Macroscopic and microscopic views of a thymic tumour.
The whole tumour (a) is from a patient with Cushing's syndrome. The conventional histology of the tumour is shown in (b). The immunofluorescent staining in section (c) is used to reveal ACTH- containing tumour cells by staining them yellow with an anti-ACTH antibody. By courtesy of Mr GM Rees and Prof I Doniach.