Clinicopathological Characteristics And Survival Analysis Of Different Gene Mutations In Non-small Cell Lung Cancer(EGFR)

Objective:Lung cancer is one of the leading causes of cancer-related deaths in the world,with a five-year survival rate of only 15 percent,and it kills more people each year than breast,pancreatic,colon and prostate cancers combined.The most common types of lung cancer are non-small cell lung cancer(NSCLC),The common subtypes of NSCLC include lung adenocarcinoma,squamous cell carcinoma and large cell carcinoma,among which lung adenocarcinoma and squamous cell carcinoma are the most common subtypes of lung cancer in clinic.Epidermal growth factor receptor(EGFR)is a transmembrane protein with cytoplasmic kinase activity that carries important growth factor signals from the extracellular environment into the cell and is expressed in more than 50%of patients with non-small cell lung cancer.In Asian populations,EGFR mutation is one of the important reference indicators for assessing NSCLC disease progression.This study mainly analyzed the clinicopathological characteristics of different EGFR gene mutation types in non-small cell lung cancer,explored the role of different clinicopathological characteristics in different EGFR mutation types,and analyzed the survival rate of different EGFR mutation types.Methods:A total of 254 cases of non-small cell lung cancer patients who had undergone EGFR testing at the First Affiliated Hospital of Anhui Medical University from 2017 to April 2019 were collected for paraffin-embedded tissue pathology.The EGFR gene mutation status was detected by the Amplification refractory mutation system(ARMS)method,and the EGFR gene mutation detection was performed by the EGFR gene mutation detection kit.The mutation status and clinicopathological data were analyzed statistically,and the cases and clinicopathological characteristics of EGFR gene mutation status were discussed.Kaplan meier curves were used to calculate the effect of EGFR mutant and wild type on progression-free survival and overall survival in each subgroup.Results:1. A total of 133(52.36%)EGFR gene mutations were detected in 1,254 patients.Among them,48 were male and 85 were female;47 were younger than 60 years old,and 86 were?60 years old;55 were smoking patients and 78 were non-smokers;123were lung adenocarcinomas and 10 were squamous cell lung cancers;3 were screened Exon18 G719X mutation;58 cases were screened for Exon19 deletion mutation;6 cases were screened for Exon20 insertion mutation;1 case was screened for Exon20 S768I mutation,1 case was screened for Exon20 T790M mutation;54 cases were screened for Exon21 L858R mutation;Exon21 L861Q mutations were screened in 4 cases;Exon21deletion mutations were screened in 4 cases(see Figure 1).In addition,two patients had multiple site mutations,one with Exon18 G719X and Exon21 L816Q mutations,and one with Exon18 G719X and Exon20 insertion mutations.Among the 133 patients with EGFR mutations,L85R and Exon19-del were the most common mutation types,accounting for 40.60%and 43.61%,respectively.EGFR mutations occur mainly in women and have no history of smoking.2. A total of 254 patients were included in this study,including 87 male patients and48 EGFR mutations with a mutation rate of 49.48%;127 female patients and 85 EGFR mutations with a mutation rate of 66.93%.There is a statistical difference between the two.Significance(c~2=6.930,P=0.008).A total of 78 patients under 60 years of age,47cases of EGFR mutations,a mutation rate of 60.26%;a total of 176 patients over 60years of age,86 cases of EGFR mutations,a mutation rate of 48.86,there is no significant difference between the two(c~2=2.812,P=0.094).There were 115 patients with no smoking history and 78 EGFR mutations with a mutation rate of 67.83%.There were 139 patients with smoking history and 55 EGFR mutations with a mutation rate of39.57%.The difference was statistically significant(c~2=20.146).,P=0.000).There were 178 patients with lung adenocarcinoma and 123 patients with EGFR mutations,with a mutation rate of 69.10%;76 patients with lung squamous cell carcinoma and 10patients with EGFR mutations,with a mutation rate of 13.16%.P=0.000).There were133 patients in stage Ia-IIIa,74 patients with EGFR mutation,and the mutation rate was55.64%;121 patients in stage IIIb+IV,59 patients with EGFR mutation,and 48.76%,the difference between the two was not statistically significant(c~2=3.812,P=0.124).There were 120 patients without lymph node metastasis,62 patients with EGFR mutation,and the mutation rate was 51.67%;134 patients with lymph node metastasis,71 patients with EGFR mutation,and 52.99%mutation rate,the difference between the two was statistically significant(c~2=2431 P=0.165).3.A total of 118 of the 254 patients died.There were 45 deaths in the EGFR mutation-positive group with a mortality rate of 33.83%;73 deaths in the EGFR mutation-negative group with a mortality rate of 60.33%.The difference was statistically significant(c~2=17.882,P=0.000).4.Kaplan-meier survival curve was used to calculate the relationship between EGFR mutation positivity and OS.The survival time of the EGFR mutation positive group was not determined,but the total survival time of the EGFR mutation negative group was 44months,and the difference between the two groups was statistically significant(P=0.001).A total of 119 patients were surgically removed from all 254 patients,who were divided into the EGFR mutation-positive group(83)and the EGFR mutation-negative group(26).By the end of follow-up,a total of 37 of the 119 patients had relapsed,including 21 in the EGFR mutation-positive group with a recurrence rate of 25.31%,and 11 in the EGFR mutation-negative group with a recurrence rate of42.31%.Kaplan-meier survival curve was used to calculate the relationship between EGFR mutation positivity and PFS.The median PFS of the EGFR mutation-positive group was 48 months,while that of the EGFR mutation-negative group was 20 months,showing a statistically significant difference between the two groups(P=0.002).A total of 135 patients were unsurgically removed from all 254 patients,who were divided into the EGFR mutation positive group(50 patients)and the EGFR mutation negative group(85 patients).By the end of follow-up,a total of 85 cases had progressed in the two groups,including 33 cases in the positive group,with a progress rate of66.0%.In the negative group,there were 58 cases,with a progression rate of68.24%.Kaplan-meier survival curve was used to calculate the relationship between EGFR mutation positivity and DFS.The EGFR mutation positive group was 43 months old,while the EGFR mutation negative group was 33 months old,and the difference between the two groups was statistically significant(P=0.0078).Conclusion1.The mutation rate of EGFR gene was 52.36%.2.Exon21 L858R and exon19-deletion mutations were the most common mutation types,accounting for 40.60%and 43.61%,respectively.3. EGFR mutations mainly occur in female patients with no smoking history.4. The EGFR mutation positive group had longer OS,PFS and DFS than the EGFR mutation negative group.