Abstract 5255
Background
PD-1/PD-L1 blockades have shown promising antitumor activity in clinical trials of advanced nasopharyngeal carcinoma (NPC). Being the most wildly used molecular imaging in clinic, 18F-FDG PET/CT provides multiple information of tumor biology. In this study, we investigated the association of PD-L1 expression with 18F-FDG uptake and clinical features in patients with NPC.
Methods
84 patients were initially histopathologically diagnosed with NPC between December 2016 and March 2019. All tissue specimens and PET/CT images were collected before any treatment. The PD-L1 antibody we used in this investigation was SP263 (Ventana, USA). High PD-L1 expression in tumor cells (TC) or tumor-infiltrating immune cells (TIIC) was defined as ≥ 50% of corresponding cells with membranous staining.
Results
The values of tumor SUVmax and TLG in patients with positive TC PD-L1 expression were significantly higher than those of negative TC PD-L1 expression (SUVmax: 10.3±4.1 vs. 6.9±3.2; P < 0.001; TLG: 77.7±64.5 vs. 35.0±20.5; P < 0.001), while the SUVmax values and TLG in patients with positive TIIC PD-L1 expression is lower than those of negative TIIC PD-L1 expression (SUVmax: 7.0±3.4 vs. 9.7±4.1; P = 0.011; TLG: 29.1±14.4 vs. 71.3±61.2; P = 0.001). Univariate analysis showed that the expression of PD-L1 in TC was associated with tumor T stage (P = 0.044) but not with serum Epstein-Barr virus (EBV) load (P = 0.816). On the other hand, the expression of PD-L1 in TIIC was related to both T stage (P = 0.028) and serum EBV load (P = 0.003). In multivariate logistic regression analysis, PD-L1 expression in TC was positively associated with tumor SUVmax (P = 0.003) and TLG (P = 0.001), while PD-L1 expression in TIIC was negatively associated with SUVmax (P = 0.038) and serum EBV load (P = 0.025). Through the ROC curve, the SUVmax cut-off value of 6.7 and the TLG cut-off value of 41.3 can be used to predict the PD-L1 status in TC with an accuracy of 78.6% and 71.4%, while the SUVmax cut-off value of 7.2 can be used to predict the PD-L1 status in TIIC with an accuracy of 72.6%.
Conclusions
18F-FDG uptake with NPC lesions were positively correlated with PD-L1 expression in TC and negatively correlated with PD-L1 expression in TIIC. 18F-FDG PET / CT imaging may be useful for predicting the PD-L1 status in patients with NPC.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
3930 - Safety profile of tepotinib in patients with advanced solid tumors: pooled analysis of phase I and II data
Presenter: Thomas Decaens
Session: Poster Display session 1
Resources:
Abstract
5373 - Drug-drug interaction profile of tepotinib with CYP3A and P-gp substrates
Presenter: Juergen Heuer
Session: Poster Display session 1
Resources:
Abstract
5455 - Bioavailability of tepotinib: impact of omeprazole and food
Presenter: Juergen Heuer
Session: Poster Display session 1
Resources:
Abstract
2618 - Tislelizumab Exposure-Response Analyses of Efficacy and Safety in Patients with Advanced Tumors
Presenter: Chi-Yuan Wu
Session: Poster Display session 1
Resources:
Abstract
2563 - Population Pharmacokinetics of Tislelizumab in Patients with Advanced Tumors
Presenter: Chi-Yuan Wu
Session: Poster Display session 1
Resources:
Abstract
2021 - The Addition of Metformin to Systemic Anticancer Therapy
Presenter: Jung Han Kim
Session: Poster Display session 1
Resources:
Abstract
5243 - Growth modulation index (GMI) as a comparative measure of clinical activity of larotrectinib versus prior systemic treatments in adult and pediatric TRK fusion cancer patients
Presenter: Antoine Italiano
Session: Poster Display session 1
Resources:
Abstract
598 - Analysis of the overall survival and main surrogates used for FDA approvals in solid and hematological malignancies.
Presenter: Maria Kleniewska-Wieczor
Session: Poster Display session 1
Resources:
Abstract
5381 - Comparison of intratumoral docetaxel exposure in cancer patients between nanoparticle entrapped docetaxel (CPC634) and conventional docetaxel (Cd): the CriTax study
Presenter: Ruben Van Eerden
Session: Poster Display session 1
Resources:
Abstract
2935 - Correlation of progression free survival-2 and overall survival in solid tumors
Presenter: Paul Mainwaring
Session: Poster Display session 1
Resources:
Abstract