Acute Radiation Reactions Research Articles

Dose perturbation resulting from gold fillings in patients with head and neck cancers

Among patients who are being treated for head and neck cancers, those with gold-filled teeth have earlier acute radiation reactions in the lateral surface of the tongue and buccal mucosa adjacent to their gold fillings than patients with no gold filled teeth. An investigation to determine the cause of this reaction revealed a rapid increase in the dose adjacent to the metal teeth. This high dose zone was found to be less than 2 mm in tissue. This overdosage can be prevented by separating the gold-filled teeth from the oral mucosa with dental caps made of tissue equivalent material.

Ultrastructural Stereology of X-Irradiated Epidermis

Variations in the amount of several epidermal cell components during the process of radiation-induced acute cell death were studied following single local exposures of the tails of rats to a high dose of x radiation. The results were obtained by applying methods of ultrastructural stereology and expressed in relative and absolute volumes, surfaces, and numbers of the most important keratinocyte constituents. The increment of the nuclear volumes, the nuclear membrane surfaces the number of mitochondria, as well as an increase of the volume of filament bundles during the first 48 hr after radiation exposure, reveal an increased metabolic activity. Seventy-two hours after irradiation, this phase of cell hyperactivity is followed by a period in which the degradative phenomena become evident, i.e., an increasing mitochondrial swelling represented by an extreme increment in the volume of the average mitochondrion, the appearance of a significant amount of lipid droplets, and the cessation of protein accumulation in the form of cytoplasmic filaments. These statistically significant changes indicate that during the early stage of acute radiation reaction in the epidermis, the keratinocytes exhibit an increased activity which after 48 hr is surpassed by degenerative phenomena leading to ultimate cell death and skin ulceration.

Radiation enteritis in children.A retrospective review, clinicopathologic correlation, and dietary management

The clinicopathologic features of radiation enteritis are reviewed in 44 children receiving whole abdominal radiation therapy between 1961-1972 at the Institut Gustave-Roussy. Five of 14 long-term survivors (36%) developed severe delayed radiation injury with small bowel obstruction, occurring within 2 months after completion of irradiation. All had previously had acute radiation reaction during therapy. Histologic appearance in the small bowel at the time of delayed radiation injury revealed severe villus blunting, lymphatic dilatation, and moderately dense inflammatory infiltrate. All patients with delayed radiation injury showed marked clinical improvement coincident with a fractionated low-residue, low-fat diet, free of gluten and free of milk and milk products. The abnormal small bowel roentgenographs and small bowel biopsies reverted to a normal appearance in association with the diet. No exacerbation of radiation enteritis has been seen following dietary therapy.

Radiotherapeutic Principles and Viewpoints

Squamous cell carcinoma is an important and common cancer of the oral cavity and the lower lip. Although variable degrees of differentiation do occur, the predominant histopathological finding is in the direction of a moderate to a well-differeniated tumor. On the lower lip, in the oral cavity (in which the common location is the oral portion of the tongue), the floor of the mouth, and the lower gingiva (mandible), the squamous cell carcinoma is a radioresponsive and radiocurable neoplasm. The therapeutic armamentarium currently available for attack on these lesions is diverse; it includes radiations uniquely advantageous for obtaining control of these tumors. They range from low-voltage x-ray suitable for superficial lip carcinomas, to orthovoltage radiation for advanced lip lesions and per oral techniques, to supervoltage radiation; the latter minimizes acute and chronic cutaneous radiation reactions and, significantly, relatively spares the bone tissues. In addition, low-intensity radium needles or radioactive substitutes

EARLY OPERATION, A CONSERVATIVE APPROACH TO THE TREATMENT OF CHRONIC IRRADIATION INJURY

A survey is made of the treatment, especially by surgery, of 169 patients with dermatitis or ulcers resulting from radiotherapy. Complications of surgery occurred in 65 (39%) of the patients. The cases were reviewed in terms of: postoperative complications, stage of the disease, time interval from exposure to treatment, and method of treatment. Ranging from prolonged healing to massive fatal hemorrhage, the most common postsurgical problems appeared to be directly related to the diminished blood supply, lowered tissue vitality, and excessive fibrosis present in the radiologically damaged wounds. Clinical manifestations were divided into two major groups: radicdermatitis representing the earlier stage characterized by atrophy, telangiectasia, fibrosis, and keratosis but with an intact surface epithelium; and radiation ulcer with tissue breakdown, infection, and malignant degeneration. If therapy is instituted after the epithelial covering of the injured area is broken, the complication rate rises rapidly. Thls indicates that early surgical therapy is the procedure of choice. The highest incidence of postoperative difficulty occurred in those cases treated before one year after exposure. The early onset of clinical symptoms requiring surgical therapy represents an acute process resulting either from massive cancercidal dose, or abnormal sensitivity to radiation. This suggests that surgical therapy formore » an acute radiation reaction is extremely hazardous. The simplest methods of treatment produce the lowest percentage of postoperative difficulty. If however, these methods are re-evaluated in terms of the stage of the disease, the simpler surgical techniques are the procedures of choice before there is local tissue breakdown. But with advanced change, more complex methods of reconstruction are required and, despite their complexity and multiplicity of stages, pedicle reconstruction and block resection techniques carry a lower surgical complication rate. (H.H.D.)« less

The Suppression by Cortisone of the Acute Local Radiation Reaction in the Rabbit Ear

The action of cortisone on the response of the skin of the rabbit ear to a single x-ray exposure was investigated. Gross and microscopic studies were done after tissue doses of 1000 to 30,000 r. Doses of 1 to 20 Mg of cortisone per day parenterally (and 2.5% looal cortisone) were starte and then discontinued over a period of 2 days prior to irradiation to 90 days postirradiation. These studies confirm the finding that cortisone will suppress ulceration over a range of radiation dosage and demonstrate a remarkable suppression of inflammation after the initial degenerative changes, as long as the cortisone is continued. The results indicate that inflammation is secondary to degeneration of cells and is suppressed locally. (auth)

Osteomyelitis of the mandible following irradiation; an experimental study.

