Novel PET Tracer Enhances Detection of Deep Vein Thrombosis and Pulmonary Embolism

A newly developed PET radiotracer has demonstrated efficacy in identifying deep vein thrombosis (DVT) in the legs and detecting whether these clots have migrated to the lungs. This advancement facilitates whole-body imaging of blood clots via a single scan, potentially expediting the diagnosis of conditions like pulmonary embolism, which is crucial for timely treatment.

Unveiled at the 2026 Annual Meeting of the Society of Nuclear Medicine and Molecular Imaging (SNMMI), the radiotracer earned the distinction of being named the SNMMI Henry N. Wagner, Jr., Image of the Year. The SNMMI annually recognizes images that highlight significant advancements in nuclear medicine and molecular imaging, which can lead to enhanced patient care through better disease detection and treatment selection.

DVT is a common condition where blood clots form in the legs and may travel to the lungs, resulting in a pulmonary embolism. The Centers for Disease Control and Prevention reports approximately 900,000 cases annually in the United States. Early detection is imperative to provide effective treatment.

Traditional imaging methods, such as venous ultrasound and CT, rely on indirect indicators, such as vein compressibility or filling defects, without directly visualizing the clot. Sangwon Han, MD, PhD of Asan Medical Center, South Korea, notes that the novel 18F-GP1 PET/CT imaging method targets activated platelets, enabling direct visualization of clots, even in difficult-to-assess areas.

In the study, researchers evaluated the diagnostic accuracy of 18F-GP1 PET/CT in detecting acute lower extremity DVT. Forty-six symptomatic patients were imaged with the new radiotracer, with results independently analyzed by three nuclear medicine physicians. The PET/CT's performance was compared against venous ultrasound, particularly for identifying clots in the thighs and evaluating clot detection rates in the calves and lungs. The radiotracer was deemed safe and well-tolerated during the study.

Results revealed that 18F-GP1 PET/CT reliably identified clots in both thigh and calf regions, and demonstrated high accuracy in detecting pulmonary embolisms occurring concurrently with DVT. Dr. Han emphasized that a single PET scan could potentially assess clots in both the legs and lungs, minimizing the necessity for multiple diagnostic tests.

Chair of the SNMMI Scientific Program Committee, Giuseppe Esposito, MD, expressed optimism regarding the radiotracer's broad applicability in thrombus detection, suggesting its potential for detecting stroke and cardiovascular diseases. Already explored in phase 2 trials, 18F-GP1 PET/CT is poised for further validation in larger phase 3 studies, aiming for integration into standard clinical practice within the next decade.

Such advancements underscore the promise of molecular imaging in transforming diagnostic practices.