puppy has bump on her back

Question
last week, i bought a 8 weeks old golden retriever puppy. i just noticed there is a bump on his back behind her neck around 3 days ago. it doesnt bother her, but it does for me. i tried to bring it to the vet, he shot it with some kind of medicine on her back, but it doesn't help. and the worse part is the vet didnt know exactly what was it. please help me as i am so worried. thanks

Answer
Herianto,

Did the puppy come with a microchip or have vaccines done?  The lump can be caused by either of those things and is nothing to worry about, unless it gets bigger.

I'm not sure why a vet would inject a lump, usually they take a sample of cells by aspirating the lump and looking at the cells under a microscope.  If the lump does not go down and there was not a microchip or vaccines given in that area I would go back and request a "Fine Needle Aspirate" from the vet.  

It's unlikely it is a tumor because the pup is so young, but it's good to make sure.

Good Luck,

Laura