Radiographic findings after stereotactic radiotherapy for lung carcinoma: retrospective analysis of 90 patients

Several radiological findings have been described after stereotactic body radiation therapy (SBRT) for lung tumors, corresponding to radiation induced lung toxicity (RILT). This retrospective study of 90 patients with a stage I non-small cell lung carcinoma reports a detailed description of the scanographic changes that can be observed after SBRT. A successive analysis of the radiologic changes according to modified Kimura scoring system for radiation pneumonitis (RP) and according to Koenig’s classification for lung fibrosis (LF), including the time of onset, the delay between irradiation and maximum extension, and the evolution of radiation pneumonitis (disappearance or persistence as a fibrosis) has been performed. The mean time of RILT appearance after SBRT completion was 4 months, reached its maximum extension at a mean time of 9 months, and the appearance of fibrosis occurred at a mean time of 11 months. Progression from RP to LF has been observed in 37 patients of 51 (73 %). RP complete resolution was observed in 7 patients of 51 (14 %). However, 13 patients developed fibrosis without a previewed RP. The most common radiographic radiation pneumonitis finding was a diffuse consolidation. The most extensive RILT was surrounded by the 35 Gy which probably reflects the role of high doses in this complication. Tumoral size evolution was not significantly different between the baseline and the last follow-up CT. Thus, follow-up using RECIST seems unsuitable.
Source: European Respiratory Journal - Category: Respiratory Medicine Authors: Tags: Lung Cancer Source Type: research