Fig. 4

Macroscopic and microscopic views of the resected lung. a Macroscopic view of the resected lung with dissemination (white arrowheads). b Hematoxylin and eosin staining of the adenocarcinoma, which included fibrotic change due to prior treatment with PBT and chemotherapy. Bar = 50 µm. c Macroscopic view of the resected bronchus with fistula (yellow arrowheads and circle). White arrowheads show the central side of the left upper bronchus with staples. Bar = 5 mm. PBT proton beam therapy