Histological examination of the primo-vascular system in lung cancer xenografts.

<p>(A) Shown are a representative hematoxylin and eosin (H&E)-stained primo-node cross-section (top) and a Masson's trichrome (MT)-stained adjacent-section (bottom). Right figures are enlarged images of left figures. (B) Depicted are primo-vessel cross-sections which were stained with H&E (left) and MT (right). (C) H&E staining of an oblique section containing both a primo-node (a double arrow) and a primo-vessel (a dotted arrow). An image of the primo-node was magnified in the right figure. There are multi lumens (arrows) with floating cells (arrowheads) in all samples which are distinct from a single lumen structure of lymph or blood vessels. Furthermore, MT staining revealed primo-vascular system consists of loose collagen fibers (blue color) surrounding lumens.