But considerable clinical evidence has been accumulated that one at least of the internal secretions, namely, that of the _thyroid_, has a definite beneficial effect upon cancer; this I have administered to many cancer patients, and have reason to believe that it contributed to the favorable results obtained. Sajous, believing that insufficiency of the adrenal secretion is an element in altered nutrition, advocates thyroid extract on the ground that it stimulates the activity of the adrenals: Vincent quotes Erlich as believing that “there may be substances circulating in the organism which may stimulate the body cells to resist the athreptic influence of cancer cells.” Shirlaw advises a tablet made of thyroid 6 grains, supra-renal ¾ grain, and pituitary 1/16 grain. While the treatment by these hormones from internal secretions is really in rather an experimental stage, it would seem more than probable that the correct use of these pluriglandular extracts, in combination with other proper dietary and medicinal treatment, would be of service in the prophylaxis and treatment of cancer. I have been a little cautious in the use of thyroid, beginning with two or three grains with meals, three times daily; for, as a promoter of catabolism it can disintegrate tissue faster than the emunctories can remove the effete products, and may thus poison the system. Serum- and Vaccine-therapy are yet in a stage of development, and as I have had little or no personal experience with them I will not attempt to discuss their value, which time alone will demonstrate. While there have been many claims of success from treatment along these lines, unfortunately they have not been confirmed by later observations by others: I may say frankly that they have never appealed to me as rational, in consideration of the views and experience I have long had along other lines of thought and practice. If, however, future investigations shall confirm some of the remarkable reports which have been made, the latest of which is by Nowell, there may be opened a non-surgical line of treatment of cancer which would mean much to many otherwise hopeless cases. The _local medical treatment_ of cancer is also an important matter which should receive careful attention. For many years in early cancer of the breast, under proper, general, dietetic, hygienic, and medicinal treatment, I have seen the lump vanish under the continued application of the iodide of lead, in Hebra’s diachylon ointment of the German Pharmacopœia (ʒss-ʒi ad ℥i), and in very many instances I have had the assurance of patients that its application relieved the pain and was of the greatest benefit also in axillary and other metastases. In other cases the continuous painting with ichthyol (50 p.c. in water) has seemed to be of great service, in combination with other proper treatment: all of this in earlier cases, before ulceration has occurred.