Recognition of pulmonary venous and arterial tumors has an important clinical role in identifying cause of symptomatology,
planning for interventional procedures such as surgery,
and guiding management.
Pulmonary arterial and venous tumors may be primary,
locally invasive,
or metastatic in the form of tumor emboli. These tumors can be differentiated into benign or malignant etiologies.
Benign pulmonary artery tumors include papillary fibroelastoma,
fibroma,
and leiomyoma.
Malignant primary pulmonary artery tumors include leiomyosarcoma,
spindle cell sarcoma,
rhabdomyosarcoma,
angiosarcoma,
chrondrosarcoma,
and osteosarcoma.
Benign primary pulmonary venous tumors include leiomyoma,
and papillary fibroelastoma.
Malignant primary pulmonary venous tumors include leiomyosarcoma,
and fibrosarcoma.
Most primary pulmonary vascular tumors are sarcomas,
with arterial tumors more common than venous tumors.
Burke and Virmani 1993 identified that most pulmonary arterial tumors are intimal sarcomas,
whereas pulmonary venous tumors are more often leiomyosarcomas [1].
Primary pulmonary artery sarcomas are rare cancers,
with an estimated incidence of 0.001-0.003% [6].
Involvement of the pulmonary vasculature by invading primary tumors or metastasis is more common. The most common malignancies associated with pulmonary tumoral emboli include hepatocellular carcinoma,
breast cancer,
kidney,
and lung with uncommon etiologies being osteosarcoma and prostate.
Imaging findings are usually nonspecific and may include heterogenously enhancing filling defects,
prominent pulmonary arteries,
beaded peripheral pulmonary vessels,
and peripheral wedge-shaped opacities due to pulmonary infarcts.
There are many important mimickers to these tumors which are important to distinguish.
Examples of pulmonary vascular tumor mimickers include bland thrombus,
aneurysm,
varix,
arteriovenous malformation,
and cement emboli.
On CT,
pulmonary artery sarcoma presents as a large low-density filling defect in the central pulmonary vasculature,
sometimes with expansion of the affected vessel and calcifications distinguishing them from chronic thromboembolic disease whose lesion are less likely to occupy the entire lumen of a proximal pulmonary artery,
expand the affected vessel and uncommon to calcify.
Besides,
contrast-enhanced MRI demonstrates enhancement of the intraluminal filling defect in case of sarcoma thus differentiating them from thrombus.
Dual Energy CT technology can be used to diagnose tumors of the pulmonary arterial and venous vasculature.
Dual Energy CT utilizes two separate energy sets to differentiate attenuation and provide information about tissue composition.
The use of Dual Energy and Spectral CT can act as a problem solving tool for evaluation of pulmonary venous and arterial tumors,
and can help differentiate from other non-neoplastic pulmonary vascular lesions.