Usefulness of 18F-α-Methyltyrosine PET for Therapeutic Monitoring of Patients with Advanced Lung Cancer

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 (SUV_max) and MR on ¹⁸F-FAMT PET were correlated with tumor response. In all patients, post-treatment SUV_max 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.