FDG-PET/CT for venous thromboembolic disorders: Preliminary results

Objectives To evaluate FDG-PET/CT as a potential molecular imaging modality for venous thromboembolism (VTE) in a prospective, observational proof-of-concept pilot study.

Methods Patients with proven deep venous thrombosis or pulmonary embolism (DVT+/PE+) or disproven DVT or PE (DVT-/PE-) were eligible. Exclusion criteria (non-inclusion) were: Age < 50 years, pregnant or lactating women, previous DVT or PE, known malignancy, or unobtainable consent.

Results Eleven patients were included: Two women and nine men with a mean age of 65 years (range 50-78 years); seven DVT+, four DVT-, four PE+, and no PE- (four patients were both DVT+ and PE+). The duration of symptoms prior to inclusion was 2-7 days for the DVT+ patients, and 2 weeks-5 months for the PE+ patients. All seven DVT+ patients showed abnormal FDG uptake in the corresponding leg, while none of the DVT- patients or the PE+ patients showed abnormal FDG uptake in the venous vasculature.

Conclusions Our results substantiate the potential role of FDG-PET/CT in VTE, especially for DVT with all DVT+ being positive and all DVT- being negative. The results from lung scan positive patients are likely due to non-specificity of the latter modality in determining the age of the clots. Therefore, the results from FDG-PET/CT images could actually represent the true nature of older and inactive PE. Although further studies are warranted for definite clarification, FDG-PET/CT may give rise to a paradigm shift in both diagnostic and therapeutic strategies for the management of VTE by screening the entire body for VTE and underlying occult malignancies, and by differentiating acute from chronic VTE.