Last updated on Tuesday, 26 October, 2010 22:17

How can one treat it

An overview of the several treatment options available

This is the part of the site most people will probably want to see. I'll try and keep this section sourced and updated so you can discuss the therapeutical options with your vet, which is and will definitely be your greatest support. If you can't trust your vet, find one you can trust because, however things turn out, you won't want to have any regrets.

Now, as you can imagine, there are many conventional and not-so-conventional treatments for feline fibrosarcoma at your disposal. The fact that these exist doesn't mean they are cures, and some are far more commonly applied than others, either for practical or cost issues. I'll separate them and give a small overview of what they entail, so you can have an idea of what to expect, but not all of these may be available to most people, and some are probably too experimental to be recommended by your vet. Knowledge is power, though, so I hope this helps.


Surgical excision is by far the most common option used for addressing a fibrosarcoma. It is well documented, relatively easy and quick to perform, and relatively inexpensive. Unfortunately, is has a very low rate of success as fibrosarcomas are invasive tumors and relapse often, forcing the excision to have very wide safety margins (at least an inch, in all directions, as a rule of thumb) to have any hope of succeeding. This requires a vet that knows exactly how to proceed, and of course, an early diagnosis. The smaller the tumor is, less tissue needs to be removed during surgery, making for a faster recovery.

As always, there are those predictable complications for every surgical intervention, mostly related with anaesthesia, infections and the actual recovery capability of each patient, but these are minimal nowadays, and many cats have been operated on multiple times to remove relapsing fibrosarcoma tumors without any surgery derived complications.


A fairly common treatment for cancer in humans that, where available, is often used as a preoperative or postoperative therapy in feline fibrosarcomas. It isn't used by itself unless the tumor is non resectable, and only for palliative reasons. It is a more common complement to surgery where it can increase the survivability and relapse free time lapse after excision.

As limitation, it is only really useful for tumors with a high mitotic rate, and only when applied immediately before and after a first excision, not after relapses, and on a well localized tumor, preferably small ones.


Probably the most common option for the treatment of cancer in humans, it finds some success in the management of feline fibrosarcoma. It is limited however by the fact most sarcomas replicate slowly, so the effectiveness of chemotherapy is reduced, and side effects are enhanced, due to the dosages needed. However, I may be oversimplifying, as there have been many new studies regarding the possible avenues for chemical management of fibrosarcomas, ranging from plant and fungus extracts all the way to monoclonal drugs. I'll try to point some out as well.

The most commonly used chemotherapy drug used is called Doxorubicin. Is is actually an Antibiotic that works by intercalating DNA (it basically stops biosynthesis by interfering with gene transcription). Unfortunately, it has a taxing effect on the body, specially in the heart and kidneys. It is sometimes given along with Cyclophosphamide, a helper drug that slows down cell growth.

Like all chemotherapies, is causes a tremendous amount of damage to the organism, because it is designed to kill some of it (cancer, of course), and at this time, while it does increase the time it takes for the tumor to relapse, it is still not a cure for feline fibrosarcoma. The next topic addresses the side effects this therapy presents.


A personal favorite of mine. It appears to be a very localized from of distributing chemotherapy drugs directly through the skin, resulting in a greatly enhanced effectiveness of the drugs and the severe reduction or even elimination of systemic side effects. Based on the principle of electroporation (using electric fields to increase cell permeability) it has achieved remarkable results regarding to feline fibrosarcomas in trials and testimonies. It is also used for the treatment of melanomas in humans. Unfortunately, it is still rare, and while it is much more cost effective than other therapies, the machine used to perform electrochemotherapy requires a substantial investment by the veterinary practices (around 50000€) so only large practices have the ability to provide it. It is my hope that it becomes the standard treatment as it presents very good survivability and quality of life results for a residual cost.

It consists simply in injecting a chemotherapy drug like Cisplatin or Bleomycin directly into the tumor, and them imposing a very strong electric field around the tumor so the drugs are forced into the cells, as the cell walls become "more porous" (in truth, all cells haves "pores" so things can get in and out of them, and the electricity just makes these holes bigger). As a result, it takes a much smaller quantity of drugs, and these only affect the tumors, so it does not present any systemic side effects. There is a video of such an intervention you should see, though it's on a person, not a cat. It is here, and it isn't really gory at all. It is made by the University of Ljubljana, one of the first to study its application on feline fibrosarcomas. I'll put up some more interesting links regarding this therapy at the bottom.


