The study material included 167 plurihormonal
adenomas, which consisted of 31% of the surgically removed
pituitary adenomas that we collected during a 12-year period. The mean age of patients with plurihormonal
adenoma was 45.7 years (range 13-75 years). There were 86 men and 81 women. All tumours were fully classified by immunohistochemical staining for seven
pituitary hormones or subunits. Thirty immunohistochemical subtypes of plurihormonal
adenomas were recognized. Hormonal symptoms were present in 70% of patients, while serum hormonal levels were increased in 89% of patients. Most patients had symptoms related to only one of the
hormones and only 7% of patients had symptoms related to two
hormones. The most common hormonal symptom was
acromegaly (50%); symptoms related to
hyperprolactinaemia ranked second (20%). Double immunostaining of all the possible combinations of the
hormones was performed in 30 selected tumours, and they all showed mixtures of
hormones in individual
adenoma cells in any hormonal combinations studied. The latter finding supported the view that plurihormonal
adenomas are monomorphous
adenomas.
CONCLUSIONS: