The Risk Factors Of Lymph Node Metastasis And Prognosis In T1 Colorectal Cancer

Objective To investigate the effects of different invasion depths and risk factors of lymph node metastasis and prognosis in T1 colorectal cancer,And provide reference for the clinical treatment decision of T1 patients with colorectal cancerMethods A total of 253 patients with T1 colorectal cancer were enrolled in the Retrospective analysis in the Department of Colorectal Surgery,Union Hospital,Fujian Medical University from January 2000 to December 2016.The patients were divided into two groups according to whether the lymph node metastasis occurred,analyze the difference of lymph node metastasis rate between the three groups with the depth of invasion(sm1,sm2,sm3),And then the clinical and pathological data of the two groups were analyzed by ?2 test for univariate analysis,seeking out the significant factors,and then Logistic multivariate regression analysis to find the independent risk factors for lymph node metastasis.The different depths of invasion(sm1,sm2,sm3)three group and lymph node metastasis positive(LNM+)and lymph node metastasis negative(LNM-)two groups respectively of 5 years disease-free survival rate(5-DFS)and the 5 year overall survival rate(5-OS)were tested by Kaplan-Meier test system.The differences between groups were tested by Log-rank method.To investigate the prognostic value of lymph node metastasis in patients with T1 colorectal cancer.Cox univariate regression analysis and multivariate regression analysis were used to explore the prognostic risk factors in patients with T1 colorectal cancer.Result 1.Of the 253 patients with T1 colorectal cancer,25 had lymph node metastasis Positive(LNM +),228 had lymph node metastasis negative(LNM-),and the lymph node metastasis rate was 9.9%;2.sm1 49 cases,sm2 68 cases,sm3 136 cases,The lymph node metastasis rate sm1,sm2,sm3 were 0 cases(0%),6 cases(8.8%),19 cases(14%),The overall three groups of lymph node metastasis rate had statistical significant difference.subgroup analysis showed that in the sm1/sm3 subgroup the rate of lymph node metastasis is statistical significant,there was no statistical difference between the sm2/sm3 and sm1/sm2 subgroups.3.The patients were divided into two groups according to whether the lymph node metastasis occurred,And The clinical and pathological data of the two groups were analyzed by ?2 test.It was suggested that the histological differentiation,histological type,lymphovascular thrombosis and Submucosal invasion depth were Statistical significant differences in the two groups,and the logistic multivariate regression analysis showed that the independent risk factors are: histological poorly differentiation,mucinous adenocarcinoma(OR=9.555,95%CI 3.429-26.624,P=0.000)and Submucosal invasion depth(OR=2.742,95%CI 1.153-6.521,P=0.023)? 4.The 5-year disease-free survival rate(5-DFS)was(75.9% vs 94.4%,P = 0.001)for lymph node metastasis Positive(LNM +)and lymph node metastasis negative(LNM-)and The 5-year overall survival rate(5-OS)was(76.5% vs 95.0%,P = 0.003).Cox univariate regression analysis and Cox multivariate regression analysis were used to analyze the risk factors of 5-year disease-free survival rate,suggesting that the prognostic risk factors were lymph node metastasis,poorly histological type and exist lymphovascular thrombosis.Further more histological type low differentiation,mucinous adenocarcinoma(OR=18.205,95%CI 5.282-62.745,P=0.000)and exist lymphovascular thrombosis.(OR=6.069,95%CI 1.380-26.697,P=0.017)are as independent risk factors.Conclusion 1.The depth of submucosal invasion of sm2 or above and with histological low differentiated,mucinous adenocarcinoma and tumor thrombus are as high risk factors of lymph node metastasis and prognosis in T1 colorectal cancer;2.For those with high risk factors of T1 stage colorectal cancer patients underwent local resection additional thrapies are needed.