基线18F-FDG PET/CT在转移性恶性黑色素瘤患者预后评估中的价值

目的 探讨治疗前18F-氟脱氧葡萄糖（FDG）PET/CT代谢参数在转移性恶性黑色素瘤（MM）患者预后评估中的价值。 方法 回顾性分析2011年8月至2018年12月在南京大学医学院附属鼓楼医院确诊为转移性MM的47例患者的临床资料，其中男性20例、女性27例，中位年龄59（23~86）岁。对所有患者行化疗、免疫或靶向治疗。随访时间为0.5~53.6个月。黑色素瘤特异性生存期（MSS）和无进展生存期（PFS）分别定义为从18F-FDG PET成像到患者病死的时间和疾病进展或病死的时间。所有患者在治疗前均行18F-FDG PET/CT检查，测量最大标准化摄取值（SUV_max），并以SUV>40% SUV_max的体素边界作为临界值，分别测量并计算全身肿瘤代谢体积（MTV）和全身病灶糖酵解总量（TLG）。采用受试者工作特征（ROC）曲线分析得出PET参数的最佳临界值，并以SUV_max、全身MTV和全身TLG临界值为界分别将患者分为2组，共6组。采用Kaplan-Meier法及Log-rank检验预测2组间MSS和PFS的差异。采用单因素分析法评估PET参数和临床变量的预后意义。采用Cox比例风险模型多因素分析PET参数是否为MSS和PFS的独立预后危险因素。 结果 SUV_max、全身MTV和全身TLG的最佳临界值分别为10.86、8.12 cm3和91.45。全身MTV和全身TLG以临界值为界的2组患者PFS的差异均有统计学意义（χ2=5.04、5.02，均P<0.05）；SUV_max和全身TLG以临界值为界的2组患者MSS的差异均有统计学意义（χ2=10.22、4.38，均P<0.05）。单因素分析结果表明，血清乳酸脱氢酶水平≥245 U/L、淋巴结转移、SUV_max>10.86和全身TLG>91.45是MSS的预后危险因素；M1期、全身MTV>8.12 cm3和全身TLG>91.45是PFS的预后危险因素。多因素分析结果表明，SUV_max>10.86是MSS的独立预后危险因素。 结论 18F-FDG PET/CT代谢参数SUV_max是转移性MM患者病死的最佳预测因素，而全身MTV和全身TLG对转移性MM患者的预后具有一定的预测价值。

Prognostic value of pretreatment 18F-FDG PET/CT in patients with metastatic malignant melanoma

Objective To demonstrate whether 18F-FDG PET/CT metabolic parameters could predict prognosis in patients with metastatic maligant melanoma (MM). Methods A retrospective analysis was conducted on a dataset composed of 47 patients who were newly diagnosed with metastatic MM and currently undergoing pretreatment 18F-FDG PET/CT in the Affiliated Hospital of Nanjing University Medical School, Nanjing Drum Tower Hospital from August 2011 to December 2018. Of 47 patients, 20 were male, 27 were female and median age 59 (23?86) years. All patients were treated with chemotherapy, immunotherapy or targeted therapy and follow-up time was 0.5 to 53.6 months. Melanoma-specific survival (MSS) and progression-free survival (PFS) were defined as the time from 18F-FDG PET/CT imaging to the patient's death and the patient's death or progression of the disease, separately. All patients underwent 18F-FDG PET/CT imaging before treatment.The maximum standardized uptake value (SUV_max) was measured. Whole-body metabolic tumor volume (MTV) and whole-body total lesion glycolysis (TLG) were measured automatically and SUV>40% SUV_max voxel boundary was used as threshold. The optimal thresholds of PET parameters were obtained using the receiver operating characteristic (ROC) curve, and the patients were divided into two groups separately according to the optimal thresholds of SUV_max, whole-body MTV and whole-body TLG and six groups were obtained. The difference of MSS and PFS between the two groups were predicted by Kaplan-Meier method and Log-rank test. Univariate analysis was conducted to evaluate the prognostic value of PET parameters and clinical variables. The Cox proportional risk model multivariate analysis was used to determine whether the PET parameters can act as independent prognostic risk factors for MSS and PFS. Results The cut-off values for SUV_max, whole-body MTV, and whole-body TLG were 10.86, 8.12 cm3, and 91.45, respectively, as shown in the ROC curve analysis. The PFS was significantly different in two groups divided by optimal thresholds of whole-body MTV or whole-body TLG, separately (χ2=5.04, 5.02; both P<0.05). Similarly, the MSS was significantly different in two groups divided by optimal thresholds of SUV_max or whole-body TLG, separately (χ2=10.22, 4.38; both P<0.05). The univariate analysis results were as follows: the serum lactate dehydrogenase level≥245 U/L, lymphatic metastasis, SUV_max>10.86 and whole-body TLG>91.45, which were associated with predictors of MSS. M l stage, whole-body MTV>8.12 cm3 and whole-body TLG>91.45, which were associated with PFS. The multivariate analysis results showed that SUV_max>10.86, proving its potential as an independent prognostic risk factor for MSS. Conclusion The 18F-FDG PET/CT metabolic parameter SUV_max was the best predictive marker in metastatic MM patients, whole-body MTV and whole-body TLG helped for the prognosis of metastatic MM patients.