I have a lump on the sternal/medial end on the right side of my collarbone. It is directly on the collarbone, possibly on the sternoclavicular joint, not above or around. It is in the exact same place as the bone in my left collar bone, basically on the joint, but on the right side it sticks out and is much more prominent. It could be bone, maybe it has always been like this and I've just not noticed as bones can be asymmetrical I guess, or maybe it's a swollen joint. Obviously I will have to go to the doctor, but I was just wondering if anybody else has experience the same and has had a diagnosis.