[Clinical study on development factors of radiation pneumonitis].

Forty-six lung cancer patients received radiotherapy from 1982 to 1987 were reviewed to analyze the incidence of radiation pneumonitis and the factors which were related to it. The incidence of which evaluated with plain chest X-ray was 54% at 1 month, 78% at 3 months and 89% at 6 months after radiotherapy. The relationship between severity of pneumonitis and several parameters were studied. As a result, six parameters consisting of pre-radiotherapy granulocyte counts, tumor location, T-factor, radiation dose, radiation field size and the combination timing of chemotherapy were found to be contributing factors.