Feline paediatric oncology: retrospective assessment of 233 tumours from cats up to one year (1993 to 2008).

Objectives: To determine which types of tumour occur in cats up to the age of 12 months based on biopsies submitted to Idexx Laboratories, Wetherby, UK.
Methods: Retrospective review of histopathological diagnoses of tumours in cats up to the age of 12 months from biopsies received between September 1993 and March 2008.
Results: A total of 4196 submissions from cats 12 months old or younger were identified; 233 biopsies (6%) were neoplastic and fulfilled the search criteria. Tumours were categorised as haematopoietic (n=73, 31%), malignant epithelial (n=44; 19%), malignant mesenchymal (n=38; 16%), benign epithelial (n=37; 16%), benign mesenchymal (n=30, 13%) and miscellaneous (n=11; 5%). The most frequent tumours were lymphoma (n=51; 22%), soft-tissue sarcoma (n=34; 15%), mast cell tumour (n=22; 9%) and squamous cell carcinoma (n=16; 7%). The most common tumour site was the skin and soft tissues (41% of tumours). In all, 164 neoplasms (70%) were malignant or had malignant potential.
Clinical Significance: These data provide unique epidemiological information on a poorly characterised subgroup of feline cancer patients in the UK.