic changes of the pituitary region and serum prolactin levels, clinical signs and the results of dynamic tests. Prolactin responsiveness after metoclopramide- and TRH-injection and the nocturnal profile of serum prolactin were examined in 25 women. The results of the dynamic tests did not correlate with the radiological diagnosis. However, serum prolactin concentrations correlated strongly with the radiographic evidence of a pituitary tumour. The results show, that prolactin stimulation tests and the evaluation of the nocturnal secretory pattern of prolactin are not useful for differentiating between adenoma and nonadenoma caused hyperprolactinaemia. However, determinations of prolactin serum levels are of great clinical importance in the diagnosis of prolactinomas.