Prognostic Factors Of Second Primary Non-Small Cell Lung Cancer In SEER Database

Purpose: Multiple primary lung cancer(MPLC)has been previously widely reported with the first study published in 1975.It refers to the independent occurrence of primary lung cancers,as defined by Martini and Melamed and the ACCP criteria in Shen et al Based on the definition of multiple primary lung cancer,second primary lung cancer(SPLC)refers to a specific kind of multiple primary lung cancer that second unrelated lung cancer occurred after the diagnosis of initial primary lung cancer(IPLC).The overall incidence of second primary lung cancer has been estimated to be 1% to 2% perpatient-year.Another recent study found that the risk of developing second primary lung cancer was relatively high in patients with initial primary lung cancer.However,for patients with initially primary lung cancer(IPLC),there is a subsequent risk of developing second primary lung cancer(SPLC).And the risk of developing another lung cancer in patients with successfully cured small cell lung cancer(SCLC)has been reported to b 2-14% peryear.Moreover,because of the increasing rate of postoperative follo w-up surveillance of patients with primary lung cancer,second primary lung cancer has been profoundly studied.There have been some studies on prognosis risk factors for second primary lung cancer.However,there is a paucity of research on risk factors and nomogram for second primary non-small cell lung cancer.Th is study aimed to establish an effective prognostic nomogram for second primary non-small cell lung cancer(NSCLC).Methods:Date of patients diagnosed with second primary lung cancer between 2010-2015 were extracted from the SEER database,and patients were firstly randomly grouped using the R software in a modeling group and a validation group.In the modeling group,Univariate Cox regression analysis was performed,and variables with significant factors(P<0.05)were introduced into the multivariate Cox analysis to screen for independent factors affecting prognosis,and the results were shown as the Hazard ratio(HR)and 95%confidence interval(CI),and used it to constructed a Nomogram survival prediction model.Then in the validation group,Concordance Index(C-Index),Area Under the operating Curve(AUC),receiver Operating characteristic Curve ROC curve)were used to evaluate the differentiation of the model.The accuracy of the model was evaluated by calibration curves in the modeling group and validation group.Results: A total of 22978 patients with second primary lung cancer from 2010 to 2015were screened.The age,gender,race,marital status,year of diagnosis,primary Site,Grade,histological type,laterality,therapy,tumor size,the number of regional lymph nodes examined,surgery and vital status of the patients were extracted and analyzed.The results showed that age,sex,grade,marital status,AJCC TNM 7th,histological type,tumor size,the number of regional lymph nodes examined,therapy and surgery were considered to be prognostic factors of OS.Significant independent factors were integrated to create the nomogram.By calculating the total score and comparing it to the highest possible score,it was possible to obtain the predicted 3-and 5-year OS.C-indexes of the established nomogram were 0.771(95%CI(0.769,0.773))in the modeling group,which showed an ideal model discrimination ability.calibration plots of 3-and 5-year OS also proved the good performance of the established nomogram.The nomogram with reliable performance was developed to predict 3-and 5-year OS rates.Conclusions: Age,sex,grade,marital status,AJCC TNM 7th,histological type,tumor size,the number of regional lymph nodes examined,therapy and surgery were considered to be prognostic factors of the second primary NSCLC.We developed a nomogram that can predict OS for patients with second primary NSCLC.This practical prognostic tool may help clinicians in treatment planning.