Cancer of the Breast
It seems to us that contact x-ray therapy, even with the increased kilovoltage which Dr. Griffiths suggests, must have a very limited scope in the treatment of breast cancer.
Abstract
SIR,-We feel that the letter of Dr. W. Griffiths (Journal, February 20, p. 416) is apt to be misleading to those inexperienced in radiation therapy. In advocating contact x-ray therapy we gather that he is referring solely to the treatment of cancer of the breast. He says "that the sole virtue of radium lies in our ability to place it in contact, or nearly so, with the growth.'" This applies perhaps to interstitial therapy, where the radium is actually introduced into the tissues in the immediate vicinity of the growth and so arranged that adequate "cross-fire " is obtained; but it certainly does not apply to surface radium applications. Ten years ago we were treating rodent ulcer and squamous-cell carcinoma of the skin with radium tubes in contact, and though early results were good, recurrence in the less superficial lesions was fairly common. During the past seven years the increased depth dose obtained by irradiating at a distance of 1 cm. (or more in deeply infiltrating lesions) has given uniformly excellent results from the points of view of primary healing and freedom from recurrence; incidentally intensive doses of x rays (100 kV with a 0.5 mm. aluminium filter at a distance of ten inches), administered over a period of a week or ten days, has given in the few cases in which we have tried it equally good results. In the treatment of such localized superficial conditions contact x-ray therapy may give comparable results. To return to the subject of cancer of the breast. The types of case with which the radiologist is called upon to deal are so varied that no single technique of irradiation can be universally applicable. Interstitial radium, highvoltage x rays with heavy filtration, and lower-voltage x rays with less filtration, all have their place. It seems to us that contact x-ray therapy, even with the increased kilovoltage which Dr. Griffiths suggests, must have a very limited scope in the treatment of breast cancer. Isolated skin nodules certainly might be successfully dealt with, but the rapid falling off of intensity at the edge of any but small skin fields inseparable from this " close-up " therapy would make it difficult to apply in those cases of extensive nodular skin recurrence, sometimes confluent and ulcerating, which are so commonly encountered. Assuming the desirability of lower voltage, why not an adequate distance? In dealing with the primary inoperable growth, glandular or bony metastases, the inadequate depth dose obtainable with contact therapy must surely rule it out.We are, etc., J. E. BANNEN.