GFAP and neoplasm: The histologic and immunohistochemistry analysis of the biopsy specimens from the lungs and mediastinal lymph nodes (Figure 2D,G), obtained via endobronchial ultrasound, showed that the tumor cell morphology was similar to that of glioblastoma; the tumor was positive for S100 and glial fibrillary acidic protein (GFAP) (effective markers of glioma; Figure 2E,F) and negative for thyroid transcription factor‐1 (TTF1) and P40 (markers of primary lung tumor).