Fig. 1

Radiological and histopathological findings. a A chest radiograph showing a mass in the right upper lung field. b A chest computed tomography scan showing a mass with an irregular surface in the right upper lobe. c Gross examination showing a solid tumor (diameter, 5 cm) with internal bleeding. d-g Topographic presentation of the cut surface shows three different components; portion A: well-differentiated adenocarcinoma (e), portion B: poorly differentiated adenocarcinoma (f), and portion C: sarcomatoid cancer (g). The ratio of the area occupied by these 3 components, i.e. well-differentiated adenocarcinoma: poorly differentiated adenocarcinoma: sarcomatoid cancer, is 15: 80: 5. Yellow, light blue and red denote the area of well-differentiated adenocarcinoma, poorly differentiated adenocarcinoma, and sarcomatoid cancer, respectively