Immunohistochemical expression of CD163 in colorectal carcinoma and its prognostic value

Abstract

Background/aim Colorectal cancer (CRC) is one of the most frequent cancers worldwide with one of the highest mortality rate. CD163 is a 130-KDa transmembrane protein, known to be involved in hemoglobin clearance by functioning as a receptor for hemoglobin–haptoglobin complex. Several studies have demonstrated that CD163 is expressed on some cancer cells, and its expression is associated with poor clinical prognosis. This study aimed to evaluate CD163 to assess the distribution of macrophages in invasive margins and intratumoral infiltration area, using computerized image analysis, to evaluate its prognostic value and its association with other clinicopathological characteristics in colorectal carcinoma. Patients and methods The present study enrolled 80 formalin-fixed paraffin-embedded CRC surgical specimens, obtained from the Department of Pathology of National Research Centre, Egypt, and examined for the expression of CD163 in CRCs by immunohistochemical techniques. The morphometric analysis was done on the invasive margins and intratumoral infiltration area in each slide. Results The study cases of colorectal carcinoma patients, 46 (57.5%) cases were diagnosed as adenocarcinoma and rest 34 (42.5%) cases were mucinous carcinoma. Twenty-two cases (22/80) showed a low intratumoral infiltration area and moderate invasive margin. CD163+ intratumoral infiltration significantly correlated with age, tumor site, tumor type, lymph node status, and metastasis. On the other hand, CD163+ invasive margins significantly correlated with tumor grade, tumor classification, metastatic status, tumor stage, and Duke’s classification. Conclusion Invasive front of the tumor is the most suitable area for the evaluation of tumor-associated macrophages that is important in detecting prognostic prediction of colon cancer and its clinical outcome. So, it can be considered as an ideal prognostic marker in the treatment of colon cancer.

Keywords

• cd163
• colorectal carcinoma
• intratumoral infiltration
• invasive margins