January 1st 2003
Venous thromboembolic disease is a common but likely underdiagnosedcondition in the cancer patient population. Timely and accuratediagnosis of venous thromboembolism is imperative due to the unacceptablemorbidity and mortality associated with a misdiagnosis.Because diagnosis of the condition based on clinical grounds alone isunreliable, physicians should select an appropriate objective diagnostictest to confirm or refute their clinical impressions. Compressionduplex ultrasound is the best initial imaging test for both suspectedupper- and lower-extremity deep venous thrombosis. Magnetic resonancevenography (MRV) is a valid alternative when ultrasound isinconclusive, but contrast venography remains the “gold standard.”Suspected pulmonary embolism should be initially evaluated by helical(spiral) computed tomography (CT) or ventilation/perfusion lungscintigraphy, the former being preferred in cases of obvious pulmonaryor pleural disease. Indeterminate studies should prompt performanceof contrast pulmonary angiography. Inferior vena cava thrombosis isalso best assessed by contrast venography, with MRV and CT reservedas alternative imaging modalities. Evidence to date suggests thatD-dimer assays remain unreliable in excluding venous thromboembolismin cancer patients. A newer latex agglutination D-dimer assay mayprove to be clinically useful in this setting.