Background: Prediction of poor patient outcome as a effect of adjuvant therapy in stage II colorectal cancer (CRC) remains a matter of controversy. Tumor expression of CD10 and CD15 is reportedly related to poor outcome in CRC. In this study, we investigated whether the expression of CD10 and CD15 is a predictor of outcome and the effect of adjuvant therapy in stage II CRC.
Materials and methods: Immunohistochemical analyses for CD10 and CD15 and some additional markers (CD11b, CD14, CD163, CD3, and CD20) were performed using paraffin sections of CRC specimens from 57 patients who had undergone curative surgical treatments between 1998 and 2004. Forty of these patients received postoperative adjuvant therapy. We distinguished between expression in tumor cells (tCD10 and tCD15), in stromal cells (sCD10), and infiltrating immune cells (iCD10 and iCD15).
Results: Expression of iCD10 was observed in 21.1% (12/57) of the specimens examined. Of all expression patterns, only iCD10 expression at the cancer invasion front was a useful predictor of a disease-free period and overall survival in stage II CRC. Adjuvant therapy improved the outcome of iCD10(+) patients. CD10(+) immune cells were heterogeneous in origin and partially overlapped the cells positive for myeloid lineage markers, including CD11b and CD15.
Conclusions: iCD10 expression at the tumor invasion front is a useful marker for predicting a high risk of recurrence and mortality in stage II CRCs. CD10(+) immune cells appear to be of myeloid origin.