Predictive Factors Of Lymph Node Metastasis In Clinical T1N0 Non-small Cell Lung Cancer Based On PET-CT

Objective: Lung cancer is the main cause of cancer-related mortality in the world.More than 80% of lung cancer is non-small cell lung cancer.The 5-year survival rate of clinical stage I non-small cell lung cancer is between 40% and 90%.The incidence of postoperative recurrence or metastasis is about 20%,and one of the important reasons for this phenomenon is occult lymph node metastasis.Therefore,this paper analyzes the prognostic effects of the maximum diameter of tumor,the PET-CT parameter SUVmax value and the proportion of micropapillary components>5% on the occult lymph node metastasis in patients with clinical stage T1N0 NSCLC.Methods: The clinical data of 116 patients with stage I non-small cell lung cancer who underwent thoracoscopic lobectomy in the Department of Thoracic Surgery,First Affiliated Hospital of China University of Science and Technology from January 2010 to December 2019 were analyzed retrospectively.According to the postoperative pathology,the patients were divided into 91 cases in group A(p N0)and 25 cases in group B(p N1 or N2).The clinicopathological characteristics,median survival time and overall survival rate of 1 and 3 years after operation were compared and analyzed.Results: There was no significant difference in age,sex,smoking history,preoperative complications,number and number of lymph nodes,degree of differentiation,pathological type,tumor imaging density and tumor location between the two groups(P >0.05).The maximum diameter of tumor was statistically significant(P=0.001),SUVmax value was statistically significant(P=0.015).In group B(p N1 or N2),the proportion of micropapillary components was more than 5%(P = 0.001),and the SUVmax value was more than 4.65(P = 0.001).The result was statistically significant(P<0.05).The median survival time,1 and 3-year survival rates of group A were 78 months,97% and 90%respectively.The median survival time,1 and 3-year survival rates of group B were 55 months,96% and 83% respectively.The survival curve of group A was better than that of group B(P = 0.013).Univariate analysis showed that the proportion of micropapillary components > 5%,the maximum diameter of tumor and the SUVmax value of PET-CT parameters > 4.65 were significantly correlated with the survival rate of patients(P <0.05);Multivariate analysis showed that the proportion of micropapillary components >5% and SUVmax value of PET-CT parameter > 4.65 were independent prognostic factors(P < 0.05).Conclusion: The proportion of micropapillary components > 5% and the SUVmax value of PET-CT parameters > 4.65 are independent risk factors for occult lymph node metastasis in patients with clinical stage T1N0 non-small cell lung cancer.