Influence of malignant left large bowel obstruction in metastatic left-sided colon cancer patients during chemotherapy on survival: A Propensity Score Analysis

Abstract

AbstractBackgroundChemotherapy was recommended to improve the long-term outcomes of metastatic colorectal cancer (mCRC). The process of chemotherapy may be interrupted by malignant large bowel obstruction (MLBO). The aim of this study was to find out the Oncologic outcomes for MLLBO in metastatic left-sided colon cancer (mLCC) patients during chemotherapy.MethodsConsecutive mLCC patients who underwent chemotherapy from June 2009 to July 2021 in West China Hospital were divided into two groups according to whether MLLBO occurred during chemotherapy. Patients were propensity matched 1:2 into MLLBO and no-MLLBO groups and among the matched cohort, the univariable and multivariable Cox proportional hazards regression models were performed to identify predictors of survival. Potential variables were evaluated first with univariate and then multivariate analyses to identify the risk factors of tumor characteristics for MLLBO patients.ResultsOf 1638 mLCC patients diagnosed, 156 were identified in the matched cohort. The median overall survival was 34.0 months, 51.0 months in the non-MLLBO, and MLLBO groups, respectively (p= 0.020) and the corresponding median progression-free survival was 12.0 months, 23.0 months, respectively (p=0.018). Multivariable Cox regression analysis demonstrated that MLLBO was independently associated with reduced overall survival (hazard ratio [HR]= 1.473, 95% CI 1.186-1.812, P＜0.001) as well as progression-free survival (hazard ratio [HR]= 1.619, 95% CI 1.391-1.899, P＜0.001). In addition, Tumor length ≥ 10 cm (P=0.043) and TTI ≥ 1.5 cm (P＜0.001) were identified as independent risk factors of tumor characteristics for MLLBO patients.ConclusionNo-MLLBO patients had better prognosis than MLLBO patients during chemotherapy. Prevention measures are recommended for mLCC patients with higher risk factors of MLLBO during chemotherapy.