New Dog Cancer Cure: Targeted Chemo Hylaplat Gets Results

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New Dog Cancer Cure: Targeted Chemo Hylaplat Gets Results

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Photo Credit By cogdogblog 

A New Therapy for Dogs With Metastic Cancers Is Now Available And Getting Good Results

A new drug, HylaPlat, has produced high cure rates for many different forms of Canine Cancer. By way of targeting the cancer, and directly injecting it with Hylaplat chemotherapy, results have been dramatically improved locally, as well as systemically. So far the drug has proven highly effective on a variety of metastic cancers.  Trials are ongoing through veterinary practices, and your vet’s practice and your dog may be able to participate for free. Contact Information for canine cancer trial participation is located at the bottom of the article.

What is Hylaplat, The Injectable Chemotherapy?

The team at HylaPharm (a 2011 startup affiliated with the University of Kansas) blended Hyaluronan and Cisplatin to create HylaPlat.  The brain child of pharmaceutical chemist Laird Forrest Ph.D. and Daniel Aires, M.D., Director of dermatology at KU, Hylaplat is showing promise with canine cancers, and they hope to see it in human clinical trials as well in the future.

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Hyaluronan is a natural polymer found in the body throughout connective, epithelial and neural tissues. It contributes significantly to cell proliferation and migration, and may also be involved in the progression of some malignant tumors.

Discovered in 1845 and licensed for medical use in 1978, Cisplatin is a chemotherapy medication listed by the World Health Organization as one of the Essential Medications. Currently, it is used intravenously to treat a number of cancers, including testicular, breast, bladder, ovarian, cervical, lung, brain and esophageal cancers in humans. 

It works by binding to cancer cells and preventing DNA replication. However, it does have some serious side effects such as auditory, kidney and nerve damage as well as the nausea and vomiting often expected from chemotherapy treatments.

 

Utilizing a blend of Hyaluronan and Cisplatin, Hylaplat makes possible a non-destructive, local injection which “sticks” well to cancer cells, allowing for an efficient uptake of cisplatin into the tumor cells.

Localizing the treatment to the tumor site, allows for a lower, targeted dose to be administered, thereby minimizing some of the more threatening side effects to the kidneys, nerves and auditory organs.

Photo Credit Celsim Junior - Flickr

As explained by Dr. Ares, “Injecting it directly into the main cancer lesion results in a very high drug level compared to normal injections into the veins,” Aires said. “Furthermore, most cancer cells have a receptor on their surface that grabs onto hyaluronan. In general, more aggressive cancers and the hard-to-treat cancer stem cells have more of these receptors. This is another factor that can help target the drug to cancer cells.”

Additionally, with Hylaplat, the compound molecule itself is very small. Because the compound molecule of Hyaluronan and Cisplatin is only 20 nanometers in size, after doing its work in the tumor, HylaPlat drains easily into the lymph nodes, delivering a high dose of chemotherapy to any cancer cells that may be hiding there.

As a result, HylaPlat may have additional advantages for treating cancers that metastasize through the lymph nodes; a category that includes 85 percent of human cancers. Breast, ovarian, colon and lung cancer are included in this category of metastic cancers. Standard chemotherapy treatments, in use today, tend not to get into the lymph nodes at substantial therapeutic levels, resulting in a greater risk of relapse.

Use of Hylaplat to Treat Canine Cancer

Traditionally, researchers begin testing cancer treatment on laboratory animals by first inducing a laboratory derived cancer.  Unlike naturally occurring cancers, these tend to have homogenous cancer cells grown carefully under laboratory conditions.  They are not very hardy, unlike naturally occurring cancers, that tend to have diverse cells and are better at evading the body’s natural immune system. 

By using larger animals with systems more similar to that of the human anatomy, comparative oncology researchers can better understand how new drugs may affect human patients. Dogs with naturally occurring cancers are an ideal population for testing drugs on a diverse group of cancers. So far, HylaPlat has proven effective in animal models, and larger animal trials for submission to the Federal Drug Administration are currently under way.

The Initial Trial Results for Cancer in Large Breed Dogs

In the initial clinical trial, which started in 2012, seven large-breed dogs with small forms of oral cancer received a formulation of the Hylaplat chemotherapy. The dogs in this study were suffering with naturally occurring cancers.

