A Preliminary Report on Continuous Irradiation of the Entire Body

THE purpose of this paper is to present a new method of X-ray therapy consisting of continuous irradiation of the entire body at long distances from the tube. The following considerations have led the writer to the belief that this method may prove valuable in the treatment of certain types of neoplastic diseases: 1. As stated in the law of Bergonié and Tribondeau (1), “Immature cells and cells in an active state of division are more sensitive to the X-rays than are cells which have already acquired their fixed adult morphologic and physiologic characters.” A corollary of this law is that treatment should extend over a period sufficiently long to include the various times of mitosis of all the cells of the tumor. Under these conditions, it is supposed that, although a low intensity of radiation is necessitated by the long treatment, the dose received by the cancer cell at the time when it is most sensitive nevertheless is sufficient to destrov it or arrest its growth. 2. Dr. Ewing (2), in his Caldwell Lecture, states: “It is no longer possible to maintain that the body furnishes no aid in radiation therapy … Effective irradiation excites a favorable reaction on the part of the body as a whole. The nature of this reaction is complex and the factors are largely unknown. It is probably of much importance in the cure of malignant tumors by radiation.” He further states, “The immediate improvement in health and strength in leukemic subjects following irradiation suggests some such action.” The biologic work of Kok and Vorlaender (3) and of Caspari (4) shows the importance of generalized body irradiation in that a considerably smaller part of a skin erythema dose is required to cause tumor regression than is necessary for equal regression of tumors treated locally. Similarly, the work of Murphy and Nakahara (5) shows that irradiation of the entire body of cancer mice stimulates a defense mechanism against cancer invasion. 3. Physical considerations demand as an ideal the most uniform distribution of radiation throughout the tissues undergoing treatment. Uniformity of distribution is necessary in order to take full advantage of the relative radiosensitivity of normal and neoplastic tissues. 4. Certain types of neoplastic diseases, which tend to become widely disseminated early in their course, cannot be controlled effectively by the usual local treatments. Since the early stages of such dissemination are often unrecognizable, and since the earliest possible treatment of metastases offers the best chance for their control, it appears that the greatest hope of success in treating these tases lies in the irradiation of the entire body. A practical method of treatment, based on the above considerations, involves the prolonged irradiation of the whole body with very hard X-rays at long target-skin distances.