The use of special stains in the detection of vascular invasion in cases of colon cancer in resource-limited settings in Africa

Abstract

Background: Vascular invasion (VI) is a well-established independent prognostic factor in colorectal cancer (CRC) associated with the hematogenous spread and high risk of mortality. Its accurate detection is essential in identifying a high-risk group of patients who may benefit from adjuvant therapy and also to detect the risk of disease recurrence. The aim of the study was to determine the value of an elastic tissue stain in assessing vascular invasion in CRC. Materials and Methods: Formalin-fixed paraffin-embedded histologically confirmed CRC blocks were retrieved from the archives of the Histopathology Department of the Komfo Anokye Teaching Hospital. Duplicate sections were made from each block and divided into two, with one part of the sections stained with hematoxylin and eosin (H and E) and the other with Verhoeff–Van Gieson (VVG) stain. Both H and E and VVG-stained sections were assessed for vascular invasion. Findings were put in tables and charts. Results: Forty-one cases were used for our study, comprising 40 adenocarcinomas (six well differentiated, 26 moderately differentiated, and eight poorly differentiated) and one high-grade non-Hodgkin large cell lymphoma. The mean age of our patient was 55 years, with a male-to-female ratio of 1:1.4. Of the 41 sections stained with H and E, venous invasion (VI) was detected in 14 cases (34%), whereas VVG was detected vascular invasion in 18 cases of the 27 undetected by H and E in addition to all the 14 cases detected by H and E (78%). Conclusion: The application of the VVG elastic tissue stain enhanced the sensitivity of detecting VI as compared to the use of H and E alone, and thus, recommendations should be made to include elastic tissue stains in CRC pathology reporting to bring therapeutic benefits to patients in our environment.