Radiation biology.

Abstract

The Symposium on Radiation Biology presented at the Forty-fourth Annual Meeting of the Radiological Society of North America provided a broad and eclectic review of this rapidly evolving field for members of the radiological profession. The Symposium comprised two papers on radiation carcinogenesis and on late somatic effects of radiation, respectively, and four papers dealing with cell renewal and radiation injury, with possible additive or synergistic effects of combining chemotherapeutic agents with radiotherapy, and with the possible amelioration of radiation damage by one of the newer hormonal agents. The latter four papers appear in this issue of Radiology. A second symposium dealt with the hazards of radiation exposure in diagnostic roentgenology and the methods by which such exposure might be reduced.1 Such symposia can serve a most useful purpose by helping the radiologist keep abreast of developments in this sometimes bewildering field. Three different lines of investigation are generally subsumed under the heading “Radiation Biology”: (1) the possible hazards of diagnostic and other medical uses of radiation; (2) the mechanism by which radiation kills normal and malignant cells, and the modification of these effects; (3) the assessment, treatment, and prevention of somatic and genetic injury to whole populations due to radiation from nuclear weapons testing, civilian medical applications, and natural background sources. The first of these areas, to which the public at large has now been alerted by a number of reports (1, 2, 3), is of particular interest to the diagnostic radiologist; the second is obviously the concern of the therapeutic radiologist; and it is clearly the responsibility of all radiologists to be conversant with the third, inasmuch as the public and our medical colleagues look to members of our specialty for authoritative opinions on all questions in this area. The evaluation of possible hazards of small radiation doses in large populations is a tricky and difficult subject for investigation (4, 5, 6), and the radiologist must be alert to the statistical, dosimetric, and epidemiologic pitfalls with which it is beset. Our training has given us little preparation for dealing with these topics, and yet we are better prepared than the rest of our medical colleagues, who therefore look to us for help. Symposia which provide us with the timely, carefully considered views of experts in this branch of radiation biology may help us to fulfill this obligation. The enhancement of awareness, per se, among members of our profession regarding sources of unnecessary and possibly excessive radiation exposure in the course of diagnostic x-ray examinations has done much to provide solutions to the problem.