18F-FLT/FET PET-CT in Treatment Response Evaluation

Abstract

A variety of radiolabeled amino acids have been used for imaging brain tumors. FET and MET have been the most widely used amino acid tracers. Amino acid tracers can be used for detection, tumor grading, targeting biopsy, and evaluation of response. Fluorothymidine (FLT) is a nucleoside thymidine analog. Assessment of treatment response in gliomas is very challenging. Amino acid tracers have been proven to be more appropriate. FET PET/CT offers high diagnostic power in this scenario. FET PET with additional dynamic data analysis was significantly superior to conventional MRI in discriminating tumor recurrence from post-therapeutic changes. The present literature in neuroimaging using PET highlights the ability of amino acid PET to quantify biological responses to treatment and allows its application to monitor patients to identify early disease relapse and response to treatment. However, the diagnostic impact of amino acid PET needs to be compared with a variety of advanced MR imaging techniques to develop the most accurate and useful multi-modal biomarkers possible.