Of those first seven dogs, the cancer in three patients disappeared, and two other dogs showed signs of partial remission or slowing of the disease. These promising results gave rise to a feature story on a local television news network. Hylapharm was suddenly flooded with requests from pet owners with dogs suffering from all forms of cancer that wanted in on the trial.

Faced with this tremendous demand and the potential for experimenting with all sizes of dogs and various metastic cancers, researchers lifted the restrictions on the size of the dogs and types of cancers being tested. Additionally, local veterinarians were trained to use the treatment for cancers all over the bodies of dogs, including muscle and bone tumors, melanomas, sarcomas and lymphoma.

Injection of Hylaplat is performed by first sedating the dog, then injecting the chemotherapy directly into the tumor. The original treatment protocol called for four injections over a period of several weeks, however, some dogs have responded after just one injection. In general, the dogs show little to no side-effects to the treatment, with them adapting to their normal routines shortly after treatment.

Better yet, at this time, it is a very affordable course of treatment, while traditional chemotherapy has been cost prohibitive for many pet owners. Currently, the owner need only pay for the sedation and administration of Hylaplat. Traditional courses of chemo can run into the thousands of dollars with side-effects that often cause owners to regret their decision to pursue it.

Getting a canine version of HylaPlat to market, however, appears to be on the fast track, which should come as a delight to pet owners and the drug's creators.

The Canine Cancer trial is still accepting patients. If you think your dog could be a candidate, please call 913-588-3840 or email jadams4@kumc.edu.

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How To Easily Determine Dog Age By His Teeth

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How To Easily Determine Dog Age By His Teeth

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If you’re wondering about a dog’s age, the condition of his teeth will give you a lot of information. The old expression, don’t look a gift horse in the mouth,is derived from the fact that horse’s teeth have distinctive wear patterns, that can help you determine his age fairly precisely for the first 7 years of his life and well beyond. Just as horses’ teeth provide strong evidence of their age, dog teeth have distinctive wear patterns that can help you to discern the age of your new family friend fairly accurately.

3 week old toothless puppy

How Many Teeth Do Dogs Have?

Puppies should eventually have 28 deciduous teeth, 12 incisors (the  small front teeth - 6 upper and 6 lower), 4 Canines (the fangs) and 12 premolars and molars. They are missing the first premolar and the last molars, that will eventually develop in the adult dog.

The incisors are located along the front row of teeth, between the canines. Incisors are used in grooming and nibbling activities. The canines are used for tearing in conjunction with the incisors and premolars. The premolars follow the canines on the sides of the jaw; the premolars and eventually the molars are used for heavy chewing.

Adult dogs should have 42 teeth: 12 incisors, 4 canines, 16 premolars and 10 molars (2 on each side of the upper jaw and 3 on each side of the lower jaw). For many breeds, full dentition is an issue, and they may develop fewer adult teeth. Missing premolars are more common, but dogs can fail to develop canines, incisors and molars. For many show dogs and especially in the working breeds, full dentition is a requirement. However, many toy breeds such as the Chinese Crested are notorious for missing teeth, and allowances are made depending on the degree of missing dentition.

How Long Do Puppy Teeth Last?

Understanding the sequence of development of puppy milk teeth can assist you in gauging a puppy’s age. Like most mammals, puppies are born without teeth, and their mothers are grateful for that!

• At around 3 weeks of age, the incisors begin to erupt.
• The incisors are followed by the canines at around 4-5 weeks. These new puppy teeth are very sharp and brittle, encouraging the mother to begin weaning her puppies.
• By 8 weeks the premolar #2 and molars numbers 3 and 4 have appeared.
• From 8-12 weeks there will be very little change in the puppy’s mouth.
• As the adult teeth form, the roots of the milk teeth should begin to reabsorb.

Eleven week old puppy incisors flanked by the canines.

Eleven week old puppy canine, premolars and molars.
Note the first premolar is missing.

At 12-13 weeks puppy teething begins. The new adult teeth should push out the rootless, deciduous milk teeth, although occasionally puppy teeth are retained. If the puppy teeth do not fall out on their own, they will need to be removed by a veterinarian to prevent them from affecting adult tooth placement and the dog’s bite.

