HISTOPATHOLOGICALEVALUATION OF COLORECTAL CARCINOMA

Abstract

Background: Colorectal cancer is the most common gastrointestinal tract cancer worldwide. In Iraq, colorectal cancer was the seventh top cancers, whereas in Kurdistan, it was the fourth most common cancer for both males and females. Although the methods of the diagnosis and therapy have been improved, only about 50% of the patients who resected the tumor died from disease within 5 years, due to distant metastasis. The study was carried out to determine the frequency of histopathological types of colorectal cancer, and to evaluate the correlation between colorectal cancer regarding the grade, stage, with different histological finding which include desmoplastic reaction, lymphocytic infiltration, foamy macrophages, necrosis, intraglandular necrosis, and calcification. Subject and Methods: This study includes (108) patients diagnosed with colorectal cancer. Cases were collected during the period January 2015-December 2017 from the histopathological department at Central Public Health Laboratory and other private labs in Duhok city. Clinical information were obtained from the available histopathological reports. Paraffin embedded blocks were sectioned and stained with immunohistochemistry markers; Ki67 and VEGF then processed automatically according to protocols supplied by the antibody manufacturer. Results: Patients age ranged from18-83 years with a mean of 54.42 years. The peak ages of the patients were between 60-69 years. Male: female ratio was 1.5:1. The commonest tumor location was (recto-sigmoidal region); rectum was (42.6 %) and sigmoid colon was(22.2%).Conventional adenocarcinoma was the predominant type 86(79.6%), majority of cases were moderately differentiated adenocarcinoma constituting85.2%. Stage III was the highest stage constituting 56(51.9%), followed by stage II which constitute 37(34.3%).The local invasion of the mucosa and other layers of colonic wall were associated with desmoplasia and collagen fiber remodeling. Infiltration of foamy macrophages decreased in number in relation to higher grade. Intraglandular necrosis showed significant correlation with tumor invasiveness, lymph node metastasis and grade. The frequency of both markers Ki67 and VEGF were 77 and 75 respectively. Ki67 immunoreactivity revealed significant relationship with tumor grade (P=0.014), whereas VEGF had significant relationship with TNM stage (P = 0.019), as well as the local invasion to the colorectal wall (P 0.009). Conclusions: Moderate differentiated adenocarcinoma (85.2%) and stage III (51.9%) were the most frequent diagnosed cases with colorectal cancer. Macrophages infiltration was conversely related with grading of colorectal cancer. Histopathological changes like desmoplastic reaction and intraglandular necrosis were common findings in colorectal cancer and they were in concordance correlation with stage and grade.Ki67 had relationship with tumor grade, whereas VEGF correlate with tumor invasion.