This is likely a tumor. If it were a cyst or abcess, it would be filled with fluid or bacterial infection and be easy to lance or remove. Tumors have a large blood supply and are fed by lots of veins. If you try to cut it off, you may not get it to stop bleeding. This is something you need to leave alone and let a vet handle it. The question should be, is it benign or malignant. Also it is growing- as it looks pretty long. No idea if it effects the eggs or not, but I just wouldn't want to leave that up to chance personally. I've seen tumors similar to this on dogs (looks like horns), and they usually turn out to be benign, but if left and not removed, that can change quickly to being malignant.