Since the procedure was first used successfully in 1986, Bone
Marrow Transplants (BMTs) have become one of the most promising medical treatments for a number of serious illnesses,
including the treatment of certain types of cancer. But did you know that BMTs are now also saving the lives of canine companions
diagnosed with cancer?
Although bone marrow transplants (BMT) have only recently become available as an accepted treatment
for dogs, they actually started being performed in a research setting about 30 years ago. Because of the amazing similarities
between dogs and humans when it comes to cancer, all of the current human transplant protocols were actually developed using
dog subjects. In fact, 95% of transplant procedures performed on humans were developed using dogs first. So, it
was only a matter of time until this groundbreaking procedure made it full-circle back to the species that originally helped
Bone Marrow Transplant
Basics Bone marrow is the soft, fatty tissue inside bones. This marrow contains stem cells, which are
the immature cells that give rise to all blood cells. During the bone marrow transplant process, the patient receives
high doses of chemotherapy and radiation to kill all existing cancer cells, and then receives an infusion of healthy stem
cells so their body can rebuild its blood supply with new, cancer-free cells. The BMT process allows patients to receive
much higher doses of chemotherapy and radiation than their body would be able to tolerate otherwise, which increases the likelihood
of a cure.
To qualify for a BMT at North Carolina State University,
dogs can be diagnosed with either B-cell or T-cell lymphoma, but they must weigh at least 10 kg and be in clinical remission.
However, that still doesn’t make a dog a good candidate. For dogs who have serious co-existing conditions or co-morbidities
such as Cushing’s Disease, kidney or heart disease, the BMT process would likely put undue stress on their system, creating
an unacceptably high risk for them.
How the Transplant Process Works To induce a clinical
remission, dogs must first go through chemotherapy. In most cases, the 25-week Madison Wisconsin chemotherapy protocol will
be used, which includes Prednisone and a rotating series of other cancer drugs including Vincristine, Adriamycin and Cytoxan.
If all goes well, dogs undergoing chemotherapy will go into clinical remission within the first few weeks of treatment and
will remain in remission throughout the 6 month protocol.
dog finishes chemotherapy, it’s time to begin preparing for the BMT. Similar to the treatment that most human
patients with B-cell lymphoma receive, canine BMT’s involve an “autologous”, or “self” transplant,
meaning that a separate donor is not needed. Instead, the stem cells are taken directly from the patient being treated.
To facilitate this process, the dog will first receive very high dose chemotherapy about 10 days before the BMT, to destroy
as many remaining cancer cells in the body as possible. They will then receive a drug called Neupogen, which drives
the stem cells from the bone marrow into the peripheral blood where they can be harvested by a special piece of equipment
called a leukaphoresis machine.
The harvesting procedure
itself takes several hours and is done under general anesthesia, as all of the dog’s blood is run through the leukaphoresis
machine. After this process, the dog undergoes total body radiation, with the goal of killing any remaining cancer cells in
the body. After all of this, the bone marrow transplant is officially ready to happen. Using a tube called a jugular
catheter, the harvested stem cells are reintroduced into the dog’s bloodstream in a process similar to receiving a blood
transfusion. Miraculously, these stem cells automatically know how to find their way back to the bone marrow and immediately
begin their important work of rebuilding healthy blood cells.
typically remain in the hospital for two weeks following the procedure to recover, and blood samples are drawn and checked
regularly to confirm if the transplant is working. Blood transfusions are often necessary when blood platelets drop too low,
but once the dog’s platelets return to a healthy range, the transplant is considered a success and the dog is ready
to return home.
When the patient returns home following the BMT,
they are on zero medications, and officially cancer-free. But, that doesn’t mean the recovery process is complete.
Lingering effects from the chemotherapy and total body radiation include GI disturbances and significant hair loss.
The most pervasive after-effect of treatment however is tiredness, which can last for up to 1-2 months.
Clinical Results Since bone marrow transplants
are so new to veterinary medicine, long term clinical results are not yet available, which can make it difficult to speak
authoritatively about cure rates and average survival times. However, for humans, the procedure results in a 50-60%
cure rate in those with B-cell lymphoma, and if history is any indicator, dogs could potentially enjoy a similar outcome as
they so often mirror humans when it comes to cancer treatments. In the meantime, veterinary professionals and pet guardians
alike can only marvel at the success they have seen so far in using this procedure with dogs. But, as with humans, cure
is not guaranteed, and some dogs will relapse. However, if the dog does not relapse within 3 ½ months of the
BMT procedure, they will most likely be “cured” or very long-term survivors.
So What’s the Hitch? So, if such a highly effective
treatment exists and could potentially save the lives of thousands of dogs each year, why aren’t bone marrow transplants
becoming a standard treatment protocol for dogs with lymphoma? The primary reason is that there are few medical facilities
capable of offering this treatment option because they lack both the equipment and expertise. North Carolina State University’s
Veterinary Teaching Hospital is currently the only academic facility in the country performing BMT’s in a clinical setting
with staff who have extensive experience using this technique. NCSU’s Dr. Suter is the hands-down expert in performing
BMT’s on dogs, and the university has also hired the nation’s first BMT Fellow who will be working with Dr. Suter
for the next year to learn all about canine BMT, so they can begin transplanting even more dogs. Although there
are a few private practices across the country that say they can perform the procedure, the fact is that they do not have
the expertise or experience required to really make it a viable option for pet guardians. As more cases are documented
however, and as additional vets gain experience using this technique and more facilities add leukophoresis machines to their
cancer treatment centers, the hope is that BMT’s will become much more widely available in the next 3-5 years.
The second, and perhaps more obvious, reason that more pet guardians are not pursuing
bone marrow transplants for their canine family members is the high cost of this procedure, which averages about $14,500.
If this sounds astronomical, it’s really quite a bargain. For humans, a BMT can require up to 6 months of hospitalization
and care, costing between $100,000 and $250,000 dollars. While the goal is to eventually bring BMT’s for dogs
into the $10,000 range, this is still a lot of money for most families, even if pet insurance covers a portion of the expenses.
How to Learn More Save-An-Angel is a non-profit organization dedicated to helping dogs with lymphoma – especially those who are candidates for a bone
marrow transplant. Save-An-Angel was founded by Kristie and Johnny Sullens in honor of their little girl Angel, who
received a canine BMT at NCSU in 2010 and is now proud to be called a cancer survivor. Save-An-Angel provides information,
guidance and support throughout the BMT process, and will also help pet owners identify ways to help fund the procedure for
their canine kids. Georgia's Legacy is proud to be a partner with Save-An-Angel to promote canine cancer awareness
and increased access to Bone Marrow Transplants for dogs with lymphoma.
learn more about Save-An-Angel and to find out how you can get involved, visit www.save-an-angel.org or find them on Facebook!
CLICK HERE to read more about Angel’s journey to cure in this special report on Canine Lymphoma that the founder of Georgia’s
Legacy wrote for K9 Magazine.
This website is not intended to replace the advice of a veterinary professional, and is for
informational purposes only. Please seek the advice of your veterinarian or a veterinary specialist before giving
your dog any supplements or pursuing any alternative cancer therapies.