Hemorrhagic pulmonary metastases
Hemorrhagic pulmonary metastases are those which tend to be complicated by pulmonary hemorrhage within them, resulting in characteristic imaging appearances. Metastases of some tumor histologies are more likely to hemorrhage -- knowledge of this can help refine the differential diagnoses.
Pathology
Hemorrhage is mostly thought to be due to fragility of neovascular tissue that leads to a rupture of the vessel.
Recognized types generally tend to have high vascularity within them and include
- angiosarcoma - metastatic angiosarcoma to the lungs
- choriocarcinoma - metastatic choriocarcinoma to the lungs
- renal cell carcinoma
- melanoma
Radiographic features
CT chest
If there is a peri-tumoral hemorrhage this may be seen as a nodule or mass which is surrounded by a halo of ground-glass opacity (CT halo sign) or an ill-defined fuzzed-out margin.
Differential diagnosis
For a suspected nodule or mass giving a CT halo sign - see differential for a CT halo sign.
See also
