Growth behind Guinea pigs ear....

Question
My daughter's 4 or 5 year old GP has had a small growth of some sort behind her left ear for some time.  I initially thought that it was a tick, as it was about the size of an engorged tick (quarter to 3/8 inch diameter) and appeared dark reddish.

Last evening, my daughter asked me to look at 'Maria' as she said the ear had some blood behind it.  The original growth is still there, but there seems to be another one that has opened up below it.  Any idea what it could be, and is it treatable?

We all thank you for your input and suggestions.
Mark

Answer
Hi Mark

To be able to know for sure what the problem is I would like to see it. However, that is clearly not possible.

The possibilities are a cancerous growth, which is unlikely due to the position on the pig's body. More likely that it is an abcess or other natural harmless lump.

Best bet is to get it checked by a vet to be on the safe side.

Andy