Factors that influence survival in unresectable metastatic or locally advanced colorectal cancer

Half of patients with colorectal cancer (CRC) have metastasis during the whole course of the disease. Fewer than 10% of those are still alive at 5 years. Locally advanced CRC accounts for 7% to 33% of CRC relapses. Of these, only a small number of patients are resectable with a curative intent. Management of unresectable metastatic or locally advanced CRC is a significant challenge. In this study, we focus on patients with unresectable locally advanced or metastatic CRC and analyze survival rate and prognostic factors influencing the survival.

There were 277 patients identified. Several clinicopathologic parameters were evaluated. To determine the prognostic impact of the factors in survival, all parameters were tested from their relationship in Cox-regression model and Cox proportional hazards model. Survival curves were generated according to Kaplan-Meier method and the differences in survival were determined by employing the log-rank test.

Three factors that influence the survival were identified: one or more than two organs involved (p = 0.041), higher carcinoembryonic antigen (CEA) level (p = 0.001), and different salvage treatment (p < 0.001). In Kaplan-Meier survival analysis, there were significant differences between patients with one and more than two organs involved (p = 0.027), different ranges of CEA level (p = 0.004), and different salvage treatment (p < 0.001).

We clearly demonstrated three factors that influence the survival, including more than two organs involved, higher CEA level, and different salvage treatment. The higher the CEA level and the more organs (≥2) involved, the worse the survival. Even in patients with unresectable metastatic or locally advanced, aggressive treatment with target therapy seems to have survival benefit.