• Starting around 12 weeks the incisors will begin to be shed and replaced with their adult counterparts.
• At 4 months the canines (the fangs) will begin to erupt.
• By 5 months, all of the adult incisors should be in place.
• The adult premolars and molars come in between 5 and 7 months of age, erupting from the front of the mouth with the premolars to the back with the final molars.
• By 8 months of age, a puppy should have all of his adult teeth.

5 Indicators of Dog Age By Wear On The Teeth

The condition of a dog’s teeth can be an excellent indicator of his age. However diet, oral care or lack thereof, as well as behavior can affect your ability to properly gauge a dog’s age.

Factors such a antibiotics taken while adult teeth are forming can affect tooth color from the start. Chewing on bones and other hard toys or surfaces or fence fighting can prematurely break teeth. Also a diet based exclusively on soft food can accelerate tartar build up and tooth decay. The following guidelines can give you a reasonably good estimate of the dog’s age given that he has enjoyed a normal diet that includes kibble.

At one year of age the dog’s teeth will be very white. The lower incisors will have ridges on top of them (the cusp) that resemble a fleur de lis design or that of a three leaf clover. (As time progresses, the pattern of the incisor teeth will begin to wear down).

Note the fleur de lis pattern on the lower teeth
 is clearly evident on the center incisors.

By 2 years old, the dog’s teeth will no longer be as bright white as they were at the start of his first year. Depending on diet and oral care, some yellowing and tartar buildup may have begun on the back molars.

Incisors of a two year old border collie; the fleur de lis pattern is still 
evident on the center incisors, although it is beginning to wear down.

From 3-5 years of age there will be yellowing on all teeth, tartar will begin to build up on the molars, and the front incisors will begin to show wear. The cusps of the lower front two incisors will begin to grind down and the fleur de lis pattern will begin to erode; by 5 years old half of the ridges of the cusps on the lower incisors will have worn away.

Incisors of a three year old border collie; 
center incisors are beginning to show wear.
   

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  Incisors of a 5 year old border collie; note that the 
  center two lower incisors are very worn down.

By seven years of age, the cusps of the lower incisors are worn level and those teeth are substantially short that they were when they erupted. Canines will begin to blunt as well. Without dental intervention, the tartar build up on the molars will appear orange or medium brown.

Incisors of a 7 year old border collie. Here all lower incisors 
are ground down from contact with the upper incisors. 

At eight years old and beyond, teeth may be broken or missing. Some older dogs (9+) may also experience buildup of gum tissue (Gingival Hyperplasia). In this instance the gums appear swollen above the canines, however it is just a build up of extra gum tissue.

Fooling the Experts With Good Canine Dental Care

While you can't avoid the wear and tear on incisors in a close scissor or level bite, you can affect the health of your dogs teeth and gums with good oral hygiene. Regular brushing with specially formulated canine enzymatic tooth paste can substantially reduce tartar and the yellowing associated with tartar buildup. Crunchy treats such as carrots, raw chicken thighs and chicken feet can massage gums and reduce plaque buildup as well, while fleece tug toys and nylabones can also promote oral health.

Raw Bones Versus Antlers: Raw beef shank bones and marrow bones are delicious for dogs to chew on, but they can easily crack and break teeth.  Naturally shed deer and elk antlers are equally delicious, and they are softer and more porous that marrow bones. The porous aspect of the antler also makes it a better plaque remover.  If your dog loves to chew, an antler will quickly remove most of the tartar on the molars and premolars. Choose the non-split variety for a longer lasting chew and a better value. The upper canines will likely still need scaling.

Elk Antlers make good canine dental care easy.

Buy It Now

If your dog still has plaque buildup after gnawing on a variety of dental toys and chews, your veterinarian can clean his teeth quickly and safely. Check with her to see if she will have any oral health care specials coming up, and plan to take Fido in for a cleaning. His newly rejuvenated pearly white teeth will thank you for it!

Dog Behavior: What's Behind the Guilty Dog Look?

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Dog Behavior: What's Behind the Guilty Dog Look?

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Did he do it?

Does this dog look guilty to you?

