Fig. 2

Diagnostic images and pathological findings for case 2. a A CT scan shows a large tumor in the left lower lobe of the lung. b Preoperative PET-CT scan revealed no other lesions that could have represented a primary site. c Hematoxylin-eosin staining of the resected tumor, ×40 (scale bar, 100 μm). d Immunohistochemistry showed negative for PD-L1 staining, ×40 (scale bar, 100 μm). e Eight months after the pulmonary resection, PET-CT scan showed the uptake of fluorodeoxyglucose in the cecum