tumor :( very scared

Question
i recently found a huge lump on my 2 and a half year old female rat. it is about the size of two mentos lollies stacked on top of each other. its just behind her left front leg. i am very afraid its a tumor. i got her from a pet shop in queensland. i hold her every night and she eats a variety of everything, from fruit and veges to rat food, biscuits. lately as soon as i finish holding her and put her back in her cage she trys to jump back on my hand and is VERY eager for me to pick her back up. when i walk away she freaks out and watches me. please helllp. if its a tumor, how long will she live?

Answer
Sounds like a mammary tumor. Mammary tumors are easily removed and are pretty easy to recover from. Even leaving it, she'll probably have at least another 6 to 8 months -- until its simply too big to support. And honestly, you have to gauge her general health. If she's still very healthy despite her age, I'd encourage you to find a vet and have it removed. You may have her for another year and a half, perhaps longer!