Basal-cell tumor is the most common skin cancer in animals. It rarely metastasizes or kills. However, because it can cause significant destruction and disfigurement by invading surrounding tissues, it is still considered malignant. This is a common tumor usually found on the head and neck in dogs over 7 years of age. It appears as a firm, solitary nodule with distinct borders that sets it apart from the surrounding skin.
The tumor originates in the epithelial cells, which are the cells that make up most of the top layer of skin (the epidermis). Basal cell tumors are usually benign, although about 10% are malignant.
Although the condition is not breed specific and can affect dogs of any breed, age and size, Cocker Spaniel and Poodles carry a higher risk of this skin disorder.
A basal cell tumor will appear as a round, raised and hairless bump (0.2 to 10 cm in diameter). These tumors occur most frequently on the dog’s head, neck or shoulders. Only 10% of basal cell tumors are malignant (e.g., basal cell carcinoma).