Osteomyelitis of the mandible following irradiation for the treatment of cancer has been recognized since 1922 (3). In spite of newer technics, including megavoltage (4), osteomyelitis is likely to remain a recurrent problem as long as portions of the mandible lie within the field of irradiation. It has been believed that the likelihood of this complication is decreased by the preliminary extraction of any teeth that are diseased or lie within the area to be irradiated. This opinion, however, has not been universal and experienced radiation therapists, such as Quick (2) and Paterson (1), have advocated postponement of extraction. More recently, Wildermuth and Cantril (5) have proposed that extraction of teeth before irradiation actually predisposes to osteomyelitis. We are reporting the results to date of a series of experiments designed to study certain features of this problem. Material Adult mongrel dogs were used throughout these experiments. They were housed in individual cages and were maintained on the standard kennel ration of cooked ground horse meat, rolled oats, fish oil, and tomato juice five days a week. On weekends, dry commercial dog ration reconstituted with water was substituted. Both diets were of a mushy consistency and required no chewing. This diet has been in use for many years and has been found to be nutritionally adequate. Preliminary examination of the mouth was performed to exclude animals with pre-existing dental or gingival injury or abnormality. Irradiation Technic X-rays of 250-kv with a half-value layer of 1.4 mm. Cu were used at 50 cm. target-skin distance. The output, which was calibrated daily, varied between 105 and 110 r (measured without back-scatter) per minute. Each side of the mandible was treated through a single lateral field measuring 5 × 5 cm. The anterior margin of the field coincided with the anterior margin of the fourth premolar and extended back onto the ramus of the mandible. The entire superior-inferior width of the mandible was encompassed by the field. A lead shield, 3 mm. thick, was placed on the lingual side of the mandible, protecting the tongue and the opposite side of the jaw. A second lead shield was used to demarcate the anterior margin of the irradiated area in addition to the treatment cone. The animals were irradiated every other day, three days a week, for an overall period of fifteen days. The right and left sides of the mandible were irradiated identically on each occasion. The total amount of radiation to each side ranged from 3,000 to 8,000 r, measured in air. First Experiment The first experiment was designed to determine whether osteomyelitis could be produced, and at what dose level, under the experimental conditions. Eight dogs were used. The total amount of radiation delivered ranged from 3,000 to 8,000 r (air) in 1,000 r increments. The acute radiation reaction observed corresponded to that seen clinically.

The Acute Radiation Syndrome

The radiologist has had unique preparation for appreciation of the effects of acute radiation on the human organism. In meeting the challenge of increasing civilian and military uses of atomic energy, as well as the possibilities of atomic warfare, he must be concerned with the details of the acute radiation syndrome and new information concerning it. Until recently, the major sources from which such knowledge was derived were small animal experiments, clinical radiological experience, and reports of the effects of the Hiroshima and Nagasaki explosions. Estimations of the response of human beings to whole-body radiation as obtained by extrapolation from clinical experience have proved to be entirely inadequate. The very large volume of radiobiological data from small animal experiments is not completely satisfactory as a basis for predicting human reactions. The Hiroshima and Nagasaki observations are complicated by incompleteness of data on radiation intensities, lack of objective clinical studies in the early stages, and the presence of superimposed thermal and mechanical injuries. Two recent publications have such particular interest with respect to acute radiation reactions that it seems appropriate to direct specific attention to them. The acute radiation syndrome is described in papers of Hempelmann (1) and Hempelmann, Lisco, and Hoffman (2), based on nine cases of accidental exposure at the Los Alamos Scientific Laboratory. The second of these papers is a comprehensive monograph published as a separate part of the February 1952 issue of the Annals of Internal Medicine. In it, the acute radiation syndrome is defined as “the group of signs and symptoms which characterize the illness produced by exposure to ionizing radiations of the entire body or a large part of the body.” It is to the credit of the health and safety operations at the Los Alamos Laboratory that only ten such unfortunate accidents occurred. It is fortunate that these cases were so carefully studied. The radiations consisted of moderately fast neutrons and hard gamma rays from temporarily uncontrolled fission reactions. They did not produce uniform radiation patterns throughout the bodies of the exposed persons, but the patterns are carefully analyzed and the physical corrections seem adequate for comparison with homogeneous whole-body exposures. The individual cases are presented with clinical completeness, exhaustive documentation and analysis of laboratory data, and interpretation with regard to the biological basis for the clinical responses. In the ten cases from which the nine reported are drawn, two individuals died as a result of the acute radiation injury; one other showed a typical acute radiation syndrome and recovered. Four others, who received lesser exposures, showed hematological reactions. These cases are unique, they are presented with great care, and they merit the close study of all radiologists.