Hi, I am a Licensed Veterinary Technician and have worked in 2 different cat hospitals for well over 10 years.
I'm so sorry that Neffer has a mammary tumor : (
Unfortunately, as you probably know, these are quite aggressive tumors. I definitely understand your predicament about being unable to afford any chemo...and it is hard to say how much the chemo would help anyways in a situation such as this, so doing the best you can for her, as you are doing, is the most you can do.
I'm not sure what shot the vet gave, but if it was white and called Depo, then that shot would have been a steroid and will last for awhile, but I'm guessing it may have been Convenia, an antibiotic injection (which lasts for a week or so), since oral steroids were also prescribed. We wouldn't want to double up on steroids.
Is it Prednisolone? Or Prednisone? Cats can utilize Prednisolone better than regular Prednisone...so if you indeed have Prednisolone, I would go ahead and start it...if the injection already given was not a steroid. The Prednisolone can help keep Neffer's appetite and energy level up and will help decrease inflammation of the tumor. If it is Prednisone that you have, you may want to discuss with your vet about trying Prednisolone instead. Yes steroids can have some negative effects, but usually that is only if given long term. You would never want to take Neffer abruptly off of it once started though, you would have to wean her off.
A great natural healer is actually honey. Honey has antibacterial effects and great healing effects. Although it will not cure Neffer, it can help slow the progression of the ulceration of the tumor. Manuka honey specifically would be great to use on the ulcerated area. Here is a link:
Honey of course is messy, so you may need to attempt to wrap a light bandage around the area (if Neffer will let you : O) immediately after applying the honey for a bit to let it soak in and then remove it awhile after.
If the wound does seem to have a strong odor or you see pus, which can certainly happen as these tumors progress, then Neffer will need some antibiotics...
That is good that Neffer is eating well, but certainly if her appetite backs off, I would ask your vet for an appetite stimulant such as Periactin (Cyproheptadine) or Mirtazapine. Cats can get very sick if they go even a few days without eating well.
You do want to keep Neffer from licking the tumor area as much as possible because that could lead to infection faster. A soft e-collar would help keep her away from it and not inhibit her walking/eating much.
If she is leaving the area alone for the most part, then great and no need for a collar!
I hope all of this information has been helpful and I'm sure you will do the best you can at keeping Neffer comfortable for as long as possible.
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