Dog Cancer Blog

Well, it’s been 2 days since the lead-in entry on Vitamin C….which may (or may not) be a long time to wait  Anyway, here you go:

As I had indicated, it turns out that if one were to take vitamin C, at huge doses by mouth, the blood levels you get are puny. When you, or your dog, takes a pill, some gets absorbed into the body, but some passes out in the waste.

People who took 18 grams of the stuff (which equals gagging down 9-18 of those “horse pill” tablets) per day, only ended up with 220 micromol/L in their blood. That means a huge amount Vitamin C ends up literally going down the toilet.  

Those studies showing that cancer cells die when exposed to vitamin C  needed more than 1,000 micromol/L.  Since 220 is much less than 1000, the cancer cells were not dying.  

This is probably why the two clinical trials where people had to down 10 grams of vitamin C daily showed no benefit in surviving their cancers.

So the message seems clear…don’t bother with strait oral vitamin C (ascorbic acid) when you are trying to help your dog kill cancer cells.  In my opinion, bases on the evidence, you can’t get the levels you want for cancer cell death.

But there are other ways to get the stuff in the body.  What about injections?? Does that help?

Well, I could not find solid reports on the effects of intravenous vitamin C given to canine cancer patients.  Recall I want good, solid, science-based information…however, I did find some in the human literature.

A paper came out in 2006 that showed 3 human patients with tumors that would have been expected to have led to their demise opted for IV vitamin C at whopping doses.  Read the abstract here.

One had a form of lymphoma (lymphosarcoma), one a kidney tumor, and other was transitional cell cancer of the bladder.  All had signs of either local spread (into the surrounding areas) or distant spread (metastasis). Bad, bad stuff.   

The amazing thing is that in each of these three, the tumors went away.  Gone.  Nada. Zippo.  And that, my friends, is pretty astounding.  Granted, the lady with the kidney tumor (a chronic smoker) developed lung cancer 4 years later…but the information is pretty impressive regardless.

Does this mean everyone with a dog should go out and schedule IV vitamin C injections for their dogs? No. Especially not dogs with urinary stones like calcium oxalates, which likely can be worsened or theoretically even caused by the injections.  

But, it does mean that in certain circumstances, it should be considered.  Vitamin C IV injections appear fairly safe overall, and people are starting to pay attention to Vitamin C IV injections in cancer therapy…check it out.  For the vets out there, the protocols are here too.

Note that it is, at this point, probably unwise to give these doses of IV vitamin C in conjunction with chemotherapy until the issue of whether it helps or hinders chemo is clarified.  I would also avoid IV vit C at these doses if your dog is receiving radiation therapy.

Best to all,

Dr Dressler

Many have heard of the Nobel Prize winner Linus Pauling.  After winning the prize in chemistry in 1954, he went off on this tangent and decided to be the major proponent of vitamin C for health.

Lots of people became pretty excited, and decided to see if Vitamin C did anything to cancer cells in the lab.  In test tube studies, they found it sure did, see for yourself.  Melanoma cells, leukemia cells, neuroblastoma cells, carcinoma cells, fibrosarcoma cells…you get the idea.  Sure enough, it seemed Linus was on to something.

And Vitamin C did not kill these nasties by being an antioxidant.  No.  It actually had pro-oxidant effects, and increased the free radicals within the cancer cells to make them die.  See the blog on ozone for more about oxidation.

Anyway, among Mr. Pauling’s ideas was to take massive oral doses to get high blood levels so the vitamin C would do what it did in a test tube. Unfortunately for Linus, there was a flaw in his thinking.

You don’t get good blood levels of Vitamin C when you take it by mouth, and neither does your dog.  Turns out the body keeps the Vitamin C in a low range when given as a tablet.  And the range is too low.

Two published clinical trials found that vitamin C did not do anything for cancer patients. Things did not look good for Linus.

But it turns out that there is hope.  There are ways to use the cancer-killing effect of vitamin C for dogs with cancer.  And it turns out that these ways might really work.  Stay tuned for more!!

Best to all,

Dr Dressler

Ozone therapy is one of those things that people ask about sometimes.  Kind of an odd bird, ozone. What’s the deal with ozone therapy and dog cancer?

First of all, what is ozone anyway? Ozone is a gas that can be administered after it is dissolved in liquid, most commonly either IV or as an enema.  It is a powerful oxidant.

In cancer, at least two points about oxidation are important.  First, oxidation is the process that creates harmful free radicals (reactive oxygen and nitrogen) when the cell cannot eliminate them.  Excess free radicals hurts cells (damages the DNA, lipid, protein and more).

