Superior vena cava syndrome (SVCS) in children can be life-threatening. This is because the trachea (windpipe) can quickly become blocked. In adults, the windpipe is fairly stiff, but in children, it is softer and can more easily be squeezed shut. Also, a child's windpipe is narrower, so any amount of swelling can cause breathing problems. Squeezing of the trachea is called superior mediastinal syndrome (SMS). Because SVCS and SMS usually happen together in children, the two syndromes are considered to be the same.
Common symptoms include the following:
There are other less common but more serious symptoms:
The causes, diagnosis, and treatment of SVCS in children are not the same as in adults.
SVCS in children is rare. The most common cause is non-Hodgkin lymphoma. As in adults, SVCS may also be caused by a blood clot that forms during use of an intravenous catheter (flexible tube used to put fluids into or take blood out of a vein) in the superior vena cava.
A physical exam, chest x-ray, and medical history are usually all that are needed to diagnose superior vena cava syndrome in children. Even if doctors think cancer is causing SVCS, a biopsy may not be done. This is because the lungs and heart of a child with SVCS may not be able to handle the anesthesia needed. Other imaging tests may be done to help find out if anesthesia can be safely used. In most cases, treatment will begin before a diagnosis of cancer is made.
The following treatments may be used for SVCS in children:
Radiation therapy is usually used to treat a tumor that is blocking the vein. After radiation therapy, there may be more trouble breathing because swelling narrows the windpipe. A drug to reduce swelling may be given.