Chromosome 18q Deletion as a Novel Molecular Predictor for Colorectal Cancer With Simultaneous Hepatic Metastasis

Abstract

Currently, surgical treatment for colorectal hepatic metastasis is performed with low mortality and morbidity rates. However, there is no definitive marker that predicts patient outcome. The aim of this study is to identify the molecular predictor of survival along with its clinical properties. Fifty-six patients were surgically treated for colorectal cancer and synchronous hepatic metastasis from January 1994 to December 2004. Clinicopathologic and molecular factors were reviewed in association with overall survival (OS) and disease-free survival (DFS). Chromosome 18q deletion in the primary tumor was a molecular predictor that affected OS (P=0.021). Decreased expression of the Smad4 protein tended to affect the outcome; however, no statistical significance was observed (P=0.29:OS, P=0.45:DFS). Preoperative carcinoembryonic antigen (P=0.013) and carbohydrate antigen 19-9 (CA19-9) (P<0.0001) levels were poor clinical predictors of OS. The number of primary lymph nodes was the only pathologic factor that affected DFS (P=0.0052). The number and diameter of hepatic metastasis had no influence on survival. In conclusion, we demonstrated that chromosome 18q deletion, in conjunction with high carcinoembryonic antigen and CA19-9 levels, is an unfavorable prognostic factor. This novel molecular predictor is helpful in identifying patients who would benefit from surgical resection.