How to tell if hamster lump is abscess or tumor?

Does anyone know? My 1.5 year old female campbell's dwarf hamster has a large red lump on her tummy, we are taking her to the vet next week to make sure, but does anyone have advice?

I don't think there's anyway of telling really, you just need a vet to confirm it so you are doing the right thing by taking your hamster. If it puts your mind at ease, i found a large red lump on my rat, gizmo, just under one of his paws. I took him to the vet and they just cut it off and now he is fine. Is your hamster still eating and drinking and is it still his usual self? If he is then the lump possibly isn't much to worry about but your vet will be able to say for definate. Good luck and keep us posted.

Thanks, she's going to the dr. on tuesday. Yes, she is acting normal....eating, drinking, and running around happy like usual. She's peeing normal too...she just did on my bed! ewwww time to change the sheets...

lol, i take that as a good sign then, like i said, probably nothing to worry about if she is not acting strange but best to be safe than sorry. :)