Worried about cat with mammary gland mass

I took my long haired 11 year old female to the vet last Thursday because she wasn't eating much and wasn't herself and we realized she didn't feel good.  I also pointed out a lump on her lower stomach that we had noticed just the night before.  I really thought it was a mat.  The substitute vet (our regular vet is on vacation) said the lump was a mammary gland mass and that they are almost always cancerous in cats.  She did a blood panel and the only thing she found wrong was a low white blood cell count, which she attributed not to cancer, but to fleas.  She gave my cat, Sooty, an antibiotic shot, saying we needed to fix the low blood cell thing first, but to call for an appointment in two weeks to start working on the mass.  Friends I have who are knowledgeable in vet medicine said that makes sense.  I expected Sooty to perk up and feel better after the shot.  That has not happened and it has been five days.  I am having trouble getting her to eat and she is eating very little.  I have already made the two-week appointment, but I am worried.  Sometimes she nibbles at some food.  Yesterday morning she ate about a full serving of canned catfood, but little since.  When I spoke to the vet's office, they said if she stops eating, to call and they will get her in.  I have access to some appetite stimulants and will try those first today.  I have tried canned catfood, dry catfood, hamburger, lunch meat, cat treats (which she ate several of on Sunday, but won't touch since), tuna, scrambled egg, milk.  She isn't eating nothing, but it seems only enough to barely keep her alive.  I would like to know if anyone has any comments on this and if what the vet said makes sense?  Thanks.

I think the appetite stimulants are a great idea. I'm sure you know that it is critical for to eat every day or things can take a turn for the worse.

I would also pick up some Cat Nutri-Cal since she is not eating much. It is a high calorie nutritional supplement designed to give sick cats extra nutrients & calories in emergencies such as this.

Here it is on Amazon but I think they should have it at Petco/PetSmart too:

You wanted to know if what the Vet said made sense, but I'm not sure which part of what the Vet said you are questioning.

I must say that I've never heard of fleas being a cause of low white blood cells. but I'm not a VET.  Does Sooty still have fleas, or was she given a flea treatment?

I would say since she doesn't appear to feel any better now that it's almost a week later, you should bump up the appointment and start working on that mass (at least determine what it is before trying to decide what to do about it). 

Thanks for the info about the supplement.  Half an hour after I gave Sooty the appetite stimulant, she ate MORE than a serving of canned, then all the dry food in bowl.  This morning, she ate 1.5 servings of canned and a bit of dry.  So, it is definitely working.  I have enough to last a week.   I think for today and tomorrow, I will keep feeding her all the time, and then, as long as it is still working, cut her back to her regular  meals.  I dislike free feeding because, with 3 cats, you often don't know for sure who is eating.

The part I was the most concerned about was the vet wanting to wait two weeks.  I have heard that these mammary masses can spread really fast and that getting it removed quickly is key.  However, everyone also seems to agree that if she isn't healthy, she would not make it through the surgery.  So I guess it is a catch 22.

Sooty was due for her flea preventative the night before she went to the vet.  I didn't give it to her because she didn't feel good and I was unsure if I should.  After discussion with the vet, she did get her preventative, as well as a Capstar to kill the current fleas.  Yet she still doesn't feel good.  At least she is eating now.

Glad she is eating again. 

Unfortunately, there is no guarantee that the antibiotic is going to raise her white blood cells back up, because no one knows exactly what is causing them to be low.  The Vet said it might be because of the fleas.  There could be many reasons why they are low.   So...

BUT, not all mammary masses are so fast growing that two weeks will make that much of a difference.  When will your regular Vet be back?  If he's back now, I would call and ask him to review her last visit and see if you should come in earlier than 2 weeks, or wait or what.

I have an appointment with my own vet next week.  I was going to ask that Sooty be seen sooner, but I guess we have to try to get those white cells up.  I think as long as she is eating, I will try to wait.  I suspect her treatment, whatever it is, will not be cheap, so I don't want to waste money running her in if there is nothing they can do right now.  However, if it begins to seem like an emergency (not eating again), I will get her seen.  My husband and I do not think she had that many fleas that she would be anemic because of them, so we wonder if the low white cell count could be a symptom of the cancer??

I can't find anything definitive stating that low WBC is a symptom of cancer.  It COULD be a symptom of a viral infection, in which case an antibiotic is useless, but it COULD be a symptom of a bacterial infection, in which case that antibiotic might be very helpful.  It could ALSO be a sign of pancreatitis, which also greatly effects their appetite, and usually makes them feel pretty bad, so maybe that's it?  But with bloodwork, as my Vet recently pointed out to me, it's not just one number they look at, it's all of them put together.  That's why it takes years of medical school to get those little letters after their name (DVM)

Anemia usually causes low  Hematocrit and sometimes low RBC as far as I know.  Hematocrit for sure.