Research shows specific dog breeds predisposed to ‘aggressive’ cancer

Researchers have found several dog breeds are predisposed to being diagnosed with a fast-growing and often fatal cancer.

RVC researchers analysed data from the college’s VetCompass programme to assess a range of risk factors for diagnosis of canine haemangiosarcoma, from breed, bodyweight and age to sex and neuter status, practice location and socioeconomic status.

The study compared 788 clinically diagnosed cases in dogs aged at least five years old – spanning 92 individual breeds – with 1,064,187 controls. It found that 10 breeds had increased odds of clinical diagnosis compared to cross-breeds; dogue de Bordeaux was 9.56 times more likely, followed by the flat-coated retriever (8.33), German shepherd dog (6.35) and Hungarian vizsla (5.49).

In a subset of histopathologically confirmed cases, the flat-coated retriever was 17.46 times more likely; Hungarian vizsla (6.97) and German shepherd (5.18) also had increased odds, as did the beagle (4.42).

Weight categories

The median adult bodyweight of clinical cases was 26.4kg. Dogs weighing less than 7.5kg had reduced odds (0.35) compared to those between 7.5kg and 15kg, while odds increased with each weight category up to the highest of 4.42 times for those weighing 37.5kg or more.

Compared with dogs aged between seven and nine, dogs aged 11 to 13 were almost three times as likely to be diagnosed (2.83), while those aged five to seven had reduced odds at just 0.22. The median age at first diagnosis was 10.5 years.

The researchers also found that neutered males (1.49) and neutered females (1.28) had increased odds compared to entire females, although the cause of these differences is said to be unclear.

Dogs attending clinics in the least deprived areas were 1.66 times more likely to receive a clinical diagnosis than those in the most deprived areas, although deprivation level was not found to be associated with a histopathological diagnosis.

Meanwhile, dogs attending clinics in mixed urban/rural areas were at reduced odds (0.71) of a diagnosis compared to those in urban areas, with the authors calling for further research into specific pollution levels and the frequency of veterinary care by land type.

‘Important patterns’

Paper author Sandra Guillen, senior veterinary oncology lecturer at the RVC, said: “This study highlights important patterns in the diagnosis of haemangiosarcoma in dogs across the UK, and the findings not only shed light on the epidemiology of this aggressive cancer, but also raise important questions about how demographic, geographic and socioeconomic factors shape canine health outcomes.”

Lead author and RVC canine epidemiologist Georgina Barry added: “Haemangiosarcoma can be a challenging cancer to confidently diagnose in first opinion practice when timing is of the essence.

“Dogs often present very unwell, and it can be an incredibly emotional and distressing time for owners to make big decisions over their dog’s care.

“We hope these findings will support first opinion vets in guiding diagnoses to support owners and provide the most appropriate care for their canine patients in a timely manner.”