Sadie... again.

Today, our dalmation Sadie is going to the vet. A few months back, we had her in and had some tumors removed from her head and neck. We didn't biopsy them because even if she *did* have cancer we couldn't afford to pay for doggy cancer treatment. The surgery was costly just to remove them. Anyway. She's now really losing a lot of weight and I wish that we would have done the biopsy so I'd know whether this is cancer making her lose weight.
She's going to the vet because I need to know whether she needs comfort while she gets sicker.... or if (fingers crossed) it's a simple fix like a parasite that can be cured with a pill. She's really old, 12 years, so I expect her to act elderly.... but this weight loss scares me.
I hope she's ok.