Gross and microscopic examination of the resected specimen. (A) On gross examination, the cut surface revealed a centrally cavity-formed, relatively poorly-demarcated, and solid firm mass, measuring 35 x 27 x 25 mm, which looked from grayish to whitish in color, partially adjacent to the bronchiole (lower side, inset). This central cavity measured approximately 30 x 10 mm, but filled with no necrobiotic materials. Bar = 10 mm. (B) A scanning magnification of it (H&E stains) showed that the cancer components were surrounded by the cavity and irregularly grew up along the asymmetrically thickened but relatively thin cavity wall, together with extension to the peripheral alveolar wall in a sheet-like fashion (lt. side). This tumor lesion was partly adjacent to the bronchiolo-vascular bundle (rt. lower side). There were no carcinoma in situ components in our case. Bar = 5 mm.
Yamada et al. Diagnostic Pathology 2012 7:175 doi:10.1186/1746-1596-7-175