The _supra-renal_ glands by their secretion have, as we know, great vaso-constrictor influence, and their complete removal is followed by death; it is more than possible that some failure in this secretion allows the exuberant blood to supply cancerous growths. Sajous says: “Certain growths, particularly the more malignant forms of sarcoma and carcinoma, seem closely connected with adrenal insufficiency and its normal consequences,” and there have been some clinical and research data confirming such a conclusion. Sajous further says, “The adrenals, as supporters of the thyroid apparatus in the defensive process, and in sustaining oxidation, metabolism, and nutrition, seem to offer a new clew to the pathogenesis and treatment of cancer that is worthy of further inquiry.” The _pancreas_ has been thought to have some influence in a perverted metabolism leading to cancer, Kahle stating that there is a retention of silica in that organ in cancer patients, to even double the normal amount. A treatment of cancer introduced by Beard, also strongly presented by Saleeby, by trypsin and amylopsin, the enzymes of the pancreatic fluid, excited some attention a while ago; but unfortunately no satisfactory results have thus far been obtained from this line of medication, as was fully demonstrated by Bainbridge at the New York Skin and Cancer Hospital, in one hundred cases. The _pituitary gland_ by its secretion has undoubtedly some coordinating power, with the adrenals and thyroid, over the processes of metabolism, and a number of observers have regarded it as of importance in connection with the genesis of cancer. Little has recently reported some cases of cancer in which _pituitary extract_ with that of the pancreas has produced remarkable results. The _thyroid_ is now recognized as playing an important part in assisting metabolism, and, like the adrenals and pituitary, its complete removal, with the parathyroids, in animals is followed by death. While the study of the hormones is still in its infancy, there seems to be no question but that the endocrinous glands act conjointly, the one influencing the other, and that together they exert a very great influence in the life processes of the body and on the behavior of its component cells. The thyroid has been shown to be one of the main factors in the management of calcium within the body, which is believed to be an element in cancer, and enhances the catabolism of toxic wastes, which are etiologic elements in this disease. Many have reported favorably on the effect of thyroid feeding in cancer, and after an experience with it in many cases I am convinced that it has been one of the means which contributed to the good results obtained. On the other hand it has been claimed by Stuart-Low that the surgical removal of the thyroid, or part of it, or ligation of the thyroid blood vessels has arrested cancer, in several cases.