My theories of cancer, its origin and nature, differ toto caelo from those advanced by any other observer, living or dead. The theory of the germinal origin of cancer, which says that a cancer arises primarily from a latent germ-cell, does not mean that cancer is embryonic in origin or character. Germ-cells, such as fertilized eggs, give rise to something else than embryo or soma they produce on occasion trophoblast (asexual generation). I know that some embryologists, for whom chemistry and physiology have no existence in their researches, describe the trophoblast of Hubrecht as merely another name for what they term “extra-embryonic epiblast.” To use the latter term does not signify anything more than where in normal development the supposed portion of epiblast lies—i.e., beyond the embryo. I do not agree with them that trophoblast is epiblastic (embryonic skin) in character, or that their description of it as “extra-embryonic epiblast “ in any way defines it embryologically. Their account is merely descriptive, and it gives no information whatever concerning the chemical, physical, or physiological characters of this “extra-embryonic epiblast” or trophoblast, which, quite unlike ordinary epiblast or embryonic skin, eats and erodes the maternal tissues.
In very simple words I will now endeavour to summarize what is meant by the germinal origin and the asexual or trophoblastic nature of cancer. To these shall be added brief accounts of the reasons advanced six years ago for employing ”the secretion of that important digestive gland, the pancreas,” including the two ferments, trypsin and amylopsin, in the scientific treatment of cancer. It is appropriate that this should be written down on January 20, 1911; the sixth anniversary of the scientific lecture in Liverpool, in which the more important of these reasons were first announced publicly.