Survival Analysis and Prognostic Predictor Study of Colorectal Cancer Patients with Single-Site Metastasis

Metastatic colorectal cancer (mCRC) patients have various metastasis patterns, which reflect diverse biological characteristics of different patient subgroups. We analyse the prognosis of mCRC patients according to the metastatic site and clarify the relationship between tumor or patient characteristics and the metastatic sites. The whole sequencing and clinical data of 2329 CRC patients were obtained from TCGA and a database of the MSKCC. Kruskal Wallis Tests were used to analyse measurement data. Survival was illustrated by Kaplan-Meier curves, with P value determined by Log-rank Test. Hazard’s ratio was determined through the univariate and multivariate COX proportional hazards regression model. The mortality rate of CRC patients with liver-only metastasis (mCRC-liver) did not increase versus nonmetastatic patients. The survival rate of patients with non-regional lymph node-only metastasis (mCRCNRLN) was lower versus mCRC-liver. Mutations of KRAS and TCF7L2 genes were associated with mortality of mCRC-liver. APC mutation was associated with reduced mortality in mCRC-lung and mCRCNRLN. BRAF mutation was associated with increased mortality of mCRC-peritoneum. In a multivariate COX analysis, gender affected the survival rate of mCRC-liver. Age and the number of gene mutations affected the survival rate of mCRC-lung and mCRC-NRLN respectively. Receiving chemotherapy is an unfavourable factor for prognosis of mCRC-liver, but the length of chemotherapy treatment is an advantageous prognosis factor. This study depicts the long-term survival features of a group of mCRC patients. These findings promoted our understanding of the prognosis characteristics of CRC and have positive guiding significance for clinical management of CRC patients.