Figure 1.

In patient 1, a 54-year-old man with advanced melanoma received a trial of anti-PD-1 treatment with pembrolizumab combined with radiotherapy. Before anti-PD-1 treatment, chest radiograph (CXR) and computed tomography (CT) revealed pulmonary lesions over bilateral hilums (A and B). After 4 cycles of anti-PD-1 treatment, the findings significantly progressed and air-bronchograms at right lower lobe with obstructive pneumonitis was found (C and D). CT = computed tomography, CXR = chest radiograph, PD-1 = programmed cell death protein 1.