Association of CAF-Related Stromal Markers and IMP3 Expression With Lymph Node Metastasis in Early Colorectal Cancer

Accurate risk stratification for lymph node metastasis (LNM) is needed after endoscopic resection of early-stage colorectal cancer (CRC). We explored the associations of cancer-associated fibroblast (CAF)-related markers and insulin-like growth factor 2 mRNA-binding protein 3 (IMP3) expression with LNM. We analyzed data from 155 patients with pT1 CRC who were treated by primary or additional surgery after endoscopic resection. A matched case-control cohort comprising 18 patients with LNM and 29 LNM-negative controls was immunohistochemically analyzed. The area fraction and staining intensity of podoplanin (D2-40), hydrogen peroxide-inducible clone-5 (Hic-5), α-smooth muscle actin (αSMA), and IMP3 were assessed using image analysis. We evaluated CAF-related stromal markers in the superficial, middle, and invasive front regions and IMP3 in tumor areas. Decreased D2-40 expression at the invasive front showed a nominal association with LNM. Associations between LNM and each of Hic-5, αSMA, and IMP3 were not statistically significant. These hypothesis-generating findings suggest an association between reduced invasive-front D2-40 expression and LNM in pT1 CRC.