Abstract 2601
Background
Immune checkpoint inhibitors (ICIs) acting against CTLA-4 and PD-1 represent a strenght therapy in patients (pts) with metastatic melanoma (MM). Antineoplastic activity of ICIs through the activation of immune cells in tumor lesions raised challenge in evaluation of treatment response by imaging. Aim of this study was to compare diagnostic accuracy of different 18F-FDG PET/CT parameters (Metabolic Tumor Volume, MTV; Total Lesion Glycolisis, TLG; Maximum Standardised Uptake Value, SUVmax) to predict therapy response and clinical outcome in pts with MM treated with Ipilimumab (Ipi) and Nivolumab (Nivo) or Pembrolizumab (Pem) and to check for accuracy differences specific for the class of treatment.
Methods
57 MM pts receiving Ipi (25) or PD-1 inhibitors (Nivo 19; Pem 13) who performed a 18F-FDG PET/CT scan at the beginning (PET0) and after completion of Ipi or during anti PD-1 (PET1), were retrospectively evaluated. Response at PET1 was classified as PD, SD, PR and CR according to RECIST 1.1, EORTC criteria and by percentage change of MTV and TLG (cut off values: +43% for PD and -43% for PR, calculated by ROC analysis) of up to 5 target lesions. PET Response Evaluation Criteria for Immunotherapy (PERCIMT) were assessed alone and with the previously described parameters. Performance of each criteria at PET1 to predict pts having clinical benefit (CR, PR and SD) and no clinical benefit (PD) at 6 months since starting ICIs were assessed and correlated to time-to-progression.
Results
For Ipi pts group, best predictors of response were: variation of MTV (Sensitivity 1; Specificity 0.84; accuracy 0.96) and TLG (Se 0.89; Sp; 93.8; acc 0.92), with PERCIMT criteria for progressive disease. In anti-PD1 group overlapping predictivity values were found for EORTC, MTV and TLG (Se 0.95; Sp 1; Acc 0.97). Reliability of above parameters was also confirmed in predicting pts progression free survival at 12 and 24 months.
Conclusions
18F-FDG PET/CT performed 3 months later the first administration could predict response to ICIs and long-term patient clinical outcome. Performance of 18F-FDG PET/CT parameters and criteria in predicting response to ICIs is influenced by the class of treatment.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
Local Ethic committee.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
3630 - Results of phase 1 clinical trial of high doses of Seleno-L-methionine (SLM) in sequential combination with Axitinib in previously treated and relapsed clear cell renal carcinoma (ccRCC) patients
Presenter: Yousef Zakharia
Session: Poster Display session 3
Resources:
Abstract
2356 - Safety and Efficacy of CDX-014 , an Antibody-Drug Conjugate against T Cell immunoglobulin mucin-1 (TIM-1), in advanced Renal Cell Carcinoma
Presenter: Bradley McGregor
Session: Poster Display session 3
Resources:
Abstract
1028 - SPAZO2 (SOGUG): Outcomes and prognostic significance of IMDC intermediate prognosis subclassification in metastatic renal cell carcinoma (mRCC) in patients treated with 1st-line pazopanib (1stPz).
Presenter: Begona P. Valderrama
Session: Poster Display session 3
Resources:
Abstract
2293 - Effect of Antacid Intake on the Therapeutic Efficacy of Sunitinib (SUN) in Metastatic Renal Cell Carcinoma (mRCC) Patients (pts): a Sub-Analysis of the STAR-TOR Registry
Presenter: Katrin Schlack
Session: Poster Display session 3
Resources:
Abstract
1451 - Randomized phase 3 trial of avelumab + axitinib vs sunitinib as first-line treatment for advanced renal cell carcinoma: JAVELIN Renal 101 Japanese subgroup analysis
Presenter: Motohide Uemura
Session: Poster Display session 3
Resources:
Abstract
4399 - Overall and progression-free survival according to MSKCC scores in 1st line sunitinib treatment of metastatic renal cell carcinoma (mRCC)
Presenter: Jindrich Finek
Session: Poster Display session 3
Resources:
Abstract
1344 - Combination therapy with checkpoint inhibitors for first-line treatment of advanced renal cell carcinoma: A systematic review and meta-analysis of randomized controlled trials
Presenter: Kyaw Thein
Session: Poster Display session 3
Resources:
Abstract
3462 - A phase II trial of TKI induction followed by a randomized comparison between nivolumab or TKI continuation in renal cell carcinoma (NIVOSWITCH)
Presenter: Viktor Grünwald
Session: Poster Display session 3
Resources:
Abstract
5268 - Nivolumab (N) treatment beyond progression in a real-world cohort of patients (pts) with metastatic renal cell carcinoma (mRCC)
Presenter: Sophie Hans
Session: Poster Display session 3
Resources:
Abstract
4235 - First results of safety profile of nivolumab (NIVO) in combination with stereotactic body radiotherapy (SBRT) in II and III line of patients (pts) with metastatic renal cell carcinoma (mRCC) in NIVES Study
Presenter: Cristina Masini
Session: Poster Display session 3
Resources:
Abstract