Plurihormonal adenomas. Analysis of 62 cases.

This paper deals with the cytological features of pituitary plurihormonal adenomas based on 62 cases examined by histology, immunohistochemistry, ultrastructural study and post-embedding immunogold electron microscopy, including double labeling. In GH-cell containing adenomas, there were 9 adenomas consisting of exclusively GH and PRL cells. The other 39 adenomas contained other hormones as well as GH and PRL. Other nine combinations of pituitary hormones or alpha-subunit were observed. Special emphasis was laid on the fact that a greater part of GH-producing adenomas (74% by immunostain) were PRL-producing, although the ratio of GH-cells to PRL-cells widely varied from case to case. Concerning the double labeling study on mixed GH-PRL secreting adenomas, we recognized the existence of secretory granules containing GH only, those containing PRL only, those containing both GH and PRL and those containing neither.