Fig. 4
a Bronchoscopic biopsy specimen from the right lower showing poorly differentiated non-small-cell lung cancer, specifically squamous cell carcinoma (hematoxylin-eosin, original magnification × 200). b Immunohistochemistry revealed that the tumor cells were positive for p40 and p63 expression. Immunohistochemically defining the tumor as a squamous cell carcinoma (× 200)