Prolactin secretion in patients with chromophobe adenomas of the pituitary: incidence and presentation of hyperprolactinaemia: results of surgical treatment.

In order to assess the frequency of hyperprolactinaemia in patients with "functionless" pituitary tumours, serum prolactin concentrations have been measured (by radioimmunoassay) in 111 patients with enlargement of the sella turcica who do not have acromegaly, Cushing's syndrome or Nelson's syndrome. The diagnosis of a chromophobe adenoma was confirmed in 76 patients who underwent surgery and was presumptive in the remaining 35. 45 of 64 (70%) patients studied before treatment and 15 of 47 assessed only after pituitary surgery had hyperprolactinaemia. Patients with raised prolactin levels usually presented with amenorrhoea or impotence, whereas reproductive disorders were rare in normoprolactinaemic patients. In many cases the presence of an underlying pituitary tumour was not initially suspected. The results of pituitary surgery were assessed in 25 patients with a chromophobe adenoma; of the 21 hyperprolactinaemic patients, surgery was most successful in those who had a small tumour treated by transsphenoidal adenomectomy. In conclusion, chromophobe adenomas formerly described as "functionless" are commonly associated with hypersecretion of prolactin and the hyperprolactinaemic patients frequently present with amenorrhoea or impotence. Prolactin levels should be measured in all patients with AMENORRHOEA or impotence and in patients with known (or suspected) pituitary tumours, before or after pituitary surgery.