The Correlated Investigation Between The Serum Levels Of Pyruvate Kinase M2 And 18F-FDG PET/CT In Patients With Primary Lung Cancer

Objective:To measure the expression levels of serum PKM2 protein in patients with primary lung cancer using enzyme-linked immunosorbent assay(ELISA),to investigate the correlation between serum levels of PKM2 and 18F-FDG PET/CT Imaging parameters in patients with primary lung cancer,and to analyze their effects in the diagnosis and treatment of primary lung cancer,so that to improve the efficiency of the diagnosis and treatment for lung cancer.Methods:From July 2019 to November 2020,60 patients with primary non-small cell lung cancer(Lung cancer group)who were treated in our hospital and underwent 18F-FDG PET/CT Imaging in the Department of Nuclear Medicine were chosen and their serum samples were collected,at the same time,the serum samples from 30 healthy population(Control group)were collected as control.Enzyme-linked immunosorbent assay(ELISA)was used to measure the expression levels of PKM2 in serum samples of all subjects.Maximum standardized uptake value(SUVmax),tumor metabolic volume(MTV),total lesion glycolysis(TLG)and other imaging parameters from the 18F-FDG PET/CT imaging of lung cancer patients were analyzed.Furthermore,the relationship between serum PKM2 expression levels and 18F-FDG PET/CT imaging parameters in lung cancer were investigated.Result:1.The serum PKM2 concentration of the Lung cancer group was 16.49±2.96ng/ml,while the serum PKM2 concentration of the Control group was 11.44±1.23ng/ml.The serum PKM2 concentration in the Lung cancer group was significantly higher than that in the Control group(P<0.001).2.The serum PKM2 concentration in the Lung cancer group was positively correlated with the SUVmax of the primary tumor focus(r=0.414,P=0.00l),and it was weakly correlated with the TLG of the primary tumor focus(r=0.292,P<0.05).However,there was no correlation between the serum PKM2 concentration with the MTV of primary tumor focus,and the SUVmax,TLG and MTV of metastasis in Lung cancer group(P>0.05).3.According to TNM staging,these lung cancer patients are divided into Early group(28 cases,stage Ⅰ-Ⅱ)and Late group(32 cases,stage III-IV).The serum PKM2 levels are 15.51±2.69ng/ml,17.90±2.98ng/ml respectively,which is significantly higher in the Late group than that in the Early group(P<0.05).The SUVmax and TLG of the primary tumor focus in the Early group were significantly lower than those in the Late group(P<0.05),while the MTV of the primary tumor focus in the two groups was no statistically significant difference(P>0.05).4.These lung cancer Patients were divided into Metastasis group(28 cases)and Non-metastasis group(32 cases).The serum level of PKM2 was 17.57±3.29ng/ml in Metastasis group and 16.10±2.73ng/ml in Non-metastasis group,with no significant difference(P>0.05).The TLG of the primary tumor focus in the Metastasis group was higher than that in the Non-Metastasis group,and the difference was statistically significant(P<0.05).However,the difference between the two groups for the SUVmax and MTV of the primary tumor focus was no statistically significant(P>0.05).5.According to the histological types,these lung cancer patients was divided into Squamous cell carcinoma group(23 cases,14 cases of metastasis)and Adenocarcinoma group(37 cases,14 cases of metastasis).The serum PKM2 level was 18.35±2.48ng/ml and 15.82±3.03ng/ml in the Squamous cell carcinoma group and Adenocarcinoma group respectively,the difference between the two groups was statistically significant(P=0.001).The SUVmax,TLG and MTV of primary tumors focus were 9.72±6.20,4.69±4.25,136.73±230.26,29.66±64.27 and 17.03±14.32,7.56±12.70 in the Squamous cell carcinoma group and Adenocarcinoma group respectively,and the differences between the two groups were statistically significant(P<0.05).However,there was no statistically significant difference between the two groups for the metastasis SUVmax,MTV and TLG(P>0.05).Conclusion:1.The level of serum PKM2 in patients with primary NSCLC is significantly higher than that of healthy population.The level of serum PKM2 in patients with Early stage is significantly lower than that in patients with Late stage.It indicates that PKM2 may be involved in the occurrence and development of primary NSCLC.2.The SUVmax value and TLG value of the primary tumor focus in NSCLC patients are positively correlated with the upregulated serum level of PKM2.The SUVmax value and TLG value of the primary tumor focus can be used to predict the expression level of PKM2 and the level of glucose metabolism,and to provide a reference to formulate the treatment plans for primary NSCLC patients.3.The serum PKM2 concentration,the SUVmax value and TLG value of NSCLC patients in the Late group(stage Ⅲ-Ⅳ)were significantly higher than those in the Early group(stage Ⅰ-Ⅱ),which is profitable to patient’s clinic staging.4.There are statistical differences in PKM2,SUVmax,TLG,and MTV between Squamous cell carcinoma group and Adenocarcinoma group,which have a certain clinical value for the differential diagnosis of primary lung cancer.