Evaluation of intrinsic and extrinsic risk factors for dog visceral hemangiosarcoma: A retrospective case-control study register-based in Lazio region, Italy.

The genetic and breed susceptibility of visceral hemangiosarcoma in dogs has been studied, but there is no evidence of environmental risk factors as reported in human medicine. We conducted a case-control study in which the sampling population was the list of canine oncology cases of the Animal Tumour Registry of Lazio region, Italy (2009-2017). We defined cases as dogs with visceral hemangiosarcoma and controls as dogs affected by another neoplasm. The ratio between controls and cases was 3:1. Analysed variables were: age, weight, sex, reproductive status, size, breed, nutrition habit, living environment and location of the house. We performed a preliminary univariate analysis to select potential risk factors (p-value < 0.2) then entered in a forward stepwise logistic regression model. Ninety-three cases enrolled in the study were compared with 279 controls. The multivariable logistic regression identified age, reproductive status and breed as significant risk factors. Results showed an increasing risk with increasing age for age classes 6-10 and > 10 years old (OR = 9.69, 95 % CI: 1.21-77.62; OR = 14.01, 95 % CI: 1.65-119.03). Neutered animals (male and female) were at greater risk compared to intact ones. The breeds at greatest risk were German shepherd (OR = 4.17, 95 % CI: 1.25-13.86) and mixed breed (OR = 3.50, 95 % CI: 1.44-8.51). The last finding could be explained by the genetic origin of the animals, which may include German shepherd or another possible breed at risk. No other individual or environmental variables were identified as risk factors. The findings of this work indicate that genetic predisposition is the key element in visceral hemangiosarcoma development.

Detection of Felis catus papillomavirus type-2 DNA and viral gene expression suggest active infection in feline oral squamous cell carcinoma.

Papillomavirus (PV) infection is associated with development of epithelial cancer in different species, including domestic cat (Felis catus). Felis catus PV type-2 (FcaPV-2) is considered the causative agent of a proportion of feline cutaneous squamous cell carcinoma (SCC), through the transforming properties of its E6 and E7 oncogenes. However, the possible role of FcaPVs in the aetiology of feline oral SCC (FOSCC) is still unclear. The aim of this study was to assess the presence and gene expression of FcaPV-2 in FOSCC samples. We detected FcaPV-2 DNA in 10/32 (31%) of the analysed FOSCC by the use of PCR methods. Importantly, viral mRNA was detected by RT-PCR in 7/10 (70%) of DNA positive samples. In particular, FcaPV-2 L1, E2 and E6E7 genes were found to be expressed in 5/10 (50%), 3/10 (33%) and 5/10 (50%) samples, respectively. Viral DNA was also detected in non neoplastic oral ulcerative lesions (ULs) (4/11, 36%); qPCR suggested a difference in viral load between ULs and FOSCCs, particularly in those expressing E6E7, although it was not statistically significant. These data suggest, but do not definively prove, a possible role of FcaPV-2 in the development of a proportion of FOSCC. Moreover, L1 and E2 gene expression results indicate that FcaPV-2 infection associated with these tumours may possibly be productive.