Understanding_the_genetics_of_feline_HSA

Hemangiosarcoma (HSA, also known as malignant hemangioendothelioma or angiosarcoma) is a common solid tumour in dogs. Arising from vascular endothelium, HSA may originate from any vascular site in the body, with the most recognized primary forms affecting the spleen (28–50%), right atrium (3–50%), and skin/subcutis (13%). Hallmarks of visceral HSA (affecting the spleen and heart) include rapid dissemination and early distant metastasis, whereas cutaneous HSA is often associated with less aggressive biologic behaviour. Since visceral HSA is associated with rapid dissemination, the question remains whether cases that present with HSA tumour masses in both the spleen and heart represent metastatic dissemination of a primary mass or two independent primary masses. To answer this question, we are performing targeted exome sequencing of canine tumour-normal trios of splenic and cardiac HSA tumours from formalin-fixed, paraffin-embedded (FFPE) blocks. Since there are subtle clinical differences between cutaneous HSA tat arises in the dermis versus the subcutis, the question arises if there are genetic differences between tumors at the different sites. To answer this question, has better prognosis than visceral HSA, however, cutaneous HSA can arise in diferent locations (dermis versus cutis), and there are subtle clinical differences in outcome between these sites. To answer this question, we are performing targeted exome sequencing of canine and feline tumour-normal pairs of subcutaneous HSA tumors of dermal or subcutis location from formalin-fixed, paraffin-embedded (FFPE) blocks.