Treatment Monitoring of Immunotherapy and Targeted Therapy Using F-18-FET PET in Patients with Melanoma and Lung Cancer Brain Metastases: Initial Experiences

Galldiks, Norbert; Abdulla, Diana S. Y.; Scheffler, Matthias; Wolpert, Fabian; Werner, Jan-Michael; Huellner, Martin; Stoffels, Gabriele; Schweinsberg, Viola; Schlaak, Max; Kreuzberg, Nicole; Landsberg, Jennifer; Lohmann, Philipp; Ceccon, Garry; Baues, Christian; Trommer, Maike; Celik, Eren; Ruge, Maximilian I.; Kocher, Martin; Marnitz, Simone; Fink, Gereon R.; Tonn, Joerg-Christian; Weller, Michael; Langen, Karl-Josef; Wolf, Jürgen und Mauch, Cornelia (2021): Treatment Monitoring of Immunotherapy and Targeted Therapy Using F-18-FET PET in Patients with Melanoma and Lung Cancer Brain Metastases: Initial Experiences. In: Journal of Nuclear Medicine, Bd. 62, Nr. 4: S. 464-470

Abstract

We investigated the value of O-(2-F-18-fluoroethyl)-L-tyrosine ((18) F-FET) PET for treatment monitoring of immune checkpoint inhibition (ICI) or targeted therapy (TT) alone or in combination with radiotherapy in patients with brain metastasis (BM) since contrast-enhanced MRI often remains inconclusive. Methods: We retrospectively identified 40 patients with 107 BMs secondary to melanoma (n = 29 with 75 BMs) or non-small cell lung cancer (n = 11 with 32 BMs) treated with ICI or TT who had F-18-FET PET (n = 60 scans) for treatment monitoring from 2015 to 2019. Most patients (n = 37;92.5%) had radiotherapy during the course of the disease. In 27 patients, 18 FFET PET was used to differentiate treatment-related changes from BM relapse after ICI or TT. In 13 patients, F-18-FET PET was performed for response assessment to ICI or TT using baseline and follow-up scans (median time between scans, 4.2 mo). In all lesions, static and dynamic F-18-FET PET parameters were obtained (i.e., mean tumor-to-brain ratios [TBR], time-to-peak values). Diagnostic accuracies of PET parameters were evaluated by receiver-operating-characteristic analyses using the clinical follow-up or neuropathologic findings as a reference. Results: A TBR threshold of 1.95 differentiated BM relapse from treatment-related changes with an accuracy of 85% (P = 0.003). Metabolic responders to ICI or TT on F-18-FET PET had a significantly longer stable follow-up (threshold of TBR reduction relative to baseline, >= 10%;accuracy, 82%;P = 0.004). Furthermore, at follow-up, time to peak in metabolic responders increased significantly (P = 0.019). Conclusion: F-18-FET PET may add valuable information for treatment monitoring in BM patients treated with ICI or TT.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Medizin
• Themengebiete: 600 Technik, Medizin, angewandte Wissenschaften > 610 Medizin und Gesundheit
• ISSN: 0161-5505
• Sprache: Englisch