Cancer has long been a problem over which master minds have wrestled, and to read much that is written it would seem that we were yet as far from its solution as ever. Countless able men, at the expense of millions of dollars, have labored faithfully in the laboratory, and it may safely be said that more effort and time have been expended in investigations on cancer, and more has been written concerning it, than ever in connection with any other disease affecting humanity. And yet its mortality is steadily increasing pitifully, in spite also of active, skilful, and faithful surgical treatment. Is it not possible, therefore, that there is something wrong in our conception of cancer and its treatment? If any other disease presented such a steady and alarming increase in its death rate would we not stop and consider if our treatment were the best possible? If with the introduction of antitoxin the mortality from diphtheria had steadily risen until it was about 90 per cent of all cases, would we persist in employing it? And yet the profession and the laity go blindly on, with the idea that surgery offers the only hope of reaching cancer, when the Mortality Statistics of the United States show that under this line of treatment the death rate has _risen steadily_ from 63 per 100,000 of the population in 1900 to 81.1 per 100,000 in 1915, or 28.7 per cent. Surely the lesson taught by the steadily and greatly _decreased death rate_ of tuberculosis should teach us something of the value of most careful dietary, hygienic, and medical control of other diseases. For the great white plague, which a while ago threatened even the destruction of the race, shows now a mortality which has steadily _fallen_ 27.8 per cent since 1900, and that even with the continued presence of the tubercle bacilli. I realize that the comparison is not quite correct in all respects, for it is well established that cancer is not due to a microörganism; but it does show us that nutritive errors are at the bottom of the ravages of tuberculosis, and efficient biochemical studies in cancer have satisfied many that the same, although different in character, are true of this disease. In other words, erroneous nutrition, which is productive of disease of the kidneys, heart, and blood vessels, with their steadily rising mortality of ten to twenty per cent since 1900, as shown on the chart before you,[3] is operating to steadily increase also the morbidity and mortality of cancer, in spite of active and intelligent surgical treatment. And yet the profession and laity seem to be blind to this fact. It is also not a little remarkable that during the year 1915, when there was a special effort made to educate both the laity and the medical profession in regard to the advisability or necessity of early operations in cancer, the actual death rate rose by 1.7 persons per 100,000 living, whereas the average yearly rise for the preceding five years had been only 1.2 persons per 100,000!