Tumor, cyst, abscess? Please help

Although I already know the answer, I'd like some advice on one of my girls. She has this growth on her hind leg that ballooned up overnight. I got her for free, so it's not like I'd take a hit if I euthanized her, but she's super sweet and one of my favorites, so I was wondering if there were any alternatives. I've only had her for about 3 weeks. The girl I got her from said she had had an injury to that leg, but I didn't see any signs of major scarring or anything that would indicate muscle damage that would impair her walking. She's always kind of lifted the leg when walking, but didn't display any discomfort when I palpated her leg.

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I appreciate any and all input, even if it is to just break out my co2 chamber :'( Thanks.

Def tumor.

What did the previous owner say that the original injury was from? The skin color doesn't really look different in the pictures so I doubt it's an abscess but it could be a cyst under the skin. However, I don't think it's normal for them to spring up overnight either. If you really would rather keep her then I would get a vet opinion to see if there's anything they can do.

Well the reason the lady got rid of her was because she had an older female rat that didn't get along with the new girl. She said it was an injury from a fight. But I'm thinking maybe it was the start of a tumor that she just attributed to a fight injury.

I was just really surprised to see it pop up so quickly in one so young. My bf had rats when he was younger, and had one with a golf ball sized tumor grow in the course of 1 month. But they were much older, definitely nearing the end of life.

I would honestly take her to the vet and see. If it's an infection they might be able to deal with it. If it's a tumor that grew that fast (that's usually a bad sign), I doubt there's anything they can do because it's probably spread to other areas like the lungs.

Ok I'll give my vet a call tomorrow, see if there's anything to be done. On a related note, would there be any issues feeding her off? Lol I don't see why there would be any problems unless it was filled with pus maybe. Or if the tumor part couldn't pass through the throat.

I mentioned that we might have to put her down, and my mother in law was like, "What? You can't feed her to your snake, what if he gets sick?" Just wanted to double check. Thanks

Hopefully someone else can comment on that. I personally wouldn't unless I knew for sure what it was and if it was safe. If it's something that would cause a lot of bacteria to build up then I probably wouldn't feed it to one of my snakes. I couldn't imagine that I would enjoy eating infected meat though so maybe it's just me. That's something else you could ask the vet too.