I took Roxy to see an Oncologist yesterday. She was recently diagnosed w/ a fibrosarcoma they believed was brought on by a series of vaccines she received in 2001 at the Humane Society where I adopted her (it's called feline vaccine-associated sarcoma or VAS). The oncologist obviously knew his stuff and was very kind on top of everything. I left the hospital and cried the whole way home thinking I'm a bad person for considering the financial impact b/c he obviously recommended radiation therapy post-surgery (we had the tumor removed on 6/25)... but it's going to cost $5K - $6K. I felt so hopeless.
I ended up calling him back a few hours later w/ a couple more questions about statistics and prognosis, and the confession that the financial impact was probably going to be too great to bear. I was grateful that he took the time to ensure I was clear on worst/best case scenarios and average statistics, and especially when he sanctioned the path I'm most likely going to take.
Here's the bottom line:
Unfortunately, my regular vet made a mistake in not sending the extra tissue from the surgery (I had a special surgeon do the surgery at my regular vet; $2400 on top of the $750 already spent on diagnostics) to the pathologist in order to determine whether or not there were clear margins on the tumor. Apparently, the surgeon took the tissue from her in two steps: the first was the majority of the tumor itself, which was huge, and the second step was to then go in and remove about 2 extra inches around the excision to ensure they got any stray cancer cells (this type of cancer is particularly aggressive and it branches out so there could be microscopic cancer cells still left behind). My vet only sent the tumor itself to the pathologist, not the extra tissue the surgeon took to ensure he got it all. On the tumor itself, there were not "clear margins," meaning there was not enough good tissue around it to indicate they got all the cancer. Since they didn't send the rest of the tissue, which could have indicated clear margins, we will never now know. This means, of course, that it's even harder for the oncologist to determine whether radiation is definitely needed or not. The only good news is that the surgeon does believe he got it all (but, of course, there are no guarantees).
In the absence of knowing for sure whether there were clear margins, and b/c the likelihood of the tumor growing back in the face of surgery alone is 50%, the oncologist is recommending radiation as the best possible thing to do to mitigate recurrence.
However... these are the facts:
Worst case scenario - the tumor was not completely removed and it comes back quickly, which is anywhere from 2 weeks to two months post-surgery.
Best case scenario - the tumor was completely removed and she's in the 50% percentile of no recurrence; she lives out the rest of her natural life.
Average scenario - the tumor was not completely removed and comes back w/in 6 - 9 months.
IF I DO RADIATION:
On average, I buy her 1.5 years, and possibly up to 4 years of disease-free life. But, of course, there are no guarantees; it could fail.
Based on just the statistics alone, I don't buy her that much more time on average. Plus, even though cats tolerate radiation way more than humans, and putting aside the cost, I would have to take her in every day except weekends for 19 sessions and she would have to go under anesthesia each time. She hates to just go see the regular vet annually!
Truth be told, if money were no object, I would probably do it; but the reality is that I don't have this money and am already in debt. So, given that it is still possible the surgeon got it all and she could be "cured" (best case scenario), I think I'm going to take my chances and go another route... which the doctor completely sanctioned (he even said that if he thought I was putting her life in great danger, he would tell me). That is, I am going to be hyper-vigilant about looking for any new lumps near the site. The good news is that these tumors usually grow back in the same place or in an area where the "branching finger cells" infiltrated close by. So, it should be easy to find if one does. He also recommended maybe even bringing her in to see my regular vet for a more professional evaluation of the same thing (which is only about $40) every two months or so. The other other good news is that this cancer does not often metastasize (only 20-25% do). If the tumor grows back, then I can re-consider radiation and another surgery (which is more successful than surgery before radiation, which we did)... or let her live out the rest of her days as comfortably as possible knowing that she's had a pretty good life at 11 - 12 years old, and being strong enough to make the tough decision to end her suffering at some point along that path if it comes back.