Companion Animals

Dog Mammary Tumour Prevention Through Neutering

Mammary tumours are the most common cancer in intact female dogs, and neutering significantly reduces their risk.

Key Facts

Approximately 50% of mammary tumours in dogs are malignant
Spaying before the first season reduces mammary tumour risk to near zero
Spaying after the first season still reduces risk but less dramatically than early neutering
Diagnosis requires biopsy and staging, with surgical removal as first-line treatment
Metastatic disease carries a poor prognosis and significant quality of life impact

Welfare Considerations

Mammary cancer causes substantial pain and suffering in affected dogs. Prevention through early spaying is highly effective and avoids the welfare burden of cancer diagnosis, surgery and potential euthanasia. Owners and breeders need clear information about the benefits of neutering for cancer prevention.

What You Can Do

Discuss the timing of neutering with your vet to balance cancer prevention and developmental considerations
Check your female dog regularly for mammary lumps as she ages
Seek prompt veterinary assessment if any lumps are found
Support organisations providing neutering assistance for low-income pet owners