en Infectious Diseases Infectious Diseases Original Article Original Article <p align="left" style="direction: ltr;"><font face="Times New Roman" size="3">&nbsp;</font><font face="times new roman,times,serif"><b><i><span><font face="times new roman,times,serif">Background:</font> </span></i></b><span style="font-size: 10pt;"><font face="times new roman,times,serif">Gastric and colorectal adenocarcinoma are the second and the fifth most common cancers in Iran, respectively. Expression of cytokeratin 7 (CK7) is established in most malignancies including gastric and colorectal adenocarcinoma. Demonstration of Ck7 could be related to prognostic factors and help to the better management of the patients. The objective of our study was to evaluate the CK7 expression in gastric and colorectal adenocarcinoma and its correlation with other prognostic factors.</font></span></font></p> <p align="left" style="direction: ltr;"><font face="times new roman,times,serif"><font size="3">&nbsp;</font><b><i><span><font face="times new roman,times,serif">Methods:</font></span></i></b><span style="font-size: 10pt;"> <font face="times new roman,times,serif">This cross-sectional study was performed on 99 tissue blocks from patients with gastric or colorectal adenocarcinoma undergoing surgery. Tumor grade,<span style="mso-spacerun: yes;"><font size="2">&nbsp;</font></span>tumor size, depth of invasion and metastasis to lymph nodes were determined. Then, the expression of CK7 was studied using immunohistochemistry staining.</font></span></font></p> <p align="left" style="direction: ltr;"><font face="times new roman,times,serif"><font size="3">&nbsp;</font><b><i><span><font face="times new roman,times,serif">Results:</font></span></i></b><span style="font-size: 10pt;"> <font face="times new roman,times,serif">Expression of CK7 was 50% and 33.8% in gastric and colorectal adenocarcinoma, respectively. There was not only a significant correlation between CK7 expression and tumor size (r=0.267, P=0.009) but also histologic grade (r=0.222, P=0.028).</font></span></font></p> <p align="left" style="direction: ltr;"><font face="times new roman,times,serif"><font size="3">&nbsp;</font><b><i><span><font face="times new roman,times,serif">Conclusion:</font> </span></i></b></font><span style="font-size: 10pt;"><font face="times new roman,times,serif">CK7 could be more expressed with the increase in tumor size and was associated with poorly differentiated gastric and colorectal adenocarcinoma. However, with these results gathered, it is highly recommended that further studies will be conducted to reveal the exact prognostic role of this factor.</font></span></p> <p align="left" style="direction: ltr;"><font face="Times New Roman" size="3">&nbsp;</font></p> Cytokeratin 7, Colorectal Cancers, Gastric Cancers, Prognosis 229 232 http://caspjim.com/browse.php?a_code=A-10-66-1&slc_lang=en&sid=1 Mohammadreza Jalalinadoushan jalalinadooshan@yahoo.com 10031947532846005687 10031947532846005687 No Shahed University, Tehran, Iran Sepideh Siadati siadati_sepideh@yahoo.com 10031947532846005688 10031947532846005688 Yes Babol University of Medical Sciences, Babol, Iran Ali Davati davati@yahoo.com 10031947532846005689 10031947532846005689 No Shahed University, Tehran, Iran Gholamreza Torabi-Parizi Torabi@yahoo.com 10031947532846005690 10031947532846005690 No Shahed University, Tehran, Iran Samira Ghasemi Ghasemi@yahoo.com 10031947532846005691 10031947532846005691 No Shahed University, Tehran, Iran