ABSTRACT
BACKGROUND: Nivolumab, an anti-programmed death-1 (PD-1) antibody, is administered in patients with previously treated non-small cell lung cancer. However, little is known about the established biomarker predicting the efficacy of nivolumab. Here, we conducted a preliminary study to investigate whether 18F-FDG-PET/CT could predict the therapeutic response of nivolumab at the early phase. METHODS: Twenty-four patients were enrolled in this study. 18F-FDG-PET/CT was carried out before and 1 month after nivolumab therapy. SUVmax, metabolic tumour volume (MTV), and total lesion glycolysis (TLG) were calculated. Immunohistochemical analysis of PD-L1 expression and tumour-infiltrating lymphocytes was conducted. RESULTS: Among all patients, a partial metabolic response to nivolumab was observed in 29% on SUVmax, 25% on MTV, and 33% on TLG, whereas seven (29%) patients achieved a partial response (PR) based on RECIST v1.1. The predictive probability of PR (100% vs. 29%, p = 0.021) and progressive disease (100% vs. 22.2%, p = 0.002) at 1 month after nivolumab initiation was significantly higher in 18F-FDG on PET/CT than in CT scans. Multivariate analysis confirmed that 18F-FDG uptake after administration of nivolumab was an independent prognostic factor. PD-L1 expression and nivolumab plasma concentration could not precisely predict the early therapeutic efficacy of nivolumab. CONCLUSION: Metabolic response by 18F-FDG was effective in predicting efficacy and survival at 1 month after nivolumab treatment.
Subject(s)
Antibodies, Monoclonal/therapeutic use , Antineoplastic Agents/therapeutic use , Carcinoma, Non-Small-Cell Lung/diagnostic imaging , Lung Neoplasms/diagnostic imaging , Positron Emission Tomography Computed Tomography , Aged , Aged, 80 and over , Carcinoma, Non-Small-Cell Lung/drug therapy , Female , Fluorodeoxyglucose F18 , Humans , Lung Neoplasms/drug therapy , Male , Middle Aged , Nivolumab , Predictive Value of Tests , RadiopharmaceuticalsABSTRACT
BACKGROUND/AIM: L-[3-18F]-α-methyl tyrosine (18F-FAMT) positron emission tomography (PET) has a high specificity for detecting malignant lesions. However, the usefulness of therapeutic monitoring of 18F-FAMT PET against advanced human neoplasms remains unclear. Here, we evaluated 18F-FAMT PET clinical significance regarding therapy response and outcome after systemic chemotherapy in patients with advanced lung cancer, compared to 18F-FDG PET. PATIENTS AND METHODS: All patients with untreated advanced lung cancer received 18F-FAMT PET and 18F-FDG PET before and 4 weeks after one cycle of chemotherapy. Metabolic response (MR) was defined according to the PERCIST guideline. RESULTS: Ninety-five patients were eligible for analysis on both PET scans. The histological type included 87 non-small cell lung cancers and 8 small-cell lung cancers. Post-treatment maximal standardized uptake values (SUVmax) and MR on 18F-FAMT PET were correlated with tumor response. In all patients, post-treatment SUVmax of 18F-FDG and 18F-FAMT PET and MR of 18F-FAMT PET were statistically significant prognostic markers for predicting poor outcome by univariate analysis. Multivariate analysis confirmed that MR on 18F-FAMT PET was a significant independent prognostic factor. CONCLUSION: MR on 18F-FAMT PET may be a potential parameter to predict the prognosis after first-line chemotherapy in patients with advanced lung cancer.
