What Causes Lump Between The Ribcage Causing Pain While Breathing?

I have a lump in between my rib cage its tender to the touch and recently been giving me problems when I lean over and starting to be very uncomfortable sometimes hurts when I breathe like its tight?! went to the doctors got xrays and sonogram done everything normal but they check my organs and not the spot I was talking bout now they spending me to a surgeon any ideas