Wondering about a fluid filled cyst on skin

[kgrey]

My 18 year old persian has a large lump on her shoulder. It first appeared 5 years ago. The vet has been watching it...saying it was a fatty tumor...nothing to worry about. She has never had any vaccines in that location. Over the past year it has grown to almost 3" x 1" x 1".
Recently it began to ooze fluid. In cleaning it I found that I could drain the fluid from it. The fluid was clear w/light yellow color until the last bit which had some blood in it. There was no smell to it at all. 3 days later the sagging skin began to fill again with fluid. Again I have drained it.
Any idea what this may be? Any idea on how the vet would treat it?
My Mandi is only 5 lbs (has been this tiny her whole life) and fragile with age. I do not think she could tolerate surgery. I don't want to put her through a lot of painful procedures. She has another lump on her cheek. That one is about 1/2 inch round.

[OsnobunnieO]

Your kitty needs to see a vet. You may not need to have her undergo surgery, but she at least needs to be looked at.

If she's had this one lump for five years but it suddenly grew in size, something is wrong. And to top it off, its oozing! This is leaving her vulnerable to infection getting in if it isn't cleaned and closed properly. It may also be painful to her.

And the second lump on her cheek should be checked out as well. Even if she doesn't undergo surgery, there may be some way to help her.