Second, the body has ways of combating free radicals naturally (dietary antioxidants, enzymes, pH buffers and more). When the body takes in an oxidant like ozone, the body will crank up it’s natural defenses against the damage caused by the oxidant.

Cancer cells have a tendency to produce lots of free radicals normally.  That’s actually a common theme in different  cancer types. Their defenses against free radical accumulation are low.  Thus, they are running on high gear, producing a lot of free radicals, but are living dangerously since they can barely neutralize their own free radical production.

This is where ozone comes in.  There is some evidence that it kills cancer cells in the test tube (see article), which is nice, but lots of things do that. Ozone increases the free radical production in the cancer cells, and these free radicals are toxic to the cancer cell.

The problem is this:  often something will kill a cancer cell in the lab but not in the body.  A cancer in a petri dish in not a cancer in a dog.

Unfortunately, there was no survival advantage when ozone was actually studied in cancer patients, as you can see. But it did seem to help with side effects from chemo and made the patients feel a bit better.  The reason why this occurred seems to be that the ozone therapy boosted the body’s natural antioxidant defense systems.  This is kind of like an immunization…a little of the bad stuff in the body boosts its defense.

A kind of neat fact is that ozone, dissolved as a liquid, does kill germs very effectively when applied directly to them.  Inhaled ozone is toxic to the surface of the lungs.

What’s the take home message? Basically,  I’m not excited about it for dogs with cancer.  The pro-oxidant effects do not seem to kill tumors in the body, and these effects initially may not be all that healthy for the body (prior to when the body recovers with it’s  own antioxidant surge).  Plus, there’s cost and availability issues.

Best to all,

Dr Dressler

Sound familiar? Did this happen to anyone out there?

Removal of all the cancer cells from the body during surgery is pretty important.  How can we tell?

The most important thing to do is get that biopsy report.  Some don’t want the extra cost.  “Just get it out” is a line I have heard from time to time. However, the report from the path lab can be absolutely critical.

Why does it matter?  Well, there are a couple of reasons.  First, the pathologist can evaluate the borders of the tissue I, or your vet/oncologist, submit after removal.  This is called comprehensive margin evaluation.

This evaluation tells us if there are cancer cells still left in the dog or not, around the surgery site anyway.  If there are cancer cells at the border of what gets turned in to the lab, there are probably some left in the dog.

So, if you get the path report back and there are cancer cells at the edge of the submitted specimen, it would be wise to go back in and remove more tissue. Yes, I am talking about a second surgery.

Some cancer types spread out around where the lump actually is resting.  So the dog will have cancer cells around the tumor that you can’t see with the naked eye. Some examples are osteosarcoma, some mast cell tumors, squamous cell carcinoma, fibrosarcoma, hemangiopericytoma (nerve sheath tumor), some mammary cancers (inflammatory carcinomas especially), hemangiosarcoma, malignant melanoma, and more.

In these cases, sometimes a wide excision (removing more than what “looks like” the cancer at the time of surgery is the way to go.  A fine needle aspirate or small biopsy before surgery can actually save cost in the end, by ascertaining whether a wide excision is needed before surgical removal.

Best to all,

Dr Dressler

I get a lot of inquiries that relate to whether a cancer is gone after it is removed, or what will be the outcome.

Sometimes these are tough to answer, and the reason is micrometastasis.

Micrometastsis occurs when a cancer spreads from a site, but the spread is not detectable by the usual means available.  Only a few cells take off, traveling perhaps in the circulation to set up shop elsewhere in the dog’s body. So few cells spread, that they are undetectable.

So you have someone like me take the tumor out, for example, and the borders are examined by a pathologist to see if the margins are “clean” (no cancer cells at the edge, they are all located near the center of the removed piece, suggesting complete removal).  Your path report says “complete excision” (complete removal).

Say though, that you are faced with the diagnosis of a malignant melanoma, a Grade 3 mast cell tumor, an osteosarcoma, an advanced squamous cell carcinoma,  a large hemangiosarcoma, or some other kind of canine cancer with a known tendency to spread.

Suppose your vet or oncologist was very thorough and did all that could be done to see whether there was evidence of spread, and all the tests were negative.  But your vet or oncologist is still pessimistic.  Why?

Micrometastasis.  The cancer did spread, but only a few cells.  These can sneak up on us later, turning up as cancers that were not there at the time we checked, but were there later.

This is why we are sometimes talking about steps beyond surgery when there is no evidence the cancer has spread. We want to make sure we are addressing the known tendency of these cancers to take off, even when the tests looking for spread are negative.

Best to all,

Dr D