Tumour thrombosis and patterns of fluorine-18 fluorodeoxyglucose uptake: a pictorial review

Tumour thrombosis (TT) is a very rare but serious complication in oncologic patients. The presence of TT has a significant impact on tumour staging, treatment decisions and prognosis in many malignancies. Current diagnostic techniques show poor ability to differentiate between bland and malignant thrombi; tumour thrombi are also usually inaccessible for biopsies, making their diagnosis difficult. In recent times, fluorine-18 fluorodeoxyglucose PET/computed tomography (F-FDG PET/CT) has well established its role in oncological imaging because of the high metabolic contrast of F-FDG between malignant and normal tissue. Patients with tumour thrombi may benefit from F-FDG PET/CT imaging when TT cannot be diagnosed precisely by other conventional imaging modalities. Here we provide a pictorial review of a few common and unusual sites of tumour thrombus in different malignancies and their patterns of F-FDG uptake.