Squamous cell carcinoma (SCC) is a malignant tumor derived from epithelial cells. The skin, oral cavity, and toes 🐾 are the most common areas of occurrence in dogs and cats 🐶🐱.
For skin tumors, SCC occurs in 15% of cats. Most cases develop on the head, often affecting the auricle, eyelids, and nose 👂👀🐱.
However, less than 5% of skin tumors in dogs are SCC, most commonly appearing on the extremities, scrotum, and nose 🐶.
For oral tumors, SCC accounts for 70% of cases in cats and 25% in dogs 🦷.
For toe tumors, SCC occurs in 38% to 50% of cases in dogs, but is rarely seen in cats’ toes 🐾.
Most SCC cases are locally invasive and may deeply infiltrate the bone 🦴. While metastasis through lymph nodes is possible, sporadic spread is rare unless the tumor is in an advanced stage ⚠️. However, certain locations, such as the lungs, toes, and chest line, have a higher metastasis rate .
The exact cause of SCC is not fully understood, but studies suggest a strong link to ultraviolet exposure 🌞. This explains why SCC is more prevalent in areas with less fur or lower melanin levels.