Low CADM2 expression predicts high recurrence risk of hepatocellular carcinoma patients after hepatectomy.

ABSTRACT

PURPOSE: To investigate the expression and clinical significance of CADM2 in hepatocellular carcinomas (HCC). METHODS: The level of expression of CADM2 mRNA was assessed in frozen tumor specimens and adjacent noncancerous tissues from 30 HCC patients by real-time PCR. The protein level was determined by immunohistochemistry on a tissue microarray containing tumor and adjacent noncancerous tissues from 234 HCC patients. Clinicopathological characteristics associated analysis was performed through SPSS18 . RESULTS: CADM2 was strikingly down regulated in HCC. CADM2 expression was associated with differentiation (P = 0.000), serum alpha-fetoprotein (P = 0.003), vascular invasion (P = 0.001), and hepatitis B surface antigen (HBsAg, P = 0.038). Furthermore, patients with low CADM2 expression had significantly poorer recurrence-free survival (RFS) (40.8 and 34.2 % vs. 56.3 and 50.1 % in 3- and 5-year RFS, respectively, P = 0.005). Subgroup analysis revealed that the difference in RFS between groups with low- and high-CADM2 expression still existed among patients belonging to stage 0 or A of BCLC staging system (P = 0.008), patients with tumor ≤5 cm in size (P = 0.013), and alpha-fetoprotein-negative patients (P = 0.003). Moreover, low expression was more frequently observed in the early recurrence group (within 2 years, P = 0.007). Further multivariate Cox regression analysis indicated that CADM2 expression level, tumor size, tumor number, vascular invasion, HBsAg were independent risk factors for HCC recurrence. CONCLUSION: CADM2 serves as a novel predictor of RFS in HCC patients after curative resection.