Is it a mistake to confer human emotions and motives on our dogs? Are dogs really more human than some of us are prepared to believe? 

Recently, dogs have become the new darlings of cognitive science, and research exploring the range of canine emotions and cognitive abilities is mounting at an exponential rate.

Among the many human characteristics attributed to dogs is the concept of guilt. It’s not unusual for a dog owner to state, “I knew he had done something; he had that ‘guilty look.’” We all know that doleful, guilty dog expression, but does it really demonstrate that dogs feel shame? If not, what’s behind it? Researchers at University Barnard College in New York set out to answer a few of these questions.

The Guilty Dog Experiement

In a study by Alexandra Horowitz, Assistant Professor from Barnard College, dogs were placed in a controlled environment where they and their owners were setup to make guilty dogs appear innocent and vice versa. Dogs were ordered by their owners to leave a tasty treat alone, then the owner left the room.

After the owners left the room some dogs were offered the forbidden treat by the researchers, which they ate, while others obediently awaited their master’s return. What the researchers told the owners about their pet’s behavior often did not correlate with the events that had transpired in their absence.

Owners who were told truthfully that their dog had disobeyed them by eating the treat, and who then scolded their dogs, received a guilty look from the dog. However, when researchers falsely stated that the dog had eaten the treat in their owner’s absence, the innocent dogs that were scolded for eating a treat they had not consumed, demonstrated the guiltiest look of all dogs in the experiment.

This suggests that the guilty look stems from a reaction to the scolding, and not to the dog’s true guilt or innocence. However, further research indicates there may be more to the guilty look that what we gather from this experiment at first blush. 

So what are the dogs really responding to; what do dogs think and feel with regard to their human caregivers?

The Dog Genius

According to Brian Hare co author of The Genius of Dogs: How Dogs are Smarter Than You Think, “The genius of dogs is that they use probably the most powerful tool on Earth to solve problems—humans. At one point in wolf evolution, a group of wolves decided to take advantage of humans, and they have been really successful because of it.”

By hitching themselves to humans, dogs have become one of the most successful species on the planet. Dogs domesticated themselves in a process where the most tolerant, attentive and least aggressive dogs did best with their new companions. In an 18,000 year process, the brain and sensitivities of the dog have been refined to better coexist with man. It seems that dogs have developed many of the coping skills that we observe in young human children.

Our Canine "Kids"

The Bassett Hound always wears
 a bit of a remorseful expression.

Many dog owners refer to their dogs as their “canine kids.” But are adult dogs really like human kids? Researchers Lisa Horn, Ludwig Huber, Friederike Range at The Clever Dog Lab sought to determine if dogs, like human children, display a “secure base effect.” Essentially the secure base effect in young children refers to an attachment bond where the child refers back to the caregiver for reassurance while exploring the world. The presence of the caregiver provides a sense of security, the secure base.

In human tests, children perform better on cognitive tests when their caregiver is present in the testing environment. The researchers for this canine experiment set up four conditions using a problem solving dog toy that dispenses treats as the model for the cognitive test. Dogs were left with the toy in one of four scenarios: alone without a human presence, with a stranger, and with their owner actively encouraging the dog to interact with the toy and finally, with their owner in an inattentive state.

Dogs left alone with the toy had minimal interaction with it. Dogs left with strangers interacted slightly more with the toy. And those with their owners present interacted statistically significantly more with the toy whether the owner was attentive to the game or not. This demonstrates a remarkable secure base effect with their caregiver; one that adult dogs retain throughout their lives, yet one which normal human children eventually out grow.

It appears that this parent/child bonding is mutual. Ocytocin is a neurotransmitter that is essential in the bonding process across all mammalian species. It is essential for the development of the parent/child bond as well as paring bond in mating processes.

In an experiment, pet owners were asked to complete a questionnaire that described the bond they felt with their dog. Afterwards they were asked to give a urine sample, and then to play with their dog for 30 minutes. Following their play session, they again provided a urine sample. The analysis of the before and after samples showed that those with strong bonds to their pets also had increased levels of oxytocin in their urine samples following the play session with their dog. The increased levels of ocytocin correlated with their level of attachment they reported experiencing with their pet. It appears we are biologically bonded with our dogs.

Working agility at a distance based on handler' body language.

