Clinicopathological Features,Prognostic Factor Analysis And Survival Nomogram Of Patients With Double Primary Cancers Involving Lung Cancer

Objective: To retrospectively analyze the clinicopathological and prognostic features of patients with double primary cancers(DPCs)involving lung cancer.And we aimed to develop and validate a survival nomogram to predict individual overall survival(OS)for patients with DPCs involving lung cancer.Methods: We screened 103 patients with DPCs involving lung cancer among 9288 patients diagnosed lung cancer and admitted to the oncology department of Shengjing Hospital from Jan.2016 to Dec.2021.All patients were divided into synchronous double primary cancers(s DPCs)and metachronous double primary cancers(m DPCs)according to the time interval of cancer occurrence(6 months).Then patients with m DPCs were divided into the lung cancer first(LCF)and other cancer first(OCF)according to the first organ.The clinicopathological and prognostic features of the above-mentioned groups of patients were analyzed.The prognostic factors were determined by Univariate and multivariate analysis using Cox proportional hazards regression model.All prognostic factors were combined to construct a nomogram to predict the OS.Then the predictive performance of nomogram was validated by the consistency index(C-index)and calibration plots.Results: A total of 9288 lung cancer patients were screened,of which 103 experienced DPCs involving lung cancer(1.11%).Among all patients,35(33.98%)developed s DPCs,68 developed m DPCs.Among m DPCs patients,18(26.47%)had lung cancer diagnosed first(LCF),50(73.53%)had other cancers diagnosed first(OCF).The mean age at first diagnosis was 60.05 ± 10.47 years and the peak age at first diagnosis was 60-69 years.Breast cancer(27.18%),colorectal cancer(22.33%)and urological tumors(18.45%)were the most common second primary cancers for all patients.Breast cancer(34.7%)and digestive system tumors(33.3%)were the most common second primary cancers in patients with lung adenocarcinoma(n=72)and urologic tumors(33.3%)were the most common second primary cancers in patients with squamous lung cancer(n=21)(P=0.011).Patients in s DPCS group were more often treated with double cancer resection surgery and patients in m DPCs group were more often treated with a single cancer resection surgery + drug regimen(P=0.001).A significantly higher proportion of patients in s DPCs group underwent chemotherapy than those in the m DPCs group(P=0.017).The median interval between the occurrence of two cancers was 38 months,with a mean interval of68.93±7.68 months.Patients in the LCF group had a shorter mean interval between cancers(P=0.019)and a significantly higher proportion of patients with stage I and II lung cancer than those in the OCF group(P=0.041).Patients with LCF were more likely to undergo double cancer resection,whereas patients with OCF were more likely to undergo single cancer resection + drug therapy(P=0.044).a significantly higher proportion of patients with LCF underwent radical lung cancer surgery than those with OCF(P=0.001).a significantly higher proportion of patients with OCF underwent radiotherapy than those with LCF(P=0.049).Tumor stage IV(P=0.008)and absence of radical lung cancer surgery(P=0.028)were independent risk factors that significantly affected overall patient PFS.Pathological type of squamous carcinoma(P=0.048),tumor stage IV(P=0.001),treatment choice of single cancer resection plus drug therapy(P<0.001),drug therapy alone(P=0.002),failure to undergo radical lung cancer surgery(P=0.014)and chemotherapy(P=0.042)were independent risk factors that significantly affected overall patient OS.Overall patients had a median survival time of 37.97 months and a mean survival time of 64.09 ± 7.88 months.3-year and 5-year survival rates were 50.9% and 35.9%,respectively.There was no statistical difference between the concurrent and isochronous groups in median survival time(37.55 months vs 36.24 months),mean survival time(62.96 months vs 56.31 months),3-year(50.4% vs 50.2%),and 5-year survival rate(37.4%vs 34.8%)(P=0.687).We used these independent risk factors for OS of all patient to construct nomogram.The C-index of the nomograms to predict OS were 0.734(95%CI:0.667-0.801).The calibration plots demonstrated the good performance of the survival nomogram.Conclusion: 1.11% of patients with lung cancer had a second primary cancer.Breast,colorectal,and urinary system were the most common extra-pulmonary sites for patients with DPCs involving lung cancer.m DPCs were more common than s DPCs.There was no statistically significant difference in prognosis between m DPCs and s DPCs patients.Compared with the other cancer that occurred concurrently,lung cancer was the main cause of death for patients with DPCs involving lung cancer.In cases where only one tumor is eligible for surgery,drug therapy alone is a better option compared to a single cancer surgery plus drug therapy regimen.In addition,we developed and validated a survival nomogram to predict individual OS for patients with DPCs involving lung cancer.