[Expression of CD44 isoforms--a new histopathologic parameter in colorectal carcinoma?].

Expression of CD44H and CD44-isoforms were examined by immunohistochemistry in 102 patients with colorectal tumors in correlation to histological grading, staging and clinical outcome. From normal mucosa to colorectal tumors we found an upregulation of CD44H and CD44-v9 and a de-novo expression of CD44-v6. When compared to histological grading it was found that CD44-v6 expression indicates more differentiated tumors in contrast to less differentiated colorectal carcinomas showing decreasing CD44-v6 expression. Further we came to the result that increasing CD44-v6 expression correlates with progressive tumor stage. In the metastases we found a significant decrease in expression of CD44H, CD44-v9 and-v6 when compared to corresponding primary colorectal tumors. Wether the differential CD44 expression can be used as a prognostic histopathological marker for the progression of colorectal cancer has to be further validated. For final interpretation, our prospective study has to be continued further.