I have a really big lump about size between tennis ball and golf ball lump at the very top of my under arm right next to my arm pit and it s hard but it is making my fingers tingle just my little finger and the two next to it, it feels like not enough blood getting to it I went to hospital and was told I have to have a scan but they said something about a bone cutting of my blood supply and they told me a name for it but iv forgotten can you tell me what it sounds like it could be and is it dangerous