Fig. 5

Immunostaining demonstrates areas composed of cells with faint GH expression containing fibrous bodies (arrow) (a immunoperoxidase – x20; insert – x40). Fibrous bodies are positive for cytokeratin CAM5.2 (b immunoperoxidase – x20); the transcription factor PIT-1 is expressed in the majority of the cells (c immunoperoxidase – x20); the Ki-67 labelling index is <3 % in all cases (d immunoperoxidase – x20)