Abstract: Objective:To investigate the clinical efficacy for different treatments of stage Ⅳ right colorectal cancer and its prognostic factors.
Methods:The clinical data of 106 patients with stage Ⅳ right colorectal cancer who were admitted to the First People′s Hospital of Chenzhou from January 2008 to December 2013 were retrospectively analyzed. Among the 106 patients, 42 patients receiving palliative resection were allocated to the palliative resection group, 30 patients receiving colostomy were allocated to the colostomy group, 20 patients receiving bypass surgery were allocated to the bypass group and 14 patients without treatment were allocated to the nontreatment group. Fluorouracil+leucovorin (5FU/LV) were used as postoperative chemotherapeutics, and the time of chemotherapy was 2 to 6 months. The followup was applied to the patients by outpatient examination and telephone interview till February 2014. The nonnormal distribution data were described as median and range.  The survival curve was drawn by KaplanMeier method, and the survival rate was analyzed using the Logrank test. The continuous variables were cut into the categorical variables. The univariate analysis of categorical  variables was done using chisquare test, and the multivariate analysis was done using the COX regression model.
Results:The incidences of postoperative complications in the palliative resection group,in the colostomy group and  in the bypass group were 47.6%(20/42), 40.0%(12/30) and 65.0%(13/20), respectively, with no significant difference (χ²=3.053, P>0.05). Onehundred patients were followed up for 14.0 months (range, 3.0-40.0 months), with overall median survival time of 10.3 months (range, 2.6-27.0 months) and the 1, 2year survival rates of 36.8% and 6.7%. The median survival time and 1, 2year survival rates were 11.5 months (range, 4.3-27.0 months ), 47.6%, 16.7% in the palliative resection group, 8.5 months (range, 3.5-18.0 months ), 20.0%, 0 in the colostomy group, 9.0 months (range, 3.0-13.0 months), 15.0%, 0 in the bypass surgery and 5.0 months (range, 2.6-10.0 months ), 0, 0 in the nontreatment group, showing a significant difference in the prognosis of patients among the 4 groups (χ²=42.395, P<0.05). The prognosis of patients in the palliative resection group were significantly different from those in the other 3 groups (χ²=5.786, 6.178, 10.378, P<0.05), there was no significant difference in the prognosis of patients between the colostomy group and the bypass surgery group (χ²=0.203, P>0.05). The results of univariate analysis showed that T stage, N stage, tumor differentiation, preoperative obstruction, peritoneal implantation, methods of treatment, chemotherapy and postoperative complications were related factors affecting the prognosis of patients with stage Ⅳ right colorectal cancer (χ²=37.428, 48.586, 32.550, 22.739, 33.562, 42.395, 21.517, 11.530, P<0.05). T4 stage, N2 stage, poordifferentiated tumors and peritoneal implantation were independent risk factors affecting the poor prognosis of patients with stage Ⅳ right colorectal cancer (RR=2.336, 2.945, 2.182, 3.500, 95% confidence interval: 1.10²-4.953, 1.156-7.501, 1.003-4.749, 1.573-7.787, P<0.05). The postoperative chemotherapy was an independent factor affecting the good prognosis of patients with stage Ⅳ right colorectal cancer (RR=0.495, 95% confidence interval: 0.271-0.904, P<0.05).
Conclusion:Palliative resection can improve the prognosis of patients with stage Ⅳ right colorectal cancer. T4 stage, N2 stage, poordifferentiated tumor, and peritoneal implantation were independent risk factors affecting the poor prognosis of patients with stage Ⅳ right colorectal cancer, while postoperative chemotherapy was an independent factor affecting the good prognosis of patients with stage Ⅳ right colorectal cancer.