Prevalence of Liver Metastasis of Colorectal Cancer According to Clinical and Histopathologic Characteristics

ABSTRACT

PURPOSE: In Korea, the incidence of colorectal cancer is increasing quickly. The liver metastasis is the most common cause of death. But current diagnosis methods such as CT, MRI, USG have significant false negative rate (up to 15%) especially in micrometastasis. We designed this study to identify the predictive value of liver metastasis of known clinical and histopathologic factors. METHODS: Retrospectively, we reviewed 248 patients who underwent resection of colorectal cancer between 1997 and 1999. Clinical and histopathologic factors of colorectal cancer with synchronous liver metastasis was compared with those without liver metastasis. RESULTS: Twenty-nine patients had synchronous liver metastasis. In clinical factors, there was significant difference in liver metastatic rate according to tumors location, and serum carcinoembryonic antigen (CEA). The metastatic rate of right colon was 9.5%, left colon was 27.9%, rectum was 8.0% (P=0.001). The metastatic rate in cases with CEA or =5.0 ng/ml was 18.4% (P=0.001). In histopathologic factors, there was significant difference in liver metastatic rate according to depth of tumor invasion (T-stage), extent of lymph node metastasis (N-stage), venous invasion (9.5 vs 19.3 %, P=0.043), perineural invasion (8.5 vs 19.7 %, P=0.013). The metastatic rate of T1 was 0%, T2 was 3.43%, T3 was 12.3%, T4 was 26.9% (P=0.009). The metastatic rate of N0 was 4.9%, N1 was 15.6%, N2 was 30.3% (P=0.002). But there was no significant difference according to tumor size, histologic differentiation grade, lymphatic invasion. In multi- variant analysis with significant factors, independent factor associated with liver metastasis was N-stage. CONCLUSIONS: In colorectal cancer, tumor location, CEA, T-stage, N-stage, venous invasion, and perineural invasion of tumor cell had significant relationship with liver metastasis. The most important factor associated with liver metastasis was N-stage. This factors shoud be considered carefully in the planning treatment and follow up in colorectal cancer.