Prognostic Value Of Metabolic Parameters Of Pretreatment ¹⁸F–FDG PET/CT In Patients With Esophageal Cancer

Objective:The ¹⁸F–Fluorine deoxidization glucose(¹⁸F–FDG)PET/CT has been clinical recognized as the certain value in predicting the diagnosis staging and therapeutic efficacy evaluation in esophageal cancer.Studies by some foreign scholars have shown that the metabolic parameters of ¹⁸F–FDG PET/CT also have certain value in predicting the prognosis of esophageal cancer.However,domestic has performed related research relatively few.The aim of the study was to investigate value of metabolic parameter of ¹⁸F–FDG PET/CT imaging in patients with esophageal cancer before treatment.Methods:From January 2012 to April 2019,115 esophageal cancer patients(87 males and 28 females,aged from 37 to 82 years,with an average pretreatment,were enrolled in this study in our hospital.All patients'primary lesions were confirmed by pathology.We use the LIFEx 4.00 software to draw the region of interest?ROI?of the esophageal cancer primary lesion and use the threshold of 40%SUV_max on ¹⁸F–FDG PET/CT images.It will be automatically calculate the Maximum standard values(SUV_max),Metabolism of Tumor Volume?MTV?,Amount of Glycolysis?TLG?,PET tumor length?PLT?of the primary lesion respectively.The compareison of differences of metabolic parameters were used two–sample t test,one–way analysis of variance,and Mann–Whitney u or Kruskal–Wallis H test.The relationship of pretreatment ¹⁸F–FDG PET/CT metabolic parameters with treatment methods,staging factors was analyzed.The optimal cutoff points of SUV_max,MTV,TLG and PLT for predicting survival were investigated by ROC curve,and divide them into high value group and low value group.Based on the patients'progression free survival?PFS?and overall survival?OS?,the Kaplan–Meier were used to perform univariate survival analysis and Cox proportional hazards model was used to analyze the prognosis relationship between gender,age,site of esophageal primary lesion,TNM stage?T stage,N stage,M stage?,pathological type,¹⁸F–FDG PET/CT metabolic parameters(SUV_max,MTV,TLG,PLT)and treatment methods of the patients with esophageal cancer.P value less than 0.05 were considered statistically significant.Results:1.Of 115 patiens,the follow-up data of 108 esophageal cancer patients?84 males and 24 females,with an average age of 63.4±8.3 years?were complete 7 patients were lost to follow–up?7/115,6.1%?.Of the 108 patients,51 had metastatic lesions?50 with lymph node metastasis,12 with distant metastasis?and 57 without metastasis.Progression free survival in 108patients,40 cases with esophageal cancer deaths 56 cases,12 cases of disease progression,median follow–up time was 40 months?range 8–95 months?,the median OS for 30 months?95%CI 24.0 to 35.9 months?,1,3,5 years OS rate are 80.5%,41.3%and 28.7%respectively,the median PFS time of 19 months?95%CI 13.2 to 24.8 months?,1,3,5 years of PFS rate were 64.8%,30.6%and 22.9%respectively.2. In this study,49 out of 108 cases of esophageal cancer patients performed surgical comprehensive treatment?surgery,surgery plus radiotherapy or chemotherapy?,in which,pure surgery in 42 cases,surgery plus chemotherapy 4 cases,surgery plus radiotherapy in 2 cases,surgery plus radiation and chemotherapy in 1 case,and 59 out of 108 cases of esophageal cancer patients performed non–operative comprehensive treatment?radiotherapy,chemotherapy and radiotherapy plus chemotherapy and other?,in which,27 cases with simple chemotherapy,14 cases of simple radiotherapy,radiotherapy plus chemotherapy of 17 cases and other 1 case).The median PFS?28 months?and median OS?51 months?of the patients in the surgical combined treatment group were both longer than those in the non–surgical combined treatment group?16 months?and median OS?22 months?,both of which were statistically significant?P=0.013,P=0.001?.3. The optimal thresholds for predicting PFS in esophageal cancer patients by PET/CT imaging parameters SUV_max,MTV,TLG and PLT in 108patients with esophageal cancer before treatment by ROC curve were 8.28,16.1 cm³,49g and 3.55cm,respectively.The values were divided into the PLT<3.55cm).Kaplan–Meier method was used to analyze the PFS survival between groups.Log–rank test was used to compare the survival difference between the two groups.The median PFS?29,24,29,35 months?was significantly longer in the low–value group than that in the high–value group patients?15,13,13,14 months?,with statistical significance?P=0.026,0.026,0.006,0.001?.4. The optimal thresholds for predicting OS in esophageal cancer patients by PET/CT imaging parameters SUV_max,MTV,TLG and PLT in 108 patients with esophageal cancer before treatment by ROC curve were 8.28,9.75cm³,53.1g and 3.65cm,respectively.The value were divided into the high–value PLT<3.65cm).Kaplan–Meier method was used to analyze the OS survival between groups.Log–rank test was used to compare the survival difference between the two groups.The median OS?34,37,44,39 months?was significantly longer in the low–value group than that in the high–value group patients?22,24,22,22 months?,with statistical significance?P=0.020,0.018,0.001,0.009?.5. Cox proportional hazards model analysis.Will be meaningful to single factor(TNM stage,N stage,M staging,treatment,SUV_max,MTV,TLG and PLT)into the Cox proportional hazards model,multivariate analysis showed that only N staging and PLT are independent prognostic factors influencing patients PFS?HR value:1.754,2.123,P=0.025,P=0.007?.Moreover TLG and treatments are independent prognostic factors for patients with OS?HR value:2.990,2.932,P=0.000,P=0.000?.Conclusions:1.Pretreatment ¹⁸F–FDG PET/CT metabolic parameters(SUV_max,MTV,TLG and PLT)are related to the survival of patients with esophageal cancer.The higher the value,the shorter the survival period.Pretreatment ¹⁸F–FDG PET/CT metabolic parameters,can predict the survival prognosis of patients with esophageal cancer.2.Among of the pretreatment ¹⁸F–FDG PET/CT metabolic parameters(SUV_max,MTV,TLG and PLT),PLT is an independent prognostic factors for PFS,and TLG is the independent prognostic factor for OS in patients with esophageal cancer.There are more valuable than SUV_max and MTV in predicting the prognosis of patients.3.TNM stage,N stage,M stage and treatment mode are related to the survival of patients with esophageal cancer.Among them,N stage is an independent prognostic factor for PFS,and treatment mode is an independent prognostic factor for OS in patients with esophageal cancer.