1. Oncogenesis & Progression from Actinic Keratosis
Cutaneous Squamous Cell Carcinoma (cSCC) is the second most common human malignancy, derived from atypical epidermal keratinocytes. UV-induced TP53 mutations drive malignant transformation through a continuum from actinic keratosis to cSCC in situ (Bowen's disease) and invasive cSCC.
2. High-Risk Features & Metastatic Evaluation
Tumors with diameter >2cm, invasion beyond subcutaneous fat (Breslow depth >4mm or Clark Level IV-V), perineural invasion, or immunosuppression require staging for regional lymph node metastasis.
3. Curative Interventions
Standard surgical excision with 4–6mm margins for low-risk lesions, Mohs micrographic surgery for facial tumors, and checkpoint inhibitors (Cemiplimab, Pembrolizumab) for advanced metastatic disease.