Hard lump on 12 year old cat

Disclaimer, I have included pictures, the last picture is a bit gross, I apologize.

Hello,

My good friend is worried about her cat and I was hoping to find some insight for her. Her cat is about 12 years old, in early september we noticed she seemed to have discomfort in her mouth. She was pawing aggressively at her mouth and even got a claw stuck once or twice. We took her to the vet, hoping they could find something but left with no answers and used a cone for a few days to keep her from harming herself. After a few days she stopped trying to paw her face. By the middle/end of september we noticed a small hard lump on her chin. That lump slowly grew to a fairly large size by november and her breath became progressively worse but we noticed she seemed happy. The growth had not affected her behavior and she was not hiding, her appetite was normal, etc. 

During early december we noticed a sort of "drool" it is dark brown in color and seemed to come from the side of her mouth where the lump is. it was during this time she began hiding and insisted on only eating wet food (no more dry food). We discussed options of taking her to the vet and the possibility and likelihood of her needing surgery, or some form of kittychemo but felt for a cat of her age, it would be hard for her to undergo surgery and we didn't want to put her through any sort of chemo.  At the very end of december we noticed the lump was gone! The foul smell of her breath is now present at all times, if her mouth is open or not. The brownish liquid is on her chin and parts of her chest suggesting the lump may have "popped," we are not sure as my friend has not found any mess in the house where the "popping" might have occurred. She is no longer hiding, but is still picky about her wet food. She is much more social and talkative and does not seem to be in any pain although there is a small "crater" where the lump use to be, but the area is not infected and the cat seems happy and back to her normal self. 

We are curious as to what happened to her cat, how a lump that was hard and seemed solid could be gone or possibly "pop." Any idea on what happened, what caused it, and tips on how to care for the "crater" on her chin or how to reduce the foul smell would be very appreciated. Thank you.

Here are before, during and after pictures (the last one is pretty gross, we think it was taken close to the time it "popped" and/or after she drank water)

Before:


This is while the lump was still growing, almost full sized lump.


the next picture is gross, I apologize, it is not meant to be offensive

I can't give too much insight, but that poor cat! Whatever is/was going on must have hurt! It probably would have (in retrospect) been a good idea to take her to the vet when the lump was growing. Lumps don't always mean cancer... I'm wondering if it was maybe an abscess? Sometimes people get abscessed teeth and have a huge lump swell on their jaw/face. Abscesses, if not taken care of, can "pop" and drain of their fluid. The reason she didn't want dry food anymore was because it hurt to chew the kibble (not sure if it was her teeth hurting or because the lump made it uncomfortable).

If I were you I'd advise your friend to take her cat to the vet and get her teeth checked. It's probably a good idea to make sure that what just happened isn't gonna happen again or isn't still happening.

Hi.  I just read your post about your friend's kitty.  This looks pretty much like what my cat, Larry, had about a month ago.  Don't know why it happened.  Didn't see any kind of wound or anything under his chin.  It started out just like yours, a little lump and then just kept getting bigger. His developed within a few days though.  I had just called the vet to make an appointment and while I was on the phone I noticed that he had scratched it and opened it up.  It smelled pretty bad and drained pus and a little blood.  It was thick and gooey, just like your friend's kitty looks.  I actually followed him around and dabbed it with a cloth because it was getting everywhere.  I also expressed it as much as I could without hurting him and it stopped draining real bad after a few minutes.  It oozed for several hours and I put a makeshift bandage on it.  After that it started healing up pretty quickly so I cancelled my vet appointment. I guess I'm rambling on too much, but to make a long story short the vet's office said it was probably an abscess.  About a week later it started swelling up again, the exact same way. I called to make another appointment and the same thing happened.  It burst again that same day and I did the same things and it started to heal.  But I did get some antibiotic from the vet and gave it for 10 days.  It has healed up nicely and no problem since then.  His breath was bad too while this was happening and is now back to normal.  So, I think that is what your kitty has, only it seems to have gone on a lot longer.  My Larry never quit eating and seemed to feel fine during all this.  I hope this helps.