Immunohistochemical detection of prolactin in clinically non-functioning pituitary adenomas.

Our data confirm the observations that monohormonal silent prolactinomas are very rare but frequently silent PRL often co-expressed with GH or LH. Although in the whole population of patients with CNFPAs both sexes are equally represented, in the case of silent prolactinomas the female sex is prevalent. The observation of the higher rate of recurrent tumours within PRL-immunopositive adenomas versus PRL-immunonegative CNFPAs has to be confirmed on the larger material.