SciRouter Oncology / Cancer guide / Osteosarcoma
Canine cancer guide

Osteosarcoma

Aggressive bone cancer, typically appendicular (limb), with very high rate of micro-metastatic spread to lungs by the time of diagnosis. The closest canine analog to pediatric human osteosarcoma — and a key translational model.

also known as OSAalso known as Bone cancer
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Prevalence

~85% of canine bone tumors. ~8,000–10,000 cases per year in the US. Disproportionately affects giant breeds: Greyhounds, Rottweilers, Great Danes, Irish Wolfhounds, Saint Bernards.

Who gets it

Bimodal: young giant breeds (~2 years) and middle-aged large breeds (~7 years). Risk scales with body weight. Spayed/neutered before puberty may slightly increase risk.

Symptoms to watch for

  • Lameness that doesn't resolve with rest
  • Swelling or pain at the affected bone (usually distal radius, proximal humerus, distal femur, proximal tibia)
  • Pathologic fracture in advanced cases
  • Sometimes only subtle limping at first

How it's diagnosed

  • Radiographs of the painful limb — classic 'sunburst' lytic-proliferative pattern
  • Three-view chest radiographs OR chest CT to assess for pulmonary metastases
  • Bone biopsy (Jamshidi or open) for histopathologic confirmation
  • Alkaline phosphatase — elevated ALP is a poor prognostic factor
  • Optional: bone scan / staging CT

Prognosis ranges

Amputation alone: median survival 4–5 months. Amputation + carboplatin chemotherapy: median 10–12 months, ~20% alive at 2 years. mRNA-LNP neoantigen vaccine + checkpoint inhibitor (UF Sayour/Milner trial) is a major active research front.

Treatment landscape

Limb amputationSurgery
ResponseEliminates primary disease; doesn't affect metastases
ToxicityMost large dogs adapt within 2–4 weeks. Limb-sparing alternatives exist at academic centers.
Cost range$3,000–$6,000
Carboplatin (4–6 cycles)Chemotherapy
ResponseRoughly doubles median survival vs surgery alone
ToxicityMyelosuppression; well-tolerated in dogs.
Cost range$3,000–$5,000
Stereotactic radiosurgery (limb-sparing)Radiation
ResponseComparable to amputation in selected cases
ToxicityRisk of pathologic fracture; available at CSU, PetCure.
Cost range$8,000–$15,000
Personalized mRNA neoantigen vaccine + checkpoint inhibitor (investigational)Vaccine
ResponseActive trials at UF; canine glioma data showed nearly doubled survival vs vaccine alone
ToxicityMild local reactions; CRS risk requires monitoring.
Cost rangeTrial-funded today; $8K–$15K projected at v3

Recurrent mutations in this cancer

Frequencies from canine clinico-genomic cohorts. SciRouter Oncology auto-checks every mutation in your dog's report against the OncoKB-aligned database for matched targeted therapies.

GeneFrequency
TP53
38%
PTEN
18%
RB1
9%
MET
7%

Questions to ask your vet

  • Was this confirmed on biopsy or just radiographs?
  • What's the ALP value? Is it elevated?
  • Do we have chest CT staging? Any pulmonary nodules?
  • What's the fracture risk on the affected limb?
  • Are there clinical trials enrolling? (Especially UF mRNA, CSU, Penn.)
  • What's the pain plan? Bisphosphonates? Opioids?

Quality-of-life notes

Pain control is the most important QoL lever before and after treatment. Bisphosphonates (zoledronate, pamidronate) reduce bone pain. Most dogs adapt well to amputation — large dogs more easily than tiny ones.

Other canine cancers