Figure 16b. Recurrent tumor in a 60-year-old woman with limited small cell carcinoma. (a) CT scan obtained 27 months after completion of radiation therapy shows radiation fibrosis in the right upper lobe. Note the patent air bronchogram. (b) Fused CT-PET scan shows increased FDG uptake in the area of fibrosis. Note that the recurrent tumor does not fill in the air bronchogram.