Metastasis in a transplantable mammotrophic pituitary tumor.

Two strains of a mammotrophic pituitary tumor were compared; the secretion of adrenocorticotropic hormone had declined appreciably in one and, in the other, was un changed. The secretion of adrenocorticotropic hormone by the pituitary tumor does not appear to be related to the capacity for metastasis inasmuch as metastasis was ob served in the retroperitoneal lymph nodes of animals bearing both types of tumor. The microscopic picture as well as ultrastructure of the métastaseswere identical to that of the primary tumor. Métastaseswere not observed grossly or microscopically in any other organs. The size of the altered tumor was considerably larger than that of the unchanged one. The adrenal glands were significantly smaller in animals bearing the altered tumor, compared with those from animals bearing the unchanged tumor.