Radiotherapy and pulmonary fibrosis

Clinical findings of radiation pneumonitis and pulmonary fibrosis were outlined, and the relationship between occurence of these disorders and radiotherapy, clinical findings and X-ray picture were studied. Standard radiation dose as cell lethal response of carcinoma of the lung were 4,500 to 5,500 rad in 4 to 5.5 weeks in undifferentiated carcinoma, 6,000 to 7,000 rad in 6 to 7 weeks in squamous cell carcinoma, 7,000 to 9,000 rad in 7 to 9 weeks in adenocarcinoma, 4,500 to 5,000 rad in 4 to 5 weeks in the large sized cancer of the esophagus, 6,500 to 7,000 rad in 5 to 7 weeks in the small sized cancer of the esophagus, and irradiation of these amount of dose caused hazards in pulmonary function. Pathological and clinical findings of pulmonary hazards within 6 month period after irradiation, factors causing them and changes in X-ray pictures before and after irradiation were observed and discussed in clinical cases: the case of breast cancer in which 3,000 R/6 times/18 days of 5.5 MeV Liniac electron was irradiated to the chest wall, and the case of pulmonary cancer in which 5,000 rad/25 times/34 days of 6 MeV Liniac X-ray was irradiated in opposite 2 ports radiation beam treatment. The former revealed alveolar lesion and interlobular pleuritis at 4 month later, and remarkable lesion of pulmonary fibrosis was followed at 9 month after radiotherapy. The later developed radiation pneumonitis 1 month after radiotherapy, of which lesion extended to the upper part by 3 months later, and cancer recurred 6.5 month later. (Kanao, N.)