Once the mainstay of cancer therapy in cats, along with surgery, it has lost some of its appeal in recent times, as it is a very non specific treatment that ended up not being effective at curing or just treating tumors, but also because of the systemic impact it has on the patients.

The most common immunotherapy agent used is Interferon-Ω (usually marketed as Virbagen®Omega). It is given intratumorally before surgery and intradermally after surgery at the excision site. It has had some success in staving off relapses but it causes weight loss and overall depression, though it is usually bearable. Interferon does exactly what the name says, it interferes with cell functioning, in particular, protein synthesis. As a result, viruses and tumors are most affected, but it ends up affecting the entire organism to a lesser extent.

Other Approaches

Here I'll go over some of the other less talked about approaches. Some conventional, some not so. A few of these are destined to just treat fibrosarcomas in very specific circumstances, others hold the promise of being universally curative but are still not fully understood (to go along with our lack of understanding of cancer). I'll also tell you which I tried with my sister as conventional treatment failed her.

First off, I considered/researched these therapies because they are side effect free (or almost so), and because they are easily accessible and/or easy to administer.

For a while now, humans have know that Silver has anti-bacterial properties. Silverware was upon a time a must have for upper class families, and there was an old tradition of dropping a silver coin in a jug of milk to keep it from spoiling. It is now seen in dressings for hard to heal wounds and there are some evidences that silver (and gold) nanoparticles may provide an excellent course of treatment for cancer. In "The Body Electric", Dr. Becker describes how he used silver iontophoresis to regenerate non-healing bone fractures, and he details how the same method can be used to halt or induce cellular mitosis through manipulation of cellular regression and differentiation. Now, that is a bit too fancy (though I wonder why it isn't being actively researched) so I tried the more common form of therapeutic silver: colloidal silver. It's basically pure water with finely dissolved silver in it, approximating the supposed effect of silver nanoparticles. There is that condition called "Argyria" where people turn silvery-blue color. However, this happens because the silver stains the skin, which can only happen if your body can't eliminate it, so it rarely happens. And besides, it doesn't pose any other health risks (though the fact it appears may indicate reduced renal function). I gave Nina a regimen of 125ml of day of colloidal silver, and, if it didn't cure her, she loved drinking it, snubbing regular water for it. Maybe it was a placebo for her, but while she was on that regimen, the tumor did not develop visibly.

Another thing that I tried was giving her a bit of wine. It's not what you think. Actually, wine is not important, what's important is the melatonin it contains. One of the reasons tumors appear, is because the p53 gene is malfunctioning. The p53 gene is one of the tumor suppressor genes that makes a cell self-destruct it it turns cancerous. It has been found that this gene is damaged or deactivated on several fibrosarcomas (most tumors in general), and melatonin is thought to increase the p53 gene expression. Based upon this info, I would clean the ulcer the tumor had formed and gently moisten her skin with a wine soaked cotton-ball. It definitely didn't seem to bother her and it seems she even enjoyed it. Or maybe she just enjoyed the attention (not like she didn't get a lot of that). I have experienced the good effects of wine myself, on a 2nd degree burn I once had. It healed over quickly and seamlessly. I'm surprised it isn't used on burn victims.

At last, I also gave her some vitamin C (in the form of calcium ascorbate - should have been magnesium ascorbate instead), in order to protect her kidneys and help her overall wellbeing.

There are plenty of other and new therapies available. A really interesting one was using lipopolysaccharides as a therapy. These molecules induce fever, and it has been know for some time now that fever is highly negatively correlated with complete cancer remissions in humans. There are plenty more choices though. Some are a new spin on old school approaches such as Acemannan, which is a drug extracted from Aloe Vera, of all things. Others are state-of-the-art combined immune approaches like the apSTAR (Autologous patient specific tumor antigen response, as Wikipedia puts it), which apparently works by teaching the body to fight off cancer cells as if they were any other intruders. I'll try to add to this overall list and if you have anything to add, let me know through the "Contact Webmaster" link at the bottom-left of the page.

Here are some more links:

Vaccine-associated fibrosarcoma in a cat

PetCancerVet - Electrochemotherapy

Anti-proliferative activity of silver nanoparticles

Effect of Anodally Generated Silver Ions on Fibrosarcoma Cells

The Treatment of Feline Fibrosarcoma with Lipopolysaccharide and Cyclophosphamide

Felipedia - Interferon - Case Study (.PDF)

The Effect of Melatonin on the Proliferation and Apoptosis of Fibroblast from Hypertrophic Scar