Novel methods for clinical risk stratification in patients with colorectal liver metastases

Abstract

Purpose: Colorectal cancer patients with liver-confined metastases are classified as stage IV, but their prognoses can differ from metastases at other sites. In this study, we suggest a novel method for risk stratification using clinically effective factors.

Materials and methods: Data on 566 consecutive patients with colorectal liver metastasis (CLM) between 1989 and 2010 were analyzed. This analysis was based on principal component analysis (PCA).

Results: The survival rate was affected by carcinoembryonic antigen (CEA) level (p < 0.001; risk ratio, 1.90), distribution of liver metastasis (p=0.014; risk ratio, 1.46), and disease-free interval (DFI; p < 0.001; risk ratio, 1.98). When patients were divided into three groups according to PCA score using significantly affected factors, they showed significantly different survival patterns (p < 0.001).

Conclusion: The PCA scoring system based on CEA level, distribution of liver metastasis, and DFI may be useful for preoperatively determining prognoses in order to assist in clinical decisionmaking and designing future clinical trials for CLM treatment.

Keywords: Colorectal neoplasms; Liver metastasis; Patient stratification; Risk calculation.

Fig. 1.

Comparison of accuracy, specificity, and sensitivity in training and test data sets. Results are from 500 rounds of simulation. The sizes of training and test data sets were 396 (70%) and 170 (30%), respectively. The symbol×indicates accuracy, specificity, and sensitivity of Fong’s criteria.

Fig. 2.

Kaplan-Meier survival curves of risk groups defined by principal component analysis scores. Comparison of three risk groups (A); group 1 vs. group 2 (B); and group 2 vs. group 3 (C).

Fig. 3.

Kaplan-Meier survival curves of risk groups defined by Fong’s score. (A) Comparison of survival patterns between two vs. six groups. (B) Pairwise comparisons.