摘要：
目的 分析弥漫性大B细胞淋巴瘤(DLBCL) PET/CT显像最大摄取值变化率(△SUVmax％)和C-MYC基因对DLBCL化疗后预后的判断价值,寻找合适的PET/CT检查时间.方法 2010年9月至2016年2月间171例病理证实的DLBCL患者[男87例,女84例,平均年龄(50.66±2.56)岁],包括化疗早期(1、2周期,60例)、化疗中期(3、4周期,55例)及化疗后期(5、6周期,56例)显像组.于化疗前1周及相应化疗周期结束后17～ 21 d行18F-脱氧葡萄糖(FDG) PET/CT显像,勾画感兴趣区,计算△SUVmax％[(SUVmax前-SUVmax后)/SUVmax前×100％],采用Deauville五分法对患者评分,采用原位荧光杂交(FISH)检测C-MYC基因.随访6～71个月,计算无进展生存(PFS)期.采用x2检验、Spearman相关、单因素方差分析及Kaplan-Meier法分析数据.结果 171例DLBCL中42例C-MYC基因重排,有或无C-MYC基因重排患者在年龄、Ann Arbor分期、国际预后指数(IPI)评分、血清乳酸脱氢酶(LDH)水平及治疗反应方面差异有统计学意义(x2值:6.139～98.339,均P＜0.05).化疗早、中、后期显像组△SUVmax％最佳界值分别为62.5％、87.0％和92.0％,按≥界值和＜界值各分为2组,组间PFS差异均有统计学意义(x2值:21.983 ～33.674,均P＜0.001);C-MYC基因重排阳性患者的PFS明显差于阴性患者(x2值:53.649～61.899,均P＜0.001).△SUVmax％与C-MYC基因重排间呈负相关(rs=-0.801,P＜0.001).化疗早期、中期、后期显像组间△SUVmax％差异有统计学意义(F=6.509,P＜0.01),Deauville评分结果差异有统计学意义(F=19.897,P＜0.001);但化疗中期显像与后期显像间2个指标差异均无统计学意义(P＞0.05).结论 不同化疗周期△SUVmax％和C-MYC基因重排对DLBCL均有预测价值,化疗中行PET/CT检查最早选择在化疗1周期结束时,最晚选择在化疗4周期结束时.%Objective To evaluate the prognostic value of the maximum standardized uptake value decrease proportion (△SUVmax％) on 18F-fluorodeoxyglucose (FDG) PET/CT imaging and C-MYC gene in diffuse large B cell lymphoma (DLBCL),and to find the optimal time of PET/CT imaging.Methods From September 2010 to February 2016,171 patients (87 males,84 females,average age:(50.66±2.56) years)with pathologically confirmed DLBCL were analyzed.18F-FDG PET/CT were performed before and after different courses of chemotherapy (60 patients in early phase which means 1 and 2 courses;55 patients in medium phase,3 and 4 courses;56 patients in late phase,5 and 6 courses).The region of interest (ROI) was drawn and the △SUVmax％ was calculated.Patients were evaluated with Deauville 5-point scale.Fluorescence in situ hybridization (FISH) was employed to detect C-MYC gene.Patients were followed up for 6-71 months,and progression-free survival (PFS) was calculated.x2 test,one-way analysis of variance,Kaplan-Meier analysis and Spearman correlation analysis were used to analyze the data.Results There were 42 C-MYC gene rearrangement of 171 DLBCL patients.Age,Ann Arbor stage,international prognostic index (IPI) score,serum lactate dehydrogenase (LDH) level and therapeutic response were different between patients with C-MYC gene rearrangement and those without rearrangement (x2:6.139-98.339,all P＜0.05).The optimum cutoff values of the △SUVmax％ were 62.5％,87.0％ and 92.0％ respectively in the early,medium and late phases of chemotherapy.Patients with △SUVmax％ ≥≥ 62.5％,≥ 87.0％ or ≥ 92.0％ and normal C-MYC gene showed longer PFS (x2 values:21.983-61.899,all P＜0.001).The △SUVmax％ was negatively correlated with C-MYC gene rearrangement (rs =-0.801,P ＜ 0.001).Significant differences were found in △SUVmax％ (F=6.509,P＜0.01) and Deauville 5-point scale (F=19.897,P＜0.001) among patients in early,medium and late phases.No Significant differences were shown between medium and late phases (P＞0.05).Conclusion △SUVmax％ in the different phases of chemotherapy and C-MYC gene rearrangemeut have better values for predicting the prognosis of DLBCL,and 18F-FDG PET/CT imaging should be performed between 1 course and 4 courses of chemotherapy.
