Survival Analysis Of 109 Patients With Metastatic Colorectal Cancer Treated By Third-line Therapy

[Objective]Colorectal cancer is one of the most common tumors in the world, metastatic colorectal cancer has a poor prognosis and the 5-year survival rate is only 8.1%. There's no standard therapy to oxaliplatin-and irrinotecan-resistant colorectal cancer. This study is designed retrospectively to illustrate compare the effect of different third line regimens and the correlation between clinical features and survival.[Methods]We enrolled third-line therapy treated colorectal cancer patients in the First Affiliated Hospital of Suchou University between Sep 2006 and Dec 2009. Via Statistical software SPSS 16.0, we analyzed the relevance of prognostic factors and survival. Overall survival and progression free survival of different third line regimens were compared retrospectively. Log-Rank test is used to single factor analysis and compare the survival curves, COX regression model used to multiple factor analysis. Kaplan-Meier methods were used to describe survival and time to progression using the log-rank test at the two-sided 0.05 level.[Results]1.109 patients were enrolled. The median overall survival was 9.0 month (3.1-18 month). The median follow-up duration was 37month(15-55 month). The one year survival rate was 23.7%.2. The median PFS of chemotherapy combined with targeted therapy(5.0 month) was superior to chemotherapy alone (3.0month) (P<0.05); the median PFS of combined themotherapy(3.1 month) was superior to single agent chemotherapy (2.0 month)(P<0.05). The median PFS of the FOLFIRI, FOLFOX/XELOX and FOLFOXIRI regimen was 3.9month,4.0month and 2.3month respectively. P=0.0241. The FOLFIRI regimen was superior to FOLFOXIRI regimen(P<0.05). The FOLFOX regimen was superior to FOLFOXIRI regimen(P<0.05). There were no significant difference between the FOLFOX/XELOX and FOLFIRI regimens(P=0.5483).3. The median OS of the chemotherapy combined with targeted therapy(13.1 month) was superior to chemotherapy alone(7.2month) (P<0.05), and the median OS of combined themotherapy(7.8 month) was superior to single agent chemotherapy (5.0month) (P<0.05). The median OS of the FOLFIRI, FOLFOX/XELOX and FOLFOXIRI regimen was 7.8month,11.9month and 7.2month respectively. There were no significant difference between the three regimens(P=0.0732).4. Single factor analysis showed:patients with the lower CEA level and better PS status at the baseline of third-line therapy, less metastasis, all three toxic drugs (5-FU, irinotecan and oxaliplatin) involved during the first and second line therapy had a longer OS(P<0.05, P<0.05, P<0.05, P<0.05). Sex, age, primary tumor site, liver or lung metastasis, anemia and PFS of second line therapy have no significant impacts on prognosis.5. Multiple factor analysis showed the CEA level and PS status in the initial of the third line therapy were the main independent predictors on the overall survival of third line therapy(P<0.05, P<0.05).6. There were 67 patients using adjuvant therapy in the initial. We found patients with longer DFS of the adjuvant therapy got a longer OS(P<0.05).[Conclusion]1. Different third line regimens of colorectal cancer have different effect, we should select according to circumstances.2. The CEA level and PS status at the baseline of third-line therapy, number of metastasis, three toxic drugsoxic drugs (5-FU, irinotecan and oxaliplatin) used during first and second line therapy and DFS of the adjuvant therapy have impacts on the third line survival. The CEA level and PS status in the initial of the third line therapy were the main prognostic factors.