A Retrospective Cohort Study Of Family History And Prognosis Of Lung Cancer

Background:lung cancer was the most dangerous malignancy in the world for human health and life.In 2012,there were 1.8 million new lung cancer cases and 1.59 million deaths in the world,accounting for 12.8%and 19.4%of all cancer cases.As one of the most common malignant tumors,lung cancer was the leading cause of cancer death among men and the second leading cause of cancer death among women worldwide.Among Chinese population,Lung cancer had being the leading cause of cancer death both among men and women.Although the diagnosis and treatment of lung cancer had achieved great progress in recent years,the overall prognosis of lung cancer remained abysmal,as the 5-year survival rate of lung cancer being only 21.2%in the United States and even lower in China,as 19.7%.Therefore,lung cancer had become an important health problem in the world.The definition of family history of cancer was that one or several members of a family had a malignant tumor with the same anatomical position,with the characteristic of familial disease.Previous studies had shown that,family history of cancer as a reflection of a certain genetic background,could be used as a method to measure the influence of genetic factors.It was closely related to the prognosis of malignant tumors such as breast cancer and colorectal cancer in some studies,but there were not many studies about the association between family history and prognosis of lung cancer.Therefore,our study aimed to explore the association between family history of malignant tumors with the prognosis of lung cancer,so as to evaluate the influence of family history on lung cancer prognosis,to guide the lung cancer treatment and improve the survival of patients with lung cancer.Objective:Our study was a retrospective cohort study.Based on the lung cancer cases of the first affiliated hospital of Nanjing medical university and the affiliated tumor hospital of Nanjing medical university,we systematically analyzed the association between family history of malignant tumor and prognosis of lung cancer,include the influence family history of lung cancer and other malignant tumor family history on the prognosis for lung cancer patients,and discussed the interaction between family history and other clinical pathological factors on the influence of lung cancer prognosis,to explain the differences in the survival of lung cancer patients with a family history of malignant tumors and those with no family history,to guide the decision-making of improving the prognosis of lung cancer.Methods:A total of 1010 new cases of lung cancer diagnosed with histopathology or cytology in Jiangsu province from September 2002 to July 2014 were systematically analyzed.All patients were subjected to epidemiological survey,clinicopathological data collection and follow-up survey.The last follow-up survey was in December 2017.All data was recorded by the Epidata software,and the data was sorted and managed by SPSS software.All the statistical analyses were carried out by R software.Kaplan-Meier method was used to calculate the survival rate,and log-rank test was used to compare the survival differences of different subgroups.In multifactorial analysis,cox regression analysis was used to assess the association between family history of malignant tumor and the prognosis of lung cancer,to calculate the risk ratio（Hazard Rate,HR）and 95%Confidence Interval.In addition,several baseline variables were analyzed in this study,we investigated the effect of family history of malignant tumor on prognosis of lung cancer in different subgroups.All analysis was performed by double-sided,P<0.05 was considered as statistical significance.Results:Of the 1010 cases of lung cancer,701（69%）were male and 599（59%）had a history of smoking.The amount of smoking among men was 577,with a smoking rate of 82.3%.There were 570 patients with lung adenocarcinoma,accounting for 56.4%of the total cases.In our study,489 patients died of lung cancer,and the median survival time was 39.6 months（95%CI:33.7⁴8.4）,3-year survival rate was 51.8%,and 5-year survival rate was 41.1%.332 cases（32.9%）had a family history of malignant tumors,88 cases（8.4%）were patients with family history of lung cancer.In univariate analysis,Men,smoking statue,high pathological TNM stage,none-surgery and none-adjuvant therapy all increased the risk of death from lung cancer（P<0.05）.In cox regression analysis,we found that patients with a family history of malignant tumor had higher mortality risk than those without family history（multiple factors adjusted HR=1.27,95%CI:1.05-1.53,P=0.012）.The mortality risk of first-degree relatives with other malignant tumor family history was higher than that of patients without family history（multiple factors adjusted HR=1.31,95%CI:1.07-1.60,P=0.010）.The risk of death from lung cancer increased as the number of patients with first-degree relatives increased.Compared to patients without family history,the risk of death was significantly increased by 24 percent in patients with 1 and 2 first-degree relatives with cancer,patients with three or more first-degree relatives with cancer increased the risk of death by 163 percent.Also,the results of stratified analysis between subgroups based on baseline variables showed that under different smoking conditions,there was a statistically significant difference in prognosis of lung cancer patients who had a family history of malignant tumor(P_{heterogeneity}=0.039).And interaction analysis showed that the family history and smoking status of malignant tumor affect the survival of patients with lung cancer jointly(P_interaction=0.024).Conclusion:Our study was based on a Chinese population tumor cohort,we found that gender,pathological stage,pathological type and cancer therapy were important indicators for the prognosis of lung cancer,which was consistent with previous literature reports.The family history of malignant tumor affected the prognosis of lung cancer,and was an important factor for the prognosis of lung cancer,which was of great significance for the clinical treatment of lung cancer patients.