Last Updated: 21/01/2026
Osteosarcoma in Dogs: A Complete Guide to Bone Cancer
Osteosarcoma is a common and aggressive bone cancer in dogs. Discover the key signs to watch for, which large breeds are most at risk, and how modern treatments like amputation and chemotherapy can improve your dog's quality of life and prognosis.
Author: Dr Brittany Ward BVSc
Reading Time: 9 minutes - short read
Discovering a new lump or noticing a persistent limp in a beloved dog is a moment every pet parent dreads. When that diagnosis is osteosarcoma - the most common form of bone cancer in dogs - it can feel overwhelming.
This aggressive condition primarily affects the long bones of the limbs, though it can appear anywhere in the skeletal system. While the news is difficult, understanding the disease is the first step in providing the best possible care.
This guide explores the risk factors, the diagnostic process, and the various ways to manage pain and treatment to ensure your dog remains comfortable and supported.
In this article
- What is osteosarcoma in dogs?
- Which dog breeds are most at risk of bone cancer?
- Common and early warning signs
- How vets diagnose osteosarcoma
- Understanding the stages of canine bone cancer
- Treatment options: surgery, chemo, and radiation
- Managing life after limb amputation
- Pain management and palliative care
- Prognosis and life expectancy for dogs with osteosarcoma
- FAQs
What is osteosarcoma in dogs?
Osteosarcoma is the medical term for bone cancer. By breaking down the name, we get 'osteo' for bone and the suffix sarcoma which indicates a malignant tumour.
Osteosarcomas are the most commonly occurring bone cancer in dogs and are typically diagnosed in the limbs; called appendicular osteosarcoma. However, it can occur in any bone within the body.
What causes Osteosarcoma?
Like most cancers, there is no specific cause known for Osteosarcomas. It carries the same risk factors as any other cancer, although there may be a genetic component given that some breeds are more prone to getting bone cancers.
Which dog breeds are most at risk of bone cancer?
Osteosarcomas can occur in any breed at any age, but is more commonly seen in large and giant breed dogs. Studies have found that breeds over 40kg, those with longer muzzles/skulls and longer legs are at the highest risk. However, some specific breeds tend to be over-represented in presenting cases, including:
- Scottish Deerhound
- Leonerger
- Rottweiler
- Great Dane
- Greyhound
- Boxer
- German Shepherd
- Dobermann
- Irish Setter
- Irish Wolfhound
- Bull Mastiff
- Golden Retriever
- Newfoundland
- Saint Bernard
- Rhodesian Ridgeback
Common and early warning signs
The most common symptoms of Osteosarcoma are a lump or lameness, particularly if in the limbs.
Some dogs may also present with non-specific symptoms, such as:
- Lethargy
- Loss of appetite
- Reduced activity
- Fever
- Weightloss
- Depression
- Shaking or shivering
- Breathing difficulty
- Nasal discharge
It is important to be aware of the less specific symptoms of Osteosarcoma and get your dog checked if they are showing any signs of being unwell as Osteosarcomas are often diagnosed late, reducing treatment options.
Osteosarcomas damage the affected bones and can weaken them. This can mean that the bone can break during normal activity. Some osteosarcomas may only be diagnosed when the dog presents for this fracture.
How vets diagnose osteosarcoma
Physical examination
If your pet is showing signs of Osteosarcoma, they will need to be taken to the vet. Your vet will perform a complete examination to assess their health and any visible tumours.
X-rays
If your vet suspects an Osteosarcoma, they will recommend X-rays. Osteosarcomas are cancers of bone cells, so show cancerous bone growth as well as bone destruction on an X-ray. They are often described as having a "moth-eaten" appearance. If your dog has a fracture as well, this will also be visible on X-ray.
Biopsy
While they are sedated they will sample the tumour with fine needle aspiration. This will allow them to look at the type of cells involved under the microscope and confirm the diagnosis of Osteosarcoma. Fine Needle Aspiration often cannot be done while patients are awake as Osteosarcomas are very painful.
When Fine Needle Aspirate is unsuccessful, a bone biopsy may be required for definitive diagnosis.
Understanding the stages of canine bone cancer
Before your vet makes treatment recommendations, they will stage the Osteosarcoma. There are three stages used for this condition.
This type of tumour is highly aggressive and spreads rapidly. Often at the time of diagnosis, the cancer will have already metastasised (spread) into other parts of the body (Stage III).
A common location for these is in the lungs, which is why many vets will also take chest X-rays. Sometimes micrometastases may have already formed, but may not be visible, so bloodwork, urinalysis and potentially abdominal ultrasound may also be performed.
The identification of metastases and staging, gives an indication of prognosis and suitable treatment options.
Treatment options: surgery, chemo, and radiation
There are several management options available for Osteosarcomas, depending on the stage of the condition, your dog and your circumstances. Your vet will discuss your individual dog's case and which treatments best suit their situation.
Treatment relies on managing the pain and preventing the spread of the bone cancer.
Surgery
Amputation
Limb amputation sounds scary, doesn't it? Many owners can hesitate to amputate a limb because they worry about how their dog may cope and fear the seemingly drastic change. Dogs manage exceptionally well after an amputation though!
- Fastest way to remove the extremely painful tumour and prevent the cancer from spreading
- Recovery times are quicker than other orthopaedic procedures (such as Cruciate Ligament surgery)
- Immediately removes the pain creating a sense of relief in affected dogs.
