AIMS: UK faecal occult blood test screening has tripled the proportion of @entity2558 @entity14 . The risk of @entity3 is predicted by depth of invasion, suggesting that access to deep lymphovascular vessels is important. The aim of this study was to quantify the distribution and size of the submucosal vasculature, and generate a novel three-dimensional (3D) model to validate the findings. METHODS AND RESULTS: Thirty samples of normal large bowel wall were immunostained with @entity2279 , a vascular endothelium marker, to identify blood vessels, which were quantified and digitally analysed for their number, circumference, area and diameter in the deep mucosa and submucosa ( @entity895 , @entity3578 , and Sm3). The model required serial sections, a double immunostain (using @entity2279 and D2-40), and 3D reconstruction. Significant differences were shown between submucosal layers in the number, circumference and area of vessels (P  <  0.001). Blood vessels were most numerous in the mucosa (11.79 vessels/0.2  mm(2) ) but smaller [median area of 247   m(2) , interquartile range (IQR) 162-373   m(2) ] than in @entity3578 , where they were fewer in number (6.92 vessels/0.2  mm(2) ) but considerably larger (2086   m(2) , IQR 1007-4784   m(2) ). The 3D model generated novel observations on lymphovascular structures. CONCLUSIONS: The number and size of blood vessels do not increase with depth of submucosa, as hypothesized. The distribution of vessels suggests that we should investigate the area or volume of submucosal invasion rather than the depth.

New insights into the lymphovascular microanatomy of the colon and the risk of metastases in @entity2558 XXXX obtained with quantitative methods and three-dimensional digital reconstruction.

@entity3578 :: ('53366', 'Gene') :: ['Sm2'] @entity2558 :: ('58492', 'Gene') :: ['pT1'] @entity895 :: ('7911', 'Gene') :: ['Sm1'] @entity2279 :: ('5175', 'Gene') :: ['CD31'] @entity3 :: ('MESH:D009362', 'Disease') :: ['metastasis'] @entity14 :: ('MESH:D015179', 'Disease') :: ['colorectal cancers']
@entity14 :: (MESH:D015179,Disease) :: ['colorectal cancer']
