Andrei Iagaru, Postdoctoral Faculty Sponsor
PURPOSE: We investigated the ability of baseline 2-deoxy-2-[18F]fluoro-D-glucose PET/CT parameters, acquired before the start of immunotherapy, to predict development of hyperprogressive disease (HPD) in melanoma patients. We also evaluated the diagnostic performances of ratios of baseline and first restaging PET/CT parameters to diagnose HPD without information of the tumor growth kinetic ratio (TGKR) that requires pre-baseline imaging before baseline imaging (3 timepoint imaging).PROCEDURES: Seventy-six patients who underwent PET/CT before and approximately 3months following initiation of immunotherapy were included. PET/CT parameters, including metabolic tumor volume (MTV) for all melanoma lesions and total measured tumor burden (TMTB) based on irRECIST, were measured from baseline PET/CT (MTVbase and TMTBbase) and first restaging PET/CT (MTVpost and TMTBpost). The ratios of MTV (MTVpost/MTVbase, MTVr) and TMTB (TMTBpost/TMTBbase, TMTBr) were calculated.RESULTS: MTVbase of HPD patients (n=9, TGKR ?2) was larger than that of non-HPD (n=67, TGKR <2) patients (P<0.05), and HPD patients demonstrated shorter median overall survival (7 vs. more than 60months, P<0.05). The area under the curve (AUC) of MTVbase (?155.5ml) to predict the risk of HPD was 0.703, with a sensitivity of 66.7% and specificity of 81.2%. The AUCs of MTVr (?1.25) and TMTBr (?1.27) to diagnose HPD without information of TGKR were 0.875 and 0.977 with both sensitivities of 100%, and specificities of 79% and 83.9%, respectively.CONCLUSIONS: Patients at high risk of developing HPD could not be accurately identified based on baseline PET/CT parameters. The ratios of baseline and first restaging PET/CT parameters may be helpful to diagnose HPD, when patients do not undergo pre-baseline imaging.
View details for DOI 10.1007/s11307-020-01526-4
View details for PubMedID 32789649
View details for Web of Science ID 000568290500424
View details for Web of Science ID 000568290500428
The purpose of this study was to investigate the prognostic value of whole-body metabolic tumor volume (MTV) and other metabolic tumor parameters, obtained from baseline and first restaging 18F-FDG PET/CT scans in melanoma patients treated with immune checkpoint inhibitors (ICIs).Eighty-five consecutive melanoma patients (M, 57; F, 28) treated with ICIs who underwent PET/CT scans before and approximately 3 months after the start of immunotherapy were retrospectively enrolled. Metabolic tumor parameters including MTV for all melanoma lesions were measured on each scan. A Cox proportional hazards model was used for univariate and multivariate analyses of metabolic parameters combined with known clinical prognostic factors associated with overall survival (OS). Kaplan-Meier curves for patients dichotomized based on median values of imaging parameters were generated.The median OS time in all patients was 45 months (95% CI 24-45 months). Univariate analysis demonstrated that MTV obtained from first restaging PET/CT scans (MTVpost) was the strongest prognostic factor for OS among PET/CT parameters (P 0.0001). The median OS in patients with high MTVpost (??23.44) was 16 months (95% CI 12-32 months) as compared with more than 60 months in patients with low MTVpost (23.44) (P =?0.0003). A multivariate model including PET/CT parameters and known clinical prognostic factors revealed that MTVpost and the presence of central nervous system lesions were independent prognostic factors for OS (P?=?0.0004, 0.0167, respectively). One pseudoprogression case (1.2%) was seen in this population and classified into the high MTVpost group.Whole-body metabolic tumor volume from PET scan acquired approximately 3 months following initiation of immunotherapy (MTVpost) is a strong prognostic indicator of OS in melanoma patients. Although the possibility of pseudoprogression must be considered whenever evaluating first restaging PET imaging, it only occurred in 1 patient in our cohort.
View details for DOI 10.1007/s00259-020-04792-0
View details for PubMedID 32296882