+ HEMANGIOSARCOMA
- Prevalence of dermal HSA in cats is highly variable ranging from none to most common site of HSA
- HSA often occurs in unpigmented skin or white cats due to exposure to ultraviolet light
- Sex predisposition: male
- Median age 12.5 years
- Site predilection: dermis and subcutis of head (especially pinna) or inguinal subcutis
- Tumor cells are immunoreactive to factor-VIII related antigen and vimentin
- Treatment: wide surgical excision as traditionally unresponsive to chemotherapy and relatively radioresistant
- Prognosis is guarded with local tumor recurrence rate of up to 50% following histologically complete resection and metastatic rate of up to 25% at the time of diagnosis
+ HEMANGIOMA
- Sex predisposition: male
- Median age 10 years
- Pigmented skin with no site predilection although other papers report a predilection for white-haired areas
- Tumor cells immunoreactive for factor-VIII related antigen and vimentin
- No local tumor recurrence following complete resection