| Background and purposeColorectal cancer is a common malignant tumor of the digestive tract.The liver is the most common metastatic target organ of colorectal cancer.It is estimated that up to 25% of patients with colorectal cancer have synchronous liver metastases,about 60% patients were found to have recessive liver metastases at follow-up.The median survival time of patients with colorectal liver metastasis without any treatment was 8-10 months,and the 5-year survival rate was less than 5%.Surgical resection is currently the gold treatment of choice for colorectal liver metastasis,but about 80-85% of these patients are inoperable at the time of diagnosis due to combined extrahepatic disease and insufficient residual liver reserve after surgical resection.In recent years,local ablation of liver tumors has gradually matured and has been proved to be an effective means for the treatment of malignant liver injury.Among them,microwave ablation is a new treatment option that has been recognized for more than ten years.This study was to investigate the efficacy and safety of percutaneous microwave ablation for patients with liver metastases after colorectal cancer surgery,and to provide a clinical basis for microwave ablation of colorectal cancer liver metastases.Materials and methodsRetrospective analysis of 35 patients with colorectal cancer liver metastases who underwent CT-guided percutaneous microwave ablation between January 1,2014 and December 31,2017,including 27 males and 8 females.Ablation was performed using a Nanjing Yigao Cold Cycle ECO-100 E microwave therapy device,and an enhanced CT cross-sectional image was used to assess the diameter of the ablation zone,complete ablation,and local recurrence.All data were processed by SPSS19 statistical analysis software,and the count data were expressed by frequency and percentage,such as gender,primary tumor type,and time of liver metastasis;metrological data were expressed by mean ± standard deviation,such as age,tumor Maximum diameter of the cross section,number of tumors,progression-free survival after ablation,and overall survival.The Kaplan-Meier method was used to calculate the overall survival and progression-free survival.Log-rank test was used to compare the differences of survival curves.COX multi-factor regression was used to analyze various influencing factors by Log rank single factor analysis.P < 0.05 was considered statistically significant.ResultsThe median overall survival was 37 months(range 4-40),and the median postoperative progression-free survival was 7 months(range 2-15).The 1-,2-,and 3-year overall survival rates of patients were 94.3%,80.0%,and 51.4%,respectively.The half-year and1-year disease progression-free survival rates were 51.4% and 31.4%,respectively.KaplanMeier univariate analysis showed that the number of liver metastases,tumor diameter and time of tumor metastasis were statistically significant(P<0.05)in disease-free survival and overall survival after ablation.The multivariate analysis of single-factor analysis by log rank using COX multivariate regression showed that the time of liver metastasis and the number of tumors were independent risk factors for disease-free survival and overall survival after metastasis in patients with metastasis.Academic significance(both P<0.05).The adverse reactions in all cases in this study were local pain and fever.There were3 cases(8.6%)with mild pain during treatment and after treatment,and 1 case(2.9%)with mild vomiting.ConclusionMicrowave ablation for liver metastasis of colorectal cancer is safe and has slight complications.Microwave ablation for isolated liver metastasis had the best result.The time of liver metastasis is independent factors affecting survival rate. |
