Exploration of the preponderant population for primary tumor resection of asymptomatic metastatic colorectal cancer / 国际肿瘤学杂志

ABSTRACT

Objective:To explore the population who benefit from primary tumor resection (PTR) of asymptomatic metastatic colorectal cancer (mCRC) .Methods:The clinicopathological data of 121 patients with asymptomatic mCRC with unresectable liver metastases treated in the First Affiliated Hospital of Yangtze University from January 2014 to January 2019 were retrospectively analyzed. Kaplan-Meier method was used to draw the survival curve accompanied with log-rank test. Cox regression model was used to analyze the prognostic factors.Results:The median overall survival (OS) of 121 mCRC patients was 20 months, and the 3- and 5-year survival rates were 34.71% and 10.74%. The median OS of PTR and non-PTR patients were 21 months and 18 months respectively, with no statistically significant difference ( χ2=0.79, P=0.375) . In 65 mCRC patients received targeted therapy, the median OS of PTR and non-PTR patients were 25 months and 28 months respectively, with no statistically significant difference ( χ2=1.65, P=0.199) . In 84 patients with mCRC of the left colon and rectum, the median OS of PTR and non-PTR patients were 24 months and 18 months respectively, with a statistically significant difference ( χ2=4.25, P=0.039) . In 37 patients with mCRC of the right colon, the median OS of PTR and non-PTR patients were 19 months and 17 months respectively, with no statistically significant difference ( χ2=0.18, P=0.675) . In 64 mCRC patients who received liver local treatment, the median OS of PTR and non-PTR patients were 36 months and 17 months respectively, with a statistically significant difference ( χ2=12.60, P<0.001) . In 57 mCRC patients who did not receive liver local treatment, the median OS of PTR and non-PTR patients were 15 months and 17 months respectively, with no significant difference ( χ2=0.58, P=0.445) . Univariate analysis showed that the location of the primary tumor ( HR=0.51, 95% CI 0.25-0.76, P=0.025) , the degree of differentiation ( HR=1.46, 95% CI 1.13-9.45, P=0.004) , the maximum diameter of the liver metastases ( HR=1.86, 95% CI 1.35-4.60, P=0.012) , the level of serum carcinoembryonic antigen ( HR=3.55, 95% CI 2.55-8.45, P<0.001) , local treatment of liver metastases ( HR=0.35, 95% CI 0.19-0.93, P<0.001) were influencing factors for OS of asymptomatic mCRC patients with unresectable liver metastases. Multivariate analysis showed that the primary sites of the left colon and rectum ( HR=0.43, 95% CI 0.25-0.93, P=0.039) , local treatment of liver metastases ( HR=0.78, 95% CI 0.27-0.86, P<0.001) were independent influencing factors for OS of asymptomatic mCRC patients with unresectable liver metastases. Conclusion:Asymptomatic mCRC patients with unresectable liver metastases with primary sites of the left colon and rectum and local treatment of liver metastases can benefit from PTR.