I found a lump on my son's arm. They did blood work and it was fine. They don't know what it is?

I'm wondering what are the chances if it's malignant or benign tumor?

If its near the forearm area it could be just some hardened tissue, nothing to worry about.

The things you need to look for are any changes to the lump or surrounding area in a short amount of time.

Also go get a biopsy, where they can take a sample of it and test it

Where exactly on his arm? And how big is it?

could it be a sist i had one its a lump its round and hard

"Fine" implies it's benign, but it might not be a tumor at all. What does the doctor say?

I had a lump on my arm when I was young. It was in my lymp node and we where told it was cat scratch fever. Which caused the lymp node to swell

I always believe in getting a second opinion...from a reliable source. Don't rely on an Internet diagnosis.

First opinions have been known to be wrong. Why gamble with your son's health?

Get a second opinion.. It should not be there.. You got a "We don't know" That answer won't do for my child. Any lump or bump needs attention.

...skin can develop numerous carbuncles and bumps, 99% of the time they are non cancerous. If they bother him, usually they are burned out with an electric pencil under local anesthetic

is this the tuberculosis shot..?
if it is, it takes about 3-4 days to be gone
if he still has that lump or bubble looking in his arm after 3-4 days then he has a problem

My 2 yr old had one on her leg that got bigger and bigger so they sent us for an MRI come to find out her body just reacted to a shot she had 1 month before. They watched it and it wasn't connected to anything it was above the muscle. We kept an eye on it with dr supervision and it went away. Has he ahd any shots or anything the hurt his arm. If your not satisfied with the dr results get a 2nd opinion can't hurt might be simple as a cyst.