Pulmonary reaction to radiation as seen on chest X-ray following megavolt therapy for carcinoma of the breast

The report evaluates radiographs of the chests of 184 patients treated for cancer of the breast in the period 1974 to 1978. The radiographs have been taken during radiotherapy and routine follow-up examinations and are studied with regard to the radiomorphological substrate, the intensity, and the time-related development of pulmonary radiation reaction following standardised extended-field irradiation (5-field technique) with a 4 MeV linear accelerator and focal doses between 50 and 60 Gy, with usual fractionation. After the characteristical latency period without any radiomorphological reaction, first signs of the onset of pneumonitis (stage I) are found in the radiographs after 11-13 weeks on the avarage, depending on the distribution in the lung parenchyma. Florid pneumonitis of stage II A is revealed by the radiographs after 14-19 weeks, and after 16-21 weeks the findings indicate florid pneumonitis and the onset of pulmonary cirrhosis (stage II B). The pulmonary radiation reaction then proceeds into a transitional stage III, and ends with stationary, regional lung fibrosis (stage IV). Classifying the intensity of the radiation reaction into three different severity groups, twenty of the cases observed, or 39 p.c., can be assigned to the group of 'slight' regional pneumonitis of fibrosis; another five cases, or 6 p.c., are of 'medium' severity, and twelve, or 4 p.c., belong to the group of serious reactions. During the period of florid pneumonitis, clinical symptoms such as pain in the thoracic wall, coughing, and febrile condition are reported for 21, 11 cases, or 2 p.c. (orig./MG)