Prognostic Factors And Survival Analysis Of Pulmonary Metastases And Hepatic Metastases In Colorectal Cancer

Objective:To analyse survival of patients with pulmonary metastases in colorectal cancer (CRPM) and prognostic factors influencing survival, and to compare survival of patients with CRPM with that of patients with hepatic metastases in colorectal cancer (CRHM).Methods:This study was a retrospective study. From July1994to December2010, data on90patients with CRPM and195patients with CRHM were reviewed. Of90patients with CRPM,34cases underwent pulmonary R0metastasectomy and another56patients were treated with chemotherapy. Among90patients with CRHM,50patients underwent hepatic R0metastasectomy and another56patients were treated with chemotherapy. Survival was analyzed by the Kaplan-Meier method. The log-rank test was used for univariate analysis, the Cox proportional hazards model for multivariate analysis, and the χ2test for balance examination on the clinical data of every two groups.Results:For90patients with CRPM,1-,2-and3-year overall survival (OS) rate was87.8%,67.8%and49.1%. For the R0pulmonary resection group and systematic chemotherapy group,1-,2-and3-year cumulative survival rate was97.1%vs.82.1%,88.2%vs.55.3%and74.9%vs.32.4%(P<0.05), respectively; for the R0pulmonary resection group,1-,2-and3-year disease-free survival (DFS) rate was64.7%,44.1%and34.1%, respectively. On univariate analysis, disease-free interval (DFI)(<12months vs.≥12months)(P=0.042), hilar or mediastinal lymph node metastasis in colorectal cancer (P=0.002), the maximum tumor size of pulmonary metastases (<4cm vs.≥4cm)(P=0.009) and a preoperative serum carcinoembryonic antigen (CEA) level (P=0.026) were significantly correlated with overall survival of the R0pulmonary resection group. And lymph node metastasis after curative resection of the primary tumor (P=0.005), a preoperative serum carcinoembryonic antigen (CEA) level (P=0.011) and the maximum tumor size of pulmonary metastases (P=0.006) were related to relapse after the R0pulmonary resection. For the systematic chemotherapy group, age (<65years vs.>65years)(P=0.005) and the percentage of patients who received all three drugs (FU/LV, irinotecan and oxaliplatin) in the course of their disease was significantly correlated with overall survival. On multivariate analysis, DFI≥12months (P=0.012) and the maximum tumor size of pulmonary metastases<4cm (P=0.025) were the favorable independent prognostic factors for the overall survival of the RO pulmonary resection group, the positive lymph node metastasis after curative resection of the primary tumor(P=0.027)and the maximum tumor size of pulmonary metastases≥4cm (P=0.049) were the adverse independent prognostic factors for recurrence after the RO pulmonary resection. The use of all three drugs in the course of their disease was the favorable independent prognostic factor for the overall survival of the systematic chemotherapy group.For195patients with CRHM,1-,2-and3-year cumulative survival rate was77.9%,37.4%and21.5%. For the RO hepatic resection group and chemotherapy-based group,1-,2-and3-year cumulative survival rate was94.0%vs.72.4%,74.0%vs.24.8%and59.9%vs.8.7%(P<0.001), respectively; for the hepatic RO resection group,1-,2-and3-year disease-free survival rate was58.0%,29.2%and17.5%, respectively. For systematic chemotherapy group and systematic chemotherapy combined with local treatment group,1-,2-and3-year cumulative survival rate was63.6%vs.86.0%,8.2%vs.35.1%. and2.4%vs.18.9%(P<0.001). On univariate analysis, the number of hepatic metastases (<3)was the favorable independent prognostic factor for OS and DFS of the RO hepatic resection group, P=0.037and0.044. For systematic chemotherapy group, the percentage of patients who received all three drugs (FU/LV, irinotecan and oxaliplatin) in the course of their disease (P=0.008) and the number of hepatic metastases (1vs.≥2)(P=0.039) were related to OS. No factor was found to influence on OS of systematic chemotherapy combined with local treatment group. On multivariate analysis, the use of all three drugs in the course of their disease (P=0.002) and only one hepatic metastasis (P=0.034) was the positive independent prognostic factor for OS of systematic chemotherapy group.For the R0pulmonary resection group and R0hepatic resection group,3-year overall survival rate was75.5%vs.59.9%(P>0.05), and3-year disease-free survival rate was34.1%vs.19.6%(P>0.05). For patients with CRPM and those with CRHM who received systematic chemotherapy,3-year overall survival rate was32.4%vs.2.4%(P<0.05). For systematic chemotherapy group with CRPM and systematic chemotherapy combined with local treatment group with CRHM,3-year overall survival rate was32.4%vs.18.9%(P>0.05)Conclusion:The RO pulmonary resection of pulmonary metastases in colorectal cancer significantly improved overall survival, especially in patients with the maximum tumor size(<4cm) of pulmonary metastases and DFI≥12months. For patients with RO resection of metastases, there was no significant difference between the CRPM group and the CRHM group. For patients treated with systematic chemotherapy, overall survival of the CRPM group was longer than that of the CRHM group.