New studies reveal that oestrogen has a much deeper impact on canine mammary cancer than first thought and goes some way to enlightening us on why aggressive cancers are more likely to develop in dogs that were spayed when they were very young.
Scientists at the Penn Vet University investigated the associations and explored the correlation between the hormonal aspects and other prognostic aspects like histology, and their effect and consequences for dogs with mammary carcinomas. The researchers discovered that higher serum oestrogen levels were protective in spayed animals with mammary tumours and therefore lessens the risk of them succumbing to mammary cancer, but also drew the conclusion that spaying them could lead to a higher risk of more aggressive cancers.
A veterinary oncologist at Penn Vet and senior study author, Karin Sorenmo, stated: “Dogs that remain intact and have their ovaries develop many more mammary tumours than dogs that were spayed, so removing that source of oestrogen does have a protective effect. Oestrogen does seem to drive mammary cancer development. But what it does for progression to metastasis, that I think is more complicated. Much of the research we do in veterinary medicine looks at what is done in people and then adapts it. But dogs are such a great, comprehensive model for cancer. Yes, there are differences in biology between dogs and people, but here those differences may allow us to ask very probing questions about what oestrogen is doing in both dogs with mammary cancer and women with breast cancer.”
From Zenopa
