Understanding Squamous Cell Carcinoma Pathophysiology
Squamous cell carcinoma arises from the malignant transformation of keratinocytes. In many cases, these tumors appear as thickened, irregular masses that quickly ulcerate. This is distinct from Lymphoma, which often involves systemic immune system involvement. Understanding the specific location of the tumor—whether it is cutaneous or mucosal—is the first step in determining prognosis.
Solar Radiation and Cutaneous SCC
In cats with white ear tips or nose leather, chronic exposure to UV light creates DNA damage, predisposing the skin to cancerous changes. This is different from the developmental factors seen in Feline Injection Site Sarcoma, as the damage is environmental rather than reactive to medication.
Clinical Manifestations and Diagnostic Assessment
Owners often notice a 'sore' that will not heal. This is the hallmark sign of SCC. Other tumors, such as Fibrosarcoma, may feel like deep, firm nodules, while SCC often presents as a surface-level, crusty ulcer.
Diagnostic Protocols
Veterinarians will typically perform the following:
- Fine needle aspiration: To collect cells for cytological review.
- Incisional Biopsy: The gold standard to differentiate SCC from inflammatory conditions or other tumors like Melanoma.
- Imaging: Radiographs and CT scans to assess for skeletal invasion or metastasis.
Surgical and Adjunctive Treatment Modalities
Because SCC is highly invasive, surgical excision with wide margins is the treatment of choice. In areas like the jaw, this may involve mandibulectomy. When surgery cannot remove all cells, radiation therapy becomes a primary tool. Chemotherapy is generally less effective for SCC compared to its role in Biliary Carcinoma or Hepatocellular Carcinoma.