Source: By Ron Armstrong from Helena, MT, USA (HMKC Spring 2007 Agility Trial) [CC-BY-2.0 (http://creativeco

Dogs Are More Like Us Than Other Primates Are

Research over the last 10 years is turning up some surprising facts about dogs. Their ability to follow a gesture or a human gaze is unparalleled among other species, including the chimpanzee. If we fix our attention on an object, by pointing or looking at it, the dog will also fix his attention the object. If I point at an object, a cat or primate will look at my finger, however the dog will often follow the gesture to the object I am pointing at.

This unique ability to understand visual and auditory commands and correlate them to our desired actions allows dogs to herd stock, retrieve and run agility courses with split second responses to our commands or, in some instances, simply to our field of focus. Top agility handlers guide their dogs across the course by aiming their body at the next obstacle. Handler error occurs when the handler accidentally pulls the dog off course by aiming his body at the wrong obstacle.

Dogs are also the only species that has demonstrated the ability to learn words on the same level as two year old human children; with the average dog being able to learn between 150-250 words.

Even more remarkable, dogs use an inferential strategy that employs the principle of exclusion. Dogs taught words for specific objects can infer, by excluding the known sound/object associations, that a new sound belongs to a new object that has been added to the mix of objects to be retrieved. Only human children have demonstrated this ability so far.

And beyond that, two border collies have demonstrated the capacity for iconicity. These dogs can be shown a two dimensional representation of an object, and then retrieve that object based on the symbol or icon represented in the image.

Is this puppy laughing?

Source: By Naomi Ibuki 

Do Dogs Have Human Feelings?

Laughter: We know dogs can bark for joy, but can they laugh too? Researcher Patricia Simonet from Sierra Nevada College and her team discovered that “certain breathy, excited exhalations” could be the canine version of laughter. Her team recorded the sounds made by dogs at play at a local park. They discovered a unique exhalation that was different from normal panting. When the team played these sound recordings for other dogs, they began to play too when the “laughing pant” was audible. Additionally, they found that playing recordings of the laughing pant helped to calm shelter dogs under stress.

Do Dogs Grieve?

Researchers have found in multiple experiments, that dogs do experience grief when a member of the household passes away. Dogs experience lethargy, loss of appetite and sleep disturbances, just as people do, for the loss of human or pet family members. Typically these manifestations of grief will last 2 weeks, but may be extended as long as six months.

Canine Jealousy and Their Sense of Fair Play

Dogs taught to shake hands for intermittent rewards will stop shaking hands if they see that another dog is receiving rewards for every hand shake. This demonstrates a sense of fair play, as well as a sense of injustice. Dogs do become jealous and even resentful, when they feel another animal is being treated better than they are.

Dogs can empathize and feel jealousy.

Can Dogs Experience Empathy?

Empathy, the ability to experience the thoughts and feelings of others has long been considered a unique trait among the higher level primates. Can dogs experience our emotions?

Yawning is not only contagious among humans, it is between humans and dogs too. A study by Teresa Romero and colleagues from the University of Tokyo found that dogs yawned when both strangers and their owners yawned. However, they responded with reciprocal yawns more frequently to their owner’s yawns than to those of strangers. The dogs also responded much less frequently to faked yawns.

Yawning is important as it demonstrates the capacity for empathy, and has been shown to correlate with the level of social attachment in several primate species. The fact that dogs differentiate between real and faked yawns and respond accordingly is intriguing. Dogs empathize with the genuine human act, and the faked one is largely ignored.

So, Do Dogs Feel Guilt?

Conventional wisdom says dogs cannot feel higher emotions such as shame or guilt. These guilty expressions are generally attributed to fear or confusion.

However in a survey, 74% of dog owners believed that their dogs experienced guilt when the knew they had transgressed. And 60% of these dog owners said that the guilty expression resulted in less scolding of the dog.

We know from the previous experiment that scolding elicits a guilty expression. Apparently, that guilty expression is useful to dogs to alleviate some of the scolding; it is an adaptive behavior. But do dogs act guilty when they know they have transgressed, yet their owner has not yet discovered the crime?

The full answer to that question has not been proven in an experiment, however one preliminary test shows that there is a guilt response in truly guilty dogs.