Amputation may not be a suitable option in patients with concurrent neurological concerns or severe arthritis, however, your vet will discuss your dog's suitability for this treatment with you.
Limb Sparing Surgery
Limb sparing surgery is an alternative to amputation that allows the limb to remain. In these surgeries, the affected bone is removed, leaving only unaffected bone, which is supported with a bone graft or internal fixation with plates or pins.
- Can only be used in a limited number of locations
- Typically involves fusion of the closest joint
- Cannot be performed if more than 50% of the bone is affected
- Doesn't work well in the hindlimb
- Complication risks include bone infection, implant failure, fracture and recurrence of the tumour
- Long recovery time involving ongoing cage rest
- Must be used in conjunction with chemotherapy
Chemotherapy
- Often recommended and usually in conjunction with amputation to have the most successful outcome
- Due to the aggressive nature of the cancer, most vets assume it has spread at the time of diagnosis (even without radiographic evidence), and therefore chemotherapy is required to improve prognosis
- Involves three treatments given every 3-4 weeks
- Most commonly used medications are Cisplatin, Carboplatin and Doxorubicin
- Generally only causes mild side effects: 1-2 days of lethargy and nausea post treatment. This nausea may be managed with medications
- Hair loss is very rare in animal chemotherapy patients
Radiation Therapy
- May be a treatment option for patients who are not suitable candidates for amputation
- Targets the tumour directly
- May be given as 2-4 doses, depending on your vet's treatment protocol
- Limb function can improve within 3 weeks
- Treatment may be repeated
- 75% of patients respond to radiation
Managing life after limb amputation
If your dog undergoes surgery to amputate the limb, they will need support around the house afterwards. While patients tend to do really well, it does place additional pressure on their remaining joints and they may have some reduced mobility.
To support the remaining joints, especially for senior patients with arthritis, you can use joint supplements.
Amputation patients can also struggle to get up stairs, into the car or onto beds, so will benefit from ramps that make access easier.
Provide plenty of non-slip surfaces to prevent them slipping on smooth surfaces, such as carpet and rugs.
Due to the increased pressure on their joints, a soft, comfortable bed, such as an orthopaedic bed can be essential ensuring they are well rested and their joints are rested in the morning.
Pain management and palliative care
Because osteosarcoma is an incredibly painful condition, pain relief is provided to assist with managing the condition. This is especially important in patients that have Stage III disease or poorer prognosis, or for owners who opt for palliative management at home.
Pain relief is also essential for patients who have axial osteosarcomas (those located in bones other than the limbs) as they often cannot have surgical removal.
Pain relief options include non-steroidal antiinflammatory medications such as Meloxicam ('Metacam') and Firocoxib ('Previcox'), gabapentin and opioids.
Your vet will discuss the medications available, which is best for your dog and the dosage required. They may even combine medications as disease progresses for greater pain relief.
Biophosphonates
Biophosphonates are a relatively new medication available for managing pain associated with osteosarcoma. These medications have been used in human medicine and become commonplace due to their success. The have recently started to branch into canine medicine as well.
Biophosphonates stop bone destruction, which controls the pain and prevents worsening of bone tumours.
Treatment is administered via an IV drip over 2 hours approximately every 3-4 weeks. While side effects have been seen in humans, we have not yet seen these in dogs.
This form of treatment is especially important in patients that cannot undergo amputation.
Prognosis and life expectancy for dogs with osteosarcoma
Osteosarcoma is a rapidly progressive disease so will eventually be fatal for all patients. However, there are some indicators that can determine prognosis for your dog and their likely survival time, depending on treatment option. Patients with earlier diagnosis have the greatest prognosis.
Prognosis Guidelines of Osteosarcoma from Diagnosis:
- Without therapy, the survival time is 1-3 months as the pain associated with this condition becomes too severe.
- With amputation only, survival time can be up to 6 months.
- Radiation and chemotherapy can increase survival up to 10-12 months.
- Amputation and chemotherapy combined increases life expectancy to one year or longer. 20% of patients in this category are alive 2 years post diagnosis.
- Limb sparing surgery with chemotherapy offers the same life expectancy as amputation and chemotherapy.
- Dogs with an elevated alkaline phosphatase on bloods have 50% of the survival times listed above.
- Dogs with evidence of lung metastases at the time of diagnosis have a poorer prognosis.
- Dogs with tumours in the local lymph nodes at the time of amputation also have a poorer prognosis (59 vs 318 days).
FAQs
Receiving an osteosarcoma diagnosis is undoubtedly heartbreaking, but it is important to remember that you are not alone in this journey. While the prognosis for bone cancer is serious, modern veterinary medicine offers several pathways to manage pain and extend quality time with your best friend. Whether choosing surgical intervention or palliative care, the goal is always to prioritise your dog’s comfort and happiness. By working closely with a vet, you can make informed decisions and provide a loving, supportive environment for your dog during this challenging time.
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History
Our experts continually monitor the health and wellness space and we update our articles when new information becomes available.
Thu 22 Jan 2026
Edited by Dr Gillian Hill BVSc (Hons)Dr Brittany Ward BVSc
Veterinarian
Dr. Brittany graduated from James Cook University in 2019 with a Bachelor of Veterinary Science and started working in her home town in the Wide Bay-Burnett Region. She has always been excited about working in the veterinary industry, but over the last few years has grown especially fond of dog behaviour and training, surgery and orthopaedic disease.
