Prognostic role of CD10⁺ myeloid cells in association with tumor budding at the invasion front of colorectal cancer.

The expression of CD10 in tumor cells has been reported to correlate with liver metastasis in colorectal cancer (CRC). However, fibroblasts and immune cells positive for CD10 at the tumor invasion front have not been comprehensively studied. We classified CD10 expression patterns into three types of cells, tumor cells (tCD10), stromal myofibroblasts (sCD10), and immune cells (iCD10), and investigated their correlation with the expression of transforming growth factor-β (TGF-β1) protein and tumor budding grade. Several cell surface markers were stained to detect the phenotype of iCD10(+) cells, including CD3, CD20, CD11b, CD14, CD15, and CD163. Specimens and follow-up data of 206 CRC patients were examined. In multivariate analysis, iCD10 could be an independent prognostic factor for both recurrence-free survival and overall survival in stage I-III CRC (hazard ratio, 2.522 [1.299-4.896], P = 0.006; 2.890 [1.357-6.157], P = 0.006, respectively). The expression of sCD10 and iCD10 was strongly correlated with TGF-β1 expression in tumor cells and tumor budding grade. The phenotype of iCD10(+) cells was CD11b(+) and CD15(+) granulocytes. The infiltration of sCD10(+) fibroblasts and iCD10(+) granulocytes at the tumor invasion front might interact with TGF-β1 protein expression and enhance tumor budding grade. The expression level of iCD10 at the tumor invasion front represented an independent prognostic biomarker in stage I-III CRC and could be integrated into a new staging system.