In an experiment led by Julie Hecht at Eotvos Lorand University in Budapest, researchers found again that all dogs act guilty when scolded for stealing forbidden food, regardless of their guilt or innocence. However, when owners left the room and then returned to greet their dogs a second time, only the dogs who were truly guilty of stealing a treat continued to act guilty on their owner's return. The innocent dogs had forgotten the scolding incident, and greeted their owners normally.

It stands to reason that animals so attuned to us, and with such an incredible capacity to learn and desire to please, would be able to anticipate our displeasure upon discovery of their crime. The Hecht Research Group is working on a new experiment to remove some of the confounding variables introduced in the lab setting. We expect that they will find further evidence that dogs do feel guilt, along with the many other human emotions they may experience.

Citations

Horowitz A (2009). Disambiguating the “guilty look”: salient prompts to a familiar dog behaviour. Behavioural processes, 81 (3), 447-52 PMID: 19520245

Public Library of Science. "Dogs yawn more often in response to owners' yawns than strangers." ScienceDaily. ScienceDaily, 7 August 2013. <www.sciencedaily.com/releases/2013/08/130807204847.htm>.

Citation: Horn L, Huber L, Range F (2013) The Importance of the Secure Base Effect for Domestic Dogs – Evidence from a Manipulative Problem-Solving Task. PLoS ONE 8(5): e65296. doi:10.1371/journal.pone.0065296

Hecht, J., et al., Behavioral assessment and owner perceptions of behaviors associated with guilt in dogs. Appl. Anim. Behav. Sci. (2012),doi:10.1016/j.applanim.2012.02.015

Truly Guilty Dogs and Their Crimes

When to Contact the Vet

You should contact the vet under any of the following circumstances:

• Diarrhea persist for 2 or more days
• Blood in the Feces
• Refusal to Eat or Drink after one day
• Pale or tacky gums
• Vomiting
• Pain
• Depression or lethargy 

Osteosarcoma in Dogs: Diagnosis, Treatment and Outcomes

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Osteosarcoma in Dogs: Diagnosis, Treatment and Outcomes

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Great Dane and Chihuahua Skeletons
Courtesy of Wikimedia Commons

While Osteosarcoma represents just 5% of all canine tumors, it is estimated that between 6000 and 8000 new cases will be diagnosed this year in the United States. As the most common type of bone cancer in dogs, Osteosarcoma accounts for approximately 85% of canine tumors that originate in the skeletal system. This is an aggressive cancer where malignant tumors develop deep within the bone; from there they destroy healthy bone and remodel it with tumorous bone from the inside out.  The tumerous bone becomes increasingly painful and is not as strong as healthy bone, potentially causing the bone to break easily with minor injury.

Risk Factors Associated With Development of Osteosarcoma In Dogs

Osteosarcoma is generally a disease of large breed dogs, and although any size dog may develop the disease, it is estimated that large breeds such as the Scottish Deerhound are 200 times more likely to develop the disease than are toy breeds. High risk breeds include Rottweilers, Deerhounds, Greyhounds, Great Pyrenees and Mastiffs as well as other large breed dogs.  Typical age of onset is 7-10 years of age, however large breeds may develop the disease earlier, in fact there have been large breed cases with diagnosis as early as under one year of age.

Factors that are suspected in increasing risk of developing the disease in addition to breed size include puppy diets that promote rapid puppy growth, spay and neuter, genetics and environmental factors:

• As tumors are frequently found near growth plates, factors that affect the growth rate and promote rapid growth are suspected in increasing likelihood of developing this cancer. 
• One long term historical study of Rottweilers showed that the earlier that a puppy was spayed or neutered the more likely it was to develop Osteosarcoma. Casterated males are 65% more likely to develop this cancer than intact males, and spayed females are 35% more likely to develop the disease than intact females.
• As certain lines of dogs within breeds have an increased propensity for developing this cancer, a genetic component is suspected as well.
• Fluoridation of drinking water has been linked to the development of Osteosarcoma in studies of both rats and young men in the North Eastern United States.

Diagnosis of Oesteosarcoma

Symptoms of Osteosarcoma will vary based on the location of the primary tumor. As the tumor grows, the affected area becomes increasingly painful. Swelling eventually develops around the tumor and the area is painful to the touch. 

