Cancer-Associated Lymphatic and  Venous Vessels in Colonic  Carcinomas

Tatsuo Tomita

doi:10.4236/ojpathology.2014.43016

Abstract

Objective: Colonic carcinomas spread to regional lymph nodes and liver. There are cancer-associated lymphatic and venous vessels at the margin of colonic carcinomas, which facilitate spreading carcinoma through lymphatic and venous vessels. This study aimed to examine cancer-associated lymphatic and venous vessels in TNM T1 to T3 carcinomas using lymphatic vessel hyaluronan receptor for lymphatic vessels and von Willebrand factor for venous vessels by immunocytochemical staining. Materials and Methods: A total of 40 cases of moderately differentiated colonic carcinoma were studied using routinely formalin-fixed and paraffin-embedded sections. The cases consisted of 10 cases of TNM T1, 15 cases each of T2 and T3 cases. Immunocytochemical staining was performed using goat antihuman LYVE-1for lymphatic vessels and rabbit antihuman von Willebrand factor for venous vessels. Results: In TNM T1 carcinoma, increased, irregular and narrow lymphatic and venous vessels were present in the adjacent normal mucosa to the carcinoma, some of which penetrated cancerous lesion. There were no tumor emboli in lymphatic and venous vessels. In TNM T2 carcinoma, there were few lymphatic and venous vessels in midst of the carcinoma whereas numerous small lymphatic and venous vessels were present within muscle layers adjacent to the invading carcinoma. Extramural tumor embolus was present in submucosa in one case. In TNM T3 carcinoma, cancer has invaded through the muscle layers where dilated lymphatic and venous vessels were present adjacent to cancerous nests. Tumor emboli were identified in two cases by immunocytochemical staining. Conclusion: The current study showed cancer-associated lymphatic and venous vessels at the interface in TNM T1 carcinoma to dilated intramuscular lymphatic and venous vessels adjacent to invading cancerous nests in TNM T3 carcinoma, and supports cancerous cells spread via lymphatic and venous vessels through muscle layers to subserosa as supported by tumor emboli in the lymphovascular system.

Highlights

The most common sites of metastasis of colonic carcinoma are regional lymph nodes and liver [1]
There is an agreement on the evidence that more lymphatic and venous vessels are present at the margins of colonic carcinoma, suggesting that colonic carcinoma spreads to regional lymph nodes through lymphatic vessels [1]-[5] and to liver by hematogenous spread [8] [9]
In the parallel cut sections along the Colonic cancer spreads predominantly to regional lymph nodes through lymphatic vessels little is known about cancer-associated lymphangiogenesis [15] [16]

Summary

Introduction

The most common sites of metastasis of colonic carcinoma are regional lymph nodes and liver [1]. Since cancer cells metastasize to regional lymph nodes through lymphatic vessels and to liver through venous vessels, lymphatic and venous vessel tumor invasion is the histopathological risk factor for colorectal carcinoma [6]. It is not easy to definitely identify and evaluate lymphatic vessel invasion by routine H. and E. sections, and immunocytochemical identification for the lymphatic vessel is a currently available tool for identifying lymphatic vessels [7]. Cancer-associated lymphangiogenesis has been a controversial issue [3]-[5] partly due to a lack of specific and reliable immunocytochemical markers for lymphatic endothelium [10]-[12] and a lack of universally accepted methodology to identify and evaluate lymphatic vessels in surgically resected colonic cancer specimens

Methods

Results

Conclusion