Histopathological results from CT‐guided puncture of the pneumonic lesion suggested poorly differentiated NSCLC with massive necrosis, indicating PSC with IHC markers AE1/AE3 (+), vimentin (+), P40 (−), TTF‐1 (−), S‐100 (−), SMA (−), desmin (−), and Ki‐67 (20%+). This evidence concerns the gene TTF1 and non-small cell lung carcinoma.