Recommended control tissue: Pituitary gland
Confirmation of ACTH-production. Diagnosis of ACTH-producing pituitary tumors.
Metastatic bone tumor. Clinically, ACTH-producing tumor was supected. Immunohistochemistry for ACTH cleary demostrated ACTH-positive. Background staining is result of “diffusion” phenomenon.
Note: ACTH-positive on IHC is not equal to functioning tumor.