Clinical value of 3'-deoxy-3'-[18F]fluorothymidine-positron emission tomography for diagnosis, staging and assessing therapy response in lung cancer

Abstract

Lung cancer has the highest mortality rate of any tumour type. The main driver of lung tumour growth and development is uncontrolled cellular proliferation. Poor patient outcomes are partly the result of the limited range of effective anti-cancer therapies available and partly due to the limited accuracy of biomarkers to report on cell proliferation rates in patients. Accordingly, accurate methods of diagnosing, staging and assessing response to therapy are crucial to improve patient outcomes. One effective way of assessing cell proliferation is to employ non-invasive evaluation using 3'-deoxy-3'-[18F]fluorothymidine ([18F]FLT) positron emission tomography [18F]FLT-PET. [18F]FLT, unlike the most commonly used PET tracer [18F]fluorodeoxyglucose ([18F]FDG), can specifically report on cell proliferation and does not accumulate in inflammatory cells. Therefore, this radiotracer could exhibit higher specificity in diagnosis and staging, along with more accurate monitoring of therapy response at early stages in the treatment cycle. This review summarises and evaluates published studies on the clinical use of [18F]FLT to diagnose, stage and assess response to therapy in lung cancer.

Fluorinated carbohydrates for18F-positron emission tomography (PET)

“…Further studies carried out between 2003 and 2016 have consistently reported that [ 18 F]-FLT (65) has a higher specificity but lower uptake when compared to 2-[ 18 F]-FDG (1). 182 This suggests that whilst less [ 18 F]-FLT (65) actually makes it into the cell, the likelihood of the tumour being malignant is higher if uptake occurs. [ 18 F]-FLT (65) therefore has an important role to play in the early diagnosis of malignant lesions, particularly if further structural modifications lead to improved cellular uptake.…”

Molecular Imaging of Renal Cell Carcinoma in Precision Medicine

“…FLT is a thymidine analog that can be transported into cells and phosphorylated by thymidine kinase-1. Phosphorylated FLT cannot participate in subsequent deoxyribonucleic acid (DNA) synthesis and remains in cells due to the hydroxyl group at the 5′ end of the thymidine being replaced by 18 F. 105 Uptake of 18 F-FLT by tumor cells could reflect the rate of DNA synthesis and cell proliferation. 106 18 F-FLT PET/CT has been used for differentiation of benign and malignant tumors, assessment of treatment response, and prediction of prognosis in different malignancies.…”

Hematopoiesis in the spleen after engraftment in unrelated cord blood transplantation evaluated by 18F-FLT PET imaging

“…The radiopharmaceutical 3′-deoxy-3′- 18 F-fluorothymidine ( 18 F-FLT), a thymidine analog used in positron emission tomography (PET) imaging, is a surrogate indicator of deoxyribonucleic acid synthesis [ 22 ]. 18 F-FLT PET is a valuable method for assessing hematopoietic proliferative activity in the bone marrow and extramedullary space [ 20 , 23 , 24 ].…”