ABSTRACT
Colorectal carcinoma is the most common cancer of the gastrointestinal tract. More than 95.0% of the cancer is adenocarcinoma. Mucinous adenocarcinomas account for about 10.0% of all colorectal cancers. The expression of mucin themselves may play a role in the ability of tumors cells to escape the effect of systemic therapy and the process of tumor progression, invasion, survival and protection against the host immune response. The mucin lakes may also be a physiological barrier for the delivery of targeted therapy to the tumors cells. The aim of this study was to evaluate and compare the morphologic and histologic prognostic factors of mucinous and non-mucinous adenocarcinoma of the colon and rectum. In this descriptive cross-sectional type of observational study a total of 98 samples with colorectal adenocarcinoma were evaluated on the basis of presence or absence of the mucin from 2017 and 2018. The study was conducted in paraffin-embedded tumor tissue whose slides were stained using the hematoxylin-eosin technique. Mucin was evaluated by Periodic acid schiff and Diastase periodic acid schiff stain. Totally, 27 of 98 patients with colorectal adenocarcinoma (27.6%) had mucinous histologic subtype. Statistical significant results found in this research are as follows: Mucinous subtype tended to have present with moderate anaemia, history of low vegetable diet and larger tumor size, proximal colon involvement, infiltrative morphology and higher stage II compared to non-mucinous histologic subtype. Mucinous histologic subtype was associated with some adverse pathologic features in patients with colorectal cancer.