Specialist Sarcoma in guinea pigs - advice needed whether to treat or not

[RosieMaia]

Hi there,

One of my piggies, 2.5-year-old Alice was diagnosed with mandibular sarcoma. This tumor first appeared in the summer, when it was judged on ultrasound to be most likely benign and we were advised to keep an eye on it. At the time, we decided against biopsy, as occasionally disturbing the tumor could inadvertently cause proliferation of malignant cells and the eye examination showed it to be innocuous. We were wrong.

I noticed things are likely not as they should when she started developing small lumps and bumps all over - she currently has around 10 on her body all over, including her armpits, which are likely enlarged lymph nodes. We did fine needle biopsy yesterday. The result was sarcoma - liposarcoma, unless I misunderstood our vet. She biopsied two of the lumps, the original one on the mandibula and one other, and curiously enough, the other one was inconclusive, i.e. might have been normal, healthy fat tissue.

We now have a decision to make. Operate and remove the (bigger) lumps, which our vet is confident she can easily do, hoping to achieve remission or at least some extension of life, or do nothing. The lumps are in no way interfering with her current quality of life, she's active, happy, healthy, inquisitive, pop-corning self. The stress of surgery could potentially change that for the worse, could cause her immune system to crash and change everything for the worse. At the same time, if the mandibular sarcoma, which is now the size of a small walnut, grows further, it may cause problems with swallowing and breathing and it may become more difficult to remove, if it grows near the carotid artery.

Our vets, who are exotics and whom I trust, recommend the surgery. The only reason I have doubts is that I see her popcorn... I could be robbing her of what is her last happy days, as no one can say that the surgery will ultimately have any benefit. Sarcomas in pigs are so under-researched that we just don't know.

What would you do if you were in my shoes? Would you risk a surgery, which may be without clear benefit? Or would you do nothing and wait?

 

[Bill & Ted]

Aw, I’m so sorry for your little piggies diagnosis, it’s a difficult one.
My piggie Bill had an operation earlier this month to remove two small mammary tumours just under one of his nipples. Our vet who is nearly 400 miles from where we live said they where likely to be aggressive mammary tumours and should be removed while they are small. If they are left to grow big then sometimes they attach to organs/blood vessels and become impossible to fully remove. There is also the big possibility of them spreading. We had the operation done straight away that day. I had only noticed a tiny lump about a week earlier and didn’t think it was anything with him being a Male piggie, but the vet said that it’s far worse than if he had been a female as he doesn’t have the hormones to slow and keep the tumour in check apparently.
Good luck whatever you decide, it is so difficult, because as you say, they are happy and well and you don want to see them having to go through operations x
Bill sailed through his operation and is very well

 

[Wiebke]

@Abi_nurse @furryfriends (TEAS)

 

[Abi_nurse]

Sarcoma is such a broad term. It is not unusual for sometimes the fine needle biopsy to be inconclusive, and sadly doesn’t mean anything either way. And the answer to your question is also very difficult one. I would say that at her age more malignancy is less likely. Recently seen a pig we took a lump off because it was suspect but after sending to the lab was not. On one side we felt bad for spending the owners money and putting the pig through surgery but on the other side we may have removed a horrible tumour. The pig recovered very well and was not worse for wear which is why I mention her age.

Again, not a right or wrong answer in this one. Sorry I cannot be of more help for you here.

x

 

[CuddlePigMum]

Just a thought - I'm a cancer researcher and although there's not much data in guinea pigs about liposarcoma, in humans the spread of liposarcomas to regional lymph nodes is pretty rare. This is mainly down to the tissue that the sarcoma identifies with not being able to metastasize or travel to the lymph nodes, in this case fat cells. Since this is a pretty basic tissue type survival principle it most likely applies to rodents as well. The enlarged lymph nodes could be an immune reaction to the tumour, just like when humans get cancer or a bad flu our lymph glands swell, mine do it so badly in my collar bone area that you can see them!

It's a difficult decision to make, at the end of the day the tumour is not going to go away on its own, that is a certainty, and it will only keep growing. It's hard to make a judgement on her immune system, and so much piggie medicine and prognosis is guess work anyway.

It's obvious you love Alice very much and any decision you make will be with her best interests at heart. I'd ask myself how much I'd regret it and think 'what if?' if I chose not to have the surgery and she only had a little time left but she was happy.