The superior vena cava (SVC) is a large blood vessel that carries blood from your head and upper body to your heart. SVC syndrome happens when blood flow through the superior vena cava is blocked.
SVC syndrome is an oncologic emergency, which is a serious health problem caused by the cancer itself or its treatment. Oncologic emergencies need to be treated right away.
SVC syndrome is often caused by a tumor or enlarged lymph nodes pressing on the SVC. SVC syndrome is common in lung cancer, lymphoma, breast cancers, and with other primary tumors that have spread to the chest. It can also be caused by blood clots within the SVC.
Symptoms can happen slowly or quickly. If SVC syndrome is caused by cancer, then symptoms often happen more slowly than if it is caused by blood clots. Symptoms can be:
SVC syndrome is an oncologic emergency and needs to be treated right away. It can be diagnosed through a physical exam and chest x-ray, but you may need imaging tests (CT/MRI/venography) to measure how much of the SVC is blocked.
SVC syndrome is treated based on the cause:
If you are having any symptoms of SVC syndrome listed above, call your care team right away. If you are having a hard time breathing, call 911 or go to the emergency room right away.
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