Morphometric analysis and immunohistochemical expression of cytochrome C oxidase in colonic adenomas and adenocarcinomas

Background/aim
Colorectal cancer is the seventh most common cancer in Egypt, constituting 3.47% of male cancers and 3% of female cancers. The aim of the current study is to evaluate the immunohistochemical expression of cytochrome oxidase (CcO) as well as the nuclear morphometric measurements in colonic adenomas and adenocarcinomas.
Materials and methods
Sixty cases of colonic biopsies/specimens were involved in this study. The samples were received in the Department of Pathology of Kasr El-Aini Hospital, Cairo University, Egypt, and they were divided into three groups: 20 cases of normal control, 20 cases of colonic adenoma, and 20 cases of colonic adenocarcinoma. The expression of CcO was studied by immunohistochemistry in 60 formalin-fixed paraffin blocks. Nuclear morphometric parameters were evaluated using an image analysis system. The area percentage of the marker expression was correlated with nuclear morphometric parameters.
Results
Immunohistochemical study showed that 65% of control biopsies showed a significant difference with colonic adenocarcinoma cases in contrast and adenoma cases showed a nonsignificant difference with normal control biopsies. Mean areas percentages of CcO expression were significantly different between all three studied groups. The means of nuclear area, length, and perimeter showed a significant difference while means nuclear width and roundness showed a nonsignificant difference between all three studied groups. There was significant correlation between mean area percentage of CcO expression with mean nuclear area and perimeter in control, adenoma, and adenocarcinoma cases.
Conclusion
CcO protein is significantly expressed in the cytoplasm of normal colonic mucosa. It was significantly deficient in colonic adenocarcinoma. Nuclear morphometry can be introduced as a useful morphologic feature of patients with variable colonic lesions specially in combination with CcO.