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Why does my 2-year-old dwarf hamster have a black lump under her arm?
Updated on September 23rd, 2025
Pet's info: Small Animal | Unknown - Small Animal | Female | unspayed | 2 years old | 0 lbs
Hi! I am going to call the vet tomorrow when they open but I wanted to get an idea of what be on my female hamster. She's a dwarf russian and she has a huge black lump under her arm. She turned 2yrs old this month and it doesn't seem to bother her at all since she's still eating, drinking, and playing. I was just wondering what it could be
1 Answer
Most Helpful Answer
Answered By Andrea M. Brodie, DVM
Veterinarian
Published on July 13th, 2018
Lumps can alwys be a tumor, a cyst, or an Abscess. When it is black and solid, it could be melanoma, when it is black and fluctuating, it could be a hematoma.
Unfortunately without a photo and the ability to palpate the lump I cannot say which type it might be.
However your vet will be able to tell, and if necessary he can determine the type of mass with a fine needle aspirate where a tissue sample is harvested with a very thin needle. Treatment varies depending on diagnosed condition.
Unfortunately without a photo and the ability to palpate the lump I cannot say which type it might be.
However your vet will be able to tell, and if necessary he can determine the type of mass with a fine needle aspirate where a tissue sample is harvested with a very thin needle. Treatment varies depending on diagnosed condition.
1Pet Parents found this answer helpful