In the employment of the x-rays for the treatment of cancer, three methods have been advocated; first, the treatment by fractional doses; second, the employment of three or four large doses; and last, the application of one or two maximum doses.
In this country the first named method has been the usual one.5 A moderately hard tube is selected, and put at a distance of about four inches from the lesion. Exposures vary in time from ten to twenty minutes, and are given at intervals of two to four days, and continued until the lesion has disappeared, this sometimes requiring several months. It is necessary to produce a slight dermatitis, but not a severe burn. In many instances very excellent results have been obtained by it-results as good as those obtained in the later methods. As experienced and excellent an x-ray operator as Pusey still believes in it. At a recent symposium before the American Medical Association in the Section on Pharmacology and Therapeutics, Pusey* said: "I sympathize thoroughly with the scientific ideals which attempt to determine the limits of physiologic safety of Ront-gen ray exposures, but up to the present time I have been constrained to hesitate to adopt the maximum dose method in my own practice. I have done this for three reasons. First, I am sure that I have had my best results by a technic that consists of fractional doses-not of a few heavy applications. Certainly in my own experience the attempt at a radical quick dose has not proved as therapeutically efficient as several cumulative doses. In the second place, I cannot get away from the feeling that we are running a considerable amount of danger in the use of massive doses. We can make all of the factors the same except one, and that is the factor of the individual, the personal equation of the patient. At any rate, I do not feel that one patient will react just as the next one will. If I can draw any conclusion from my experience, it is that there is a difference of susceptibility in patients. In the third place, to give a massive dose requires attention to a group of important factors, and I think that in routine work the danger of some error is not to be overlooked. As a matter of fact, I have been consulted today about a burn following a massive dose of Rontgen rays for destroying ring worm, so that the idea of danger is not purely a theory. As for my technic, I give repeated doses of Bojitgen rays until I produce my effect".
*Pusey: Principles and Practice of Dermatology, Phila., 1907. Pusey and Caldwell: The Rontgen Rays in Therapeutics and Diagnosis, New York, 1904.
*Pusey: Jour. Amer. Med. Assn., 1913, lxi, 698.
In such a method as this there are several necessities. The operator must thoroughly understand the capabilities of both his machine and tube; at first he must proceed carefully until he tests these instruments out upon each particular patient, and then he can give numerous sittings. The work is prolonged and necessarily rather expensive, and the patients often tire of it. Of course, it is absolutely essential that all of the surrounding skin be covered with lead foil, so that neither an acute burn nor atrophy and telangiectases can follow.
It was soon found that two exposures of twenty minutes each, using the same tube and the same amount of current, were just as effective as nine or ten exposures of five minutes each, provided that the former were not too long separated. These figures are, of course, merely given in round numbers-as illustrations and not as absolute facts. As a result, many men began treatment along these lines,* and in general the results were just as good as by the older method. There has been a marked shortening in the duration of the treatment, and not as much liability to atrophy and telangiectasis, but some danger of an acute burn. The use of the penetrometer to measure the quality of the rays and of the Sabouraud-Noire pastille to measure the quantity of the emanations has markedly lessened this danger, but it is still present, especially with the inexperienced operator.
The natural sequence of this treatment was to give one, or perhaps two, massive doses-doses measured accurately both as to quantity and quality. In America MacKee, of New York, has been the chief exponent of this idea, although, as he points out, the method is in common use abroad, and his results have been excellent (Figs. 69, 70). The following account is derived from his various papers on the subject, and from my own personal experience, which is identical with MacKee's.
MacKee and Remer* claim that an accurate measurement of the dose is as important in Rontgen ray therapy as in any field of medicine ; that the massive dose, carefully measured, is both accurate and scientific; that the patient is spared the necessity of many visits to the physician's office; and last, that this form of treatment is better therapeutically. In explaining the last point, they say: "Several years ago it was customary to apply the x-ray to epithelioma in very small doses three times a week. It was not uncommon to hear of 30 to 150 or more treatments being given to one patient. Those who are familiar with past results will recollect that a certain percentage of the patients were permanently cured, while in an unfortunately large proportion recurrences were common. It will also be recalled that the recurrences were not only resistant to further x-ray treatment, but that in many instances the lesions failed to respond at all, and even became so malignant that they could not be controlled at all. There were instances, too, where the primary epithelioma underwent involution to a certain point, and, after remaining quiescent for a time, began to assume malignant tendencies while under the influence of the ray.
*Lango: Jour. Amer. Med. Assn., 1913, lxi, 556.
*MacKee and Remer: New York Med. Jour., March 29, 1913.
*Amer. Jour. Rontgenology, Dec, 1913.