Mast cell tumors in dogs
Mast cell tumors are the most common skin cancer in dogs. They range from low-grade lumps that are cured with surgery to aggressive tumors that spread.
Last updated: October 2026 · 3 sources · see sources
Signs to watch for
- A skin lump that may change size, get red or itchy
- Some look like harmless bumps
Trouble breathing, collapse, repeated vomiting, not peeing, or a seizure that lasts more than a few minutes needs a vet right away. See when to see a vet.
How vets diagnose it
A needle sample usually identifies them. After removal, the lab grades the tumor and checks the margins. [2][3]
How it's treated
Surgery with wide margins is the main treatment. Radiation, chemotherapy or targeted drugs are used for higher-grade or hard-to-remove tumors. [2][3]
Medicines your vet may mention: Prednisone & Prednisolone, Famotidine (Pepcid). We don't list doses; your vet will decide what fits your pet.
What it costs to diagnose and manage
| Item | Typical US price | Src |
|---|---|---|
| Diagnosis (exam and tests) | $500–$1,500 | [1] |
| Treatment | $1,000–$15,000 | [1] |
These are typical US ranges from the sources listed. Your pet's costs depend on how severe things are, the tests your vet recommends, your pet's size and where you live. Ask your vet for a written estimate.
Outlook
Low-grade tumors removed completely often have an excellent outlook. Higher grades need more treatment. [2][3]
Common questions
What is mast cell tumors in dogs?
Mast cell tumors are the most common skin cancer in dogs. They range from low-grade lumps that are cured with surgery to aggressive tumors that spread.
What are the signs of mast cell tumors?
Common signs include: a skin lump that may change size, get red or itchy, some look like harmless bumps.
How do vets diagnose mast cell tumors?
A needle sample usually identifies them. After removal, the lab grades the tumor and checks the margins.
How is mast cell tumors treated?
Surgery with wide margins is the main treatment. Radiation, chemotherapy or targeted drugs are used for higher-grade or hard-to-remove tumors.
How much does mast cell tumors cost to treat?
Diagnosis (exam and tests): $500–$1,500; Treatment: $1,000–$15,000. Costs vary with severity, tests, your pet's size and where you live.
Related
This page is general information for pet owners, not veterinary advice. Talk to your vet about your own pet.