A promise to Kali

so a few months ago Kali had to have 4 breasts removed due to lumps. I never had them tested for cancer but the Dr. said from his experience they did not look to be cancer. she had 2 removed first then a few months after that the other 2. her 2nd surgery was HELL on her & me!!! she was in the worst pain I have ever seen her in she was doped up on lots of pain meds but all she did was cry. I was in agony over her pain. All I did was pray for God to give me all her pain. it took several weeks for her to be well enough to go off the pain meds and several months to be back to her old self. I would stay up for hrs just holding her and crying. It was at this time I promised her NO more surgery's this was it.
Kali had alot of scar tissue especially in one area it was so bad I was worried her lump was back so I took her back to the vets to be checked and he assured me it was just scar tissue. now its been a couple more months and her "scar tissue" is bigger about the size of a base ball and hard as a rock. The other 3 areas look great. so now I have yet another appt with the vet to see if this is still scar tissue.
What do I do if its bad? do I break my promise to her and do another surgery? How many times do I put her through this?Am I cruel if I do nothing? she seems ok other then the lump still eating and being her normal lazy self. Im trying to be optimistic but I already know the Dr, will want to do another surgery. I pd over a thousand bucks for this last one where will I get the $ for another?