Prevalence and prognostic value of c-kit and TP53 mutations in canine mast cell tumours.

Highlights • The c-kit gene mutations known as drivers in canine mast cell tumours were detected in 19.5% (n = 8/41) samples. • TP53 mutations were detected in 14.6% (n = 6/41) of canine mast cell tumour specimens. • The presence of c-kit gene mutations was correlated with high histopathological grade (P = 0.038). • There was no correlation between TP53 mutations and histopathological grade or survival time (P > 0.05). Abstract Cutaneous mast cell tumours (MCT) are among the most frequent malignancies in dogs. Their clinical behaviour is highly variable and, with the exception of mutations in the c-kit gene, little is known about their genetic aetiology. The mutational status of the c-kit exons 8, 9 and 11, and exons 5–8 of the TP53 gene was analysed to find markers for molecular stratification of MCTs and predictors of clinical outcome. Mutations in the c-kit gene were detected in 19.5% (n = 8/41) samples and their presence was significantly associated with the high histopathological grade (P = 0.038). Mutations in the DNA binding domain of the TP53 gene were found in 14.6% (n = 6/41) of the analysed MCTs, and their frequency was similar in low and high grade MCTs (P > 0.05). TP53 mutations were not useful prognostic factors in this sample of canine cutaneous MCTs. [ABSTRACT FROM AUTHOR]