TY - JOUR T1 - Correlation between PD-L1 expression and glucose metabolic indexes of <sup>18</sup>F-FDG PET/CT imaging of patients with lung adenocarcinoma. JF - Journal of Nuclear Medicine JO - J Nucl Med SP - 1244 LP - 1244 VL - 59 IS - supplement 1 AU - Yan Cui AU - Yaming Li AU - Xuena Li Y1 - 2018/05/01 UR - http://jnm.snmjournals.org/content/59/supplement_1/1244.abstract N2 - 1244Objectives: Lung cancer is the malignant tumor with the highest morbidity and mortality in China. Lung adenocarcinoma is the most common pathological type among lung cancer. Surgery, chemotherapy and molecular targeted therapy are main treatments for lung adenocarcinoma currently. However, most patients were in late stage of disease and lost the opportunity of surgery when diagnosed accompanying with resistance to chemotherapy and targeted therapy, leading to a low overall survival rate. Tumor invasion, recurrence and metastasis were the main causes of death in patients with lung adenocarcinoma. In recent years, immune escape has been considered to be the key factor contributing to tumor resistance and progression. The immune escape could be acquired by the inhibition of immune cells proliferation and function through the binding of Programmed death-ligand 1 (PD-L1) expressed by tumor cells to Programmed death-1 (PD-1) expressed by immune cells. Long-lasting clinical response and improved prognosis have been observed in the checkpoint blockade antibody therapy in patients with advanced lung cancer. But there was still no “gold standard” for selecting suitable population which may benefit from checkpoint blockade antibody. Multiple mechanisms were involved in the immune escape of tumors. Studies have shown that tumor immune escape was closely related to tumor glucose metabolism reprogramming. The purpose of this research was to investigate the correlation between PD-L1 expression and tumor glucose metabolism reflected by 18 F-fluorodeoxyglucose (18F-FDG) positron emission tomography /computed tomography(PET/CT), providing evidence for screening suitable patients for PD-L1 antibody utilizing 18F-FDG PET / CT. Methods: 89 cases who underwent 18F-FDG PET / CT with suspicious malignant lung lesion and confirmed as lung adenocarcinoma with pathological diagnosis were enrolled. The expression of PD-L1 was evaluated by immunohistochemistry. The correlation between the expression of PD-L1 and maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), total lesion glycolysis (TLG) which were glucose metabolic indexes of 18F-FDG PET / CT were investigated. The discrepancy of tumor size, age, gender, TNM stage between different PD-L1 expression groups were also discussed. Results: Based on the immunohistochemical analysis of PD-L1, 89 patients were divided into negative expression group (53 cases) and positive expression group (36 cases). The tumor size, SUVmax and TLG of PD-L1 negative group were 23.5±10.4mm, 5.3±3.9, 7.6(3.7, 21.1), respectively; The tumor size, SUVmax and TLG of PD-L1 positive group were 30.9 ± 15.0 mm, 11.4 ± 4.1 and 28.6 (14.0, 50.3), separately. There were statistical significant differences in TNM stage, tumor size, SUVmax and TLG between PD-L1 negative and positive groups (P &lt;0.05). Conclusions: Higher level of glucose metabolism was observed in PD-L1 positive expression of lung adenocarcinoma compared with that in negative ones. The expression of PD-L1 was closely related to the glucose metabolism which can be reflected by 18F-FDG PET/CT and thus this can provide basis for screening suitable patients for clinical PD-L1 antibody through 18F-FDG PET / CT. ER -