Background and purpose:Next generation sequencing-identified genetic alterations of diffuse large B cell lymphoma(DLBCL)and baseline SUVmax detected by 18F-FDG PET/CT were correlated with patients'prognosis.However,their relationship and the associations with R-CHOP response of DLBCL are still unclear.This study aimed to analyze the association bewteen genetic alterations and 18F-FDG PET/CT SUVmax and their correlations with clinicopathological characteristics and R-CHOP response of DLBCL.Methods:A total of 225 cases of primary DLBCL detected by next generation sequencing using 481 lymphoma gene panel and examined by 18F-FDG PET/CT before treatment between 2022 and 2023 were collected.This study was approved by the Ethics Committee of Fudan University Shanghai Cancer Center(Ethical No.:050432-4-2307E)and acquired the informed consent of the patients.The translocations of BCL2,BCL6 and MYC were identified by fluorescence in situ hybridization.The clinicopathological characteristics and the PET/CT scan after R-CHOP chemotherapy were collected.Results:Finally,191 patients were enrolled in this study.The frequency of MYD88 mutation,TP53 mutation,copy number variations of CDKN2A/2B,CD79B mutation in the 191 DLBCL patients were 24.6%,27.2%,32.5%and 16.8%,respectively.The range of baseline SUVmax was 5.10-63.10(24.44±10.70,median 22.80).The baseline SUVmax of MYD88L265P DLBCL was significantly higher than that of MYD88 wild type(P=0.039).There were no significant associations of SUVmax with other gene alterations including TP53 mutation,CDKN2A/B loss,CD79B mutation,KMT2D mutation,TNFAIP3 mutation,B2M mutation,EZH2 mutation,BTG1/2 mutation,CREBBP mutation,gene translocations of MYC,BCL2 and BCL6.The higher SUVmax before treatment was correlated with higher serum lactate dehydrogenase(LDH)level(P=0.012)and non-germinal center B-cell-like(non-GCB)DLBCL(P=0.040).However,there was no significant association of SUVmax with R-CHOP response(P=0.714).TP53 mutation was significantly associated with the poor response of R-CHOP(P=0.001)and was an independent predictor of non-complete metabolic response(non-CMR).TP53 mutation combined with Ann Arbor stage,International Prognostic Index(IPI)score and serum LDH level could better predict R-CHOP response than each factor alone.Conclusion:MYD88L265P DLBCL had higher baseline 18F-FDG PET/CT SUVmax.The baseline SUVmax was not associated with R-CHOP response.However,TP53 mutation was significantly correlated with poor response of R-CHOP in DLBCL patients.TP53 mutation combined with clinicopathological characteristics could better predict R-CHOP response.The associations of gene alterations and SUVmax with prognosis of DLBCL patients needed to be explored in the future.

Background and purpose:Next generation sequencing-identified genetic alterations of diffuse large B cell lymphoma(DLBCL)and baseline SUVmax detected by 18F-FDG PET/CT were correlated with patients'prognosis.However,their relationship and the associations with R-CHOP response of DLBCL are still unclear.This study aimed to analyze the association bewteen genetic alterations and 18F-FDG PET/CT SUVmax and their correlations with clinicopathological characteristics and R-CHOP response of DLBCL.Methods:A total of 225 cases of primary DLBCL detected by next generation sequencing using 481 lymphoma gene panel and examined by 18F-FDG PET/CT before treatment between 2022 and 2023 were collected.This study was approved by the Ethics Committee of Fudan University Shanghai Cancer Center(Ethical No.:050432-4-2307E)and acquired the informed consent of the patients.The translocations of BCL2,BCL6 and MYC were identified by fluorescence in situ hybridization.The clinicopathological characteristics and the PET/CT scan after R-CHOP chemotherapy were collected.Results:Finally,191 patients were enrolled in this study.The frequency of MYD88 mutation,TP53 mutation,copy number variations of CDKN2A/2B,CD79B mutation in the 191 DLBCL patients were 24.6%,27.2%,32.5%and 16.8%,respectively.The range of baseline SUVmax was 5.10-63.10(24.44±10.70,median 22.80).The baseline SUVmax of MYD88L265P DLBCL was significantly higher than that of MYD88 wild type(P=0.039).There were no significant associations of SUVmax with other gene alterations including TP53 mutation,CDKN2A/B loss,CD79B mutation,KMT2D mutation,TNFAIP3 mutation,B2M mutation,EZH2 mutation,BTG1/2 mutation,CREBBP mutation,gene translocations of MYC,BCL2 and BCL6.The higher SUVmax before treatment was correlated with higher serum lactate dehydrogenase(LDH)level(P=0.012)and non-germinal center B-cell-like(non-GCB)DLBCL(P=0.040).However,there was no significant association of SUVmax with R-CHOP response(P=0.714).TP53 mutation was significantly associated with the poor response of R-CHOP(P=0.001)and was an independent predictor of non-complete metabolic response(non-CMR).TP53 mutation combined with Ann Arbor stage,International Prognostic Index(IPI)score and serum LDH level could better predict R-CHOP response than each factor alone.Conclusion:MYD88L265P DLBCL had higher baseline 18F-FDG PET/CT SUVmax.The baseline SUVmax was not associated with R-CHOP response.However,TP53 mutation was significantly correlated with poor response of R-CHOP in DLBCL patients.TP53 mutation combined with clinicopathological characteristics could better predict R-CHOP response.The associations of gene alterations and SUVmax with prognosis of DLBCL patients needed to be explored in the future.