Hi. about 2 months ago i noticed that my dominant arm is larger in width than my left. It's firmer too. I can feel like a mass i dont think, not one that can't be manipulated into making it straight anyway, and there isnt a visable lump. I sometimes get shooty pains in my lungs but only when i worry about my arm. I went to my GP a few months ago who said he would send me for a scan within 2 weeks, well it's now been over 2 months and i'm really scared. I'm 23 and i dont have much pain with it, my arm is still very mobile, sometimes i get cramps after i obsessively squeeze and play with my arm. I worry about sarcoma most of all. Can anyone help me in anyway. has anyone dealt with similar issues. Any sarcoma sufferers out there?