The only thing your family can do now is get a specialist.
In most of the case, chemotherapy is not an option for blood vessels due to its complication, regardless it is cancerous or not (as blood supply can be cut off). Surgical removal is always the course of treatment.
Based on your information, it does not sound like a full diagnosis has been done yet. So one should be done first.
2014-10-13 18:39:06 補充:
Iris:
Read again. I said surgery is always an option. I did not say surgery may work this case.