Figure 9a. Tumor embolism from cholangiocarcinoma in a 62-year-old man. (a) Thin-section (1.5-mm collimation) CT scan obtained at the level of the basal segmental bronchi shows a pleura-based, wedge-shaped area of high attenuation (large arrows) and numerous nodules, some of which demonstrate tree-in-bud appearance (small arrows). (b) Photomicrograph (original magnification, x12; hematoxylin-eosin [H-E] stain) of the biopsy specimen obtained at video-assisted thoracoscopic surgery demonstrates endovascular tumor emboli (thin arrow) surrounded by infarcted lung tissue (thick arrows). (Case courtesy of Eun-Young Kang, MD, Korea University Guro Hospital, Seoul, Korea.)