Limited small cell lung cancer treated by combined radiotherapy and chemotherapy: evaluation of a grading system of lung fibrosis.

A grading system of radiological fibrosis was defined and applied by four observers for the reading of 218 posterior-anterior chest X-rays of 78 patients. These patients with limited small cell lung cancer were treated from May 1980 to July 1983 in two consecutive alternating radiotherapy-chemotherapy schedules. Chest X-rays performed at each 6-month interval were read by each observer. A second reading was performed the day after. The analysis of results showed that in spite of some systematic variations in intra- and inter-observations, the proposed grading system had a good reproducibility. The radiological lung fibrosis score progressed between 6 and 12 months but was stable after one year of follow-up. There was no difference in the score of lung fibrosis between the two protocols which delivered a total dose of 45 and 55 Gy to the mediastinum. There was no significant correlation between the radiological changes and clinical symptoms.