Tumor Does my guinea pig have a tumor?

[MicoNyan]

I have a hairless guinea pig, Minmin. He is almost 3 years old.
Just this night I noticed that his skin was sagging A LOT in his belly and neck area. It's like a weight was weighing his skin down.
I felt around the loose skin to see if it was really just loose skin... but it felt like something is in them, like; a bubble.
I would like to know if anyone knows what it is. Is it a tumor? Also, his shoulder blades are really prominent but you can't see the outline of his ribs or spine.
He has access to clean water and timothy hay 24/7. He also gets his veggies.
Lately, I've noticed that he has become less active and for nearly the whole day today, he was turned around in his cage, facing the wall.
He has a harder time moving since his stomach area is dragging on the ground.
I've attached some pictures. (I had to take a picture of my camera's screen using my phone because the camera wouldn't connect to my computer; sorry for the bad quality)

 

[bpatters]

Yes, that does look like an abnormal growth, possibly a mammary tumor, possibly a fatty tumor or cyst. He needs to see a good exotic vet.

Either would probably have to be surgically removed, but have a very good prognosis in the hands of a good exotic vet.

 

[barbaramudge]

I would be getting that checked. I know nothing about skinny pigs or tumors in pigs but that looks wrong to me.

 

[piggielover200]

Poor pig! I don't have any advice but I hope he gets better soon!

 

[kimzano]

How did things turn out? Wondering if u saw the vet , and if your piggie is ok?