• Development of a tumor in a leg bone may cause sudden onset lameness or intermittent lameness over a period of several weeks.
• Dog with tumors in their jaw bones may exhibit difficulty swallowing and/or excessive drooling. 
• Dogs with cranial or spinal tumors may present with neurologic deficits. 
• Dogs with pelvic tumors may exhibit difficulty defecating as their primary symptom.

It is important to see a veterinarian as soon as you suspect the disease, as it progresses very rapidly.  In most instances once a diagnosis of Osteosarcoma has been made, it has already micrometastasized to other areas of the body including the lungs and other bones.  Additionally, as the tumorous bone is weaker than normal bone, it can fracture easily.  Pathological fractures resulting from Osteosarcoma will not heal, so it is important to begin treatment as soon as possible.

Diagnosis is initially made by x-ray.  Once a bone tumor is suspected, the veterinarian should take x-rays of the lungs as well to see if the tumor has metastasized to that area.  Prognosis and treatment options will vary greatly if metastasis is evident in the lungs.  The tumor will also be aspirated with a small needle to obtain a sample of the tumor for further analysis and determination of the nature of the tumor.  This procedure does carry a small risk that the aspiration of the tumor could fracture the already weakened bone.

Additionally, the vet may aspirate the lymph nodes or any skin masses, do a full blood panel and perform an abdominal ultrasound in order to determine the spread of the cancer and overall health of the dog.  A bone scan may be performed in order to determine the spread of the disease to other bones and the extent of the tumor in the primary location.

Treatment For Osteosarcoma

The standard of care for the treatment of Osteosarcoma requires that the tumor be removed to prevent further spread of the disease.  In most instances, this means amputation of the affected limb.  Dogs typically respond well to this treatment, however overweight dogs, arthritic dogs or elderly dogs may not be good candidates for amputation. 

If the tumor has not progressed too far, a limb sparing procedure may be attempted.  The most successful procedures are performed where the tumor is on the bone just above the wrist of the dog and the tumor is still relatively small in size. Generally in these procedures, the removed bone must be replaced with bone from another site on the dog or from a bone bank.  Since there is a high complication rate with this procedure and a longer, more involved recovery than an amputation, amputation may eventually be necessary anyway.

In cases where neither amputation nor limb sparing procedures can be performed, the dog may be treated with palliative radiation therapy.  While radiation will not extend the life of the dog, it can be an effective pain management tool to improve the quality of the remaining life of the dog. This treatment provides relief to approximately 75% of the dogs that receive this therapy.  Radiation doses are given 1 to 4 times and are usually administered at one week intervals.

Follow-up to surgical removal of the tumor or limb includes chemotherapy.  In most instances the tumor has already micrometastisized at the time of diagnosis.  Chemotherapy, while not effective in treating tumors with visible signs of existence, is effective at destroying the microscopic disease.

Updated 11/5/13: Breakthrough in Pain Management for Dogs Suffering with Osteosarcoma

Prognosis After Treatment For Osteosarcoma

Following surgery, dogs that do not receive chemotherapy can expect an average life span of an additional 3 months post surgery.  Those treated with chemotherapy may enjoy a median lifespan of one year.  Approximately 50% treated with both surgery and chemotherapy will survive 1 year, less than 30% will survive two years and 10% will make it to 3 years.  While these statistics sound discouraging, it is important to keep in mind that in dog years, and especially in large breeds with shorter life expectancies, an additional year represents between 10-13% of a dog’s total expected life span.

Improving Your Dogs Odds In Preventing Development Of Osteosarcoma

If you have a large breed dog, or are aware that this issue has developed within your dog’s lines, there are some precautions you can take to improve his odds at heading-off or delaying the onset of the disease.

• Feed your puppy an “all life stages” dog food, and not a specially formulated puppy food that will accelerate growth.
• Wait until your dog is at least one year old before spaying or neutering him or her.  Leave males intact if you have a well fenced yard and no intact females in the home.
• Provide spring water for drinking water for your dog; carbon based filters such as PUR and Brita do not remove fluoride.
• Regularly examine your dog while petting for lumps and sensitive areas as he ages.