Application Value Of ¹⁸F-FDG PET/CT Metabolic Parameters In The Prognostic Prediction Of Diffuse Large B-Cell Lymphoma

Objective Through data analysis of PET/CT imaging in 69 patients with Diffuse Large B-cell lymphoma,this paper aims to:?1?explore the value of baseline ¹⁸F-FDG PET/CT imaging metabolic parameters SUVmax,MTV and TLG in the prognosis evaluation of patients with DLBCL;?2?and to explore the differences in the prognostic value of PET/CT metabolic parameters SUVmax,MTV and TLG before and after standard first-line chemotherapy.Methods This study retrospectively analyzed 77 cases with initially diagnosed DLBCL from January 2013 to September 2018 in General Hospital of Ningxia Medical University.All patients were confirmed as diffuse large B-cell lymphoma by histopathology and immunohistochemistry,and all had been examed by ¹⁸F-FDG PET/CT scan before chemotherapy.A total of 77 patients,8cases were excluded because of abandoning treatment,transferring to hospital and following up less than 4 months.Finally,69 patients were followed up.Using SUVmax=2.5 as the threshold,the value size of ¹⁸F-FDG PET/CT imaging metabolic parameters SUVmax,MTV and TLG of 69patients with DLBCL were obtained by delineating the region of interest of the lesion and using absolute threshold method.Through outpatient follow-up and telephone follow-up,69 patients with complete case data were obtained,and the patient's age,gender,LDH level,IPI score,Ann Arbor staging,patient progression or recurrence time,and time of death were recorded.Through the above data,the patient's progression-free survival and overall survival were collected.According to Ann Arbor staging,patients were divided into stages I,II,III,and IV.According to the follow-up results,the patients were divided into the progression/relapse group and the non-progression/relapse group,including 20 patients with progression recurrence and 49 patients with non-progression recurrence.Statistical analysis was performed using SPSS22.0 software:t-test was used for comparison between the two groups;Differences among groups were compared with one-way analysis of variance,Count data comparison using chi-square test or Fisher exact probability method;P<0.05 was considered statistically significant.39 of 69 patients with DLBCL underwent¹⁸F-FDG PET/CT in the middle and late stages of treatment.The ¹⁸F-FDG PET/CT imaging metabolic parameters SUVmax2,MTV2 and TLG2 were obtained by absolute threshold method.Through above analysis we got?SUVmax%,?MTV%,and?TLG%.From the ROC curve analysis,the cutoff values of tumor recurrence/progression were predicted by SUVmax,MTV,TLG,?SUVmax%,?MTV%,and?TLG%,respectively.The survival period and the survival curve were calculated using the Kaplan-Merier method.Single and multi-factor COX regression models were used to analyze single and multiple ¹⁸F-FDG PET/CT metabolic parameters and clinical indicators.Results 1.By one-way analysis of variance,there was no significant difference in SUVmax between the four groups?F=1.521,P>0.05?.There were significant differences in MTV and TLG values among the 4 groups?P<0.05?.2.There were significant differences in MTV and TLG between the progression/relapse group and the non-progression/relapse group?P<0.05?.3.The differences of?SUVmax%,?MTV%,and?TLG%between the progression/relapse group and the non-progression/relapse group were statistically significant,respectively,P<0.05.4.In the prognostic analysis of metabolic parameters before treatment,MTV and TLG values were the prognostic factors of PFS.And SUVmax had no effect on prognosis.SUVmax,MTV,and TLG values were not the prognostic factors of OS.5.In the prognostic analysis of high-stage patients?stages III and IV?,MTV and TLG values were independent prognostic factors of PFS,and SUVmax had no effect on prognosis.6.?SUVmax%,?MTV%,?TLG%calculated before and after chemotherapy were the prognostic factors of PFS?P<0.05?;however,they were not independent factors.7.Ann Arbor staging,LDH levels,IPI scores,MTV and TLG were all prognostic factors for PFS.Ann Arbor staging,LDH level,IPI score were prognostic factors of OS.Conclusion:1.The higher Ann Arbor stage of DLBCL patients,the higher MTV and TLG values.The MTV and TLG values of progressive/recurrent group were higher than those of non-progressive/recurrent group.2.¹⁸F-FDG PET/CT imaging metabolic parameters MTV,TLG,?SUVmax%,?MTV%,?TLG%values were important prognostic factors of PFS in patients with DLBCL,while SUVmax predictive value was not significant.3.In patients with stage III and IV,MTV and TLG values were independent prognostic factors for PFS.4.Ann Arbor staging,LDH levels,and IPI scores were factors influencing the prognosis of PFS and OS in patients with DLBCL.