Side-Effects of Combined Radiation and Chemotherapy in the Treatment of Malignant Tumors

Abstract

In a review of 99 cases of advanced solid tumors treated by a combination of irradiation and chemotherapy, it became apparent that toxic reactions capable of altering proposed treatment plans, even to requiring hospitalization, were frequent. Such reactions assume great importance in evaluating the response of any treatment technic. A high incidence of severe side-reactions, dangerous and debilitating to the patient, could well discourage therapy programs which produce only slightly better statistical improvement in the treatment of disease. In using therapeutic modalities in combination, the side-effects of each may become intensified. Great care must be taken not just in the treatment of these side-effects, but also in their anticipation. The patient must be questioned daily concerning minor symptoms in an effort to intercept and prevent the onset of major toxic reactions. In our series we have used predominantly 5-FU in combination with radiation. In a few cases, Actinomycin D, Mitomycin C, and chlorambucil were employed. All are hematopoietic depressants. All are capable of producing gastrointestinal symptoms—nausea, vomiting, and diarrhea. The commonly seen side-effects in our series were anorexia, nausea, occasional vomiting, mild diarrhea, and, at times, skin reactions. These were seen frequently and, when mild, are usually easy to control on an outpatient basis. The more severe reactions, i.e., uncontrollable vomiting and∕or diarrhea, electrolyte imbalance, bullous erythema multiforme, and exfoliative dermatitis, require prompt hospitalization for adequate correction. It becomes important, then, to realize the need of available beds for patients undergoing intensive combined drug and radiation therapy. Side-effects which usually necessitate the interruption of the combined treatment are severe gastrointestinal symptoms, a drop in the white blood count below 2,000, and a fall in the hemoglobin level below 10 gm. Prolonged therapy interruption can alter the eventual effectiveness of the treatment and thus diminish the possibility of a therapeutic response. With the treatment plan used in our series, a high incidence of definite signs of toxicity was seen (Table I). In 77 of all the cases at least one definite sign was evidenced. Thirty-three patients required a break in the continuity of the radiation therapy, and 12 needed hospitalization for intensive treatment of toxicity. Death in 6 was directly due to toxic reactions and massive infection. Table II evaluates the relationship of the amount of drug and the time of direct injection of the drug to the occurrence of toxic reactions in 47 cases of lung cancer. The simultaneous administration of 5-FU loading with radiation therapy seems to be more hazardous than preloading with 5-FU.