Cutaneous Squamous Cell Carcinoma (CSCC)

Understanding Cutaneous Squamous Cell Carcinoma (cSCC)

Cutaneous squamous cell carcinoma (cSCC) is a cancer that arises from the squamous cells of the epidermis and is the second most common keratinocyte carcinoma after basal cell carcinoma. Most cSCCs are localized and curable with surgery or radiation; a smaller subset is high‑risk for recurrence, regional spread, or metastasis.

Common Signs and Symptoms

General symptoms

• A scaly or crusted patch, a firm dome‑shaped nodule, or a non‑healing ulcer.
• Lesions may bleed, crust, itch, or become tender.
• In situ cSCC (Bowen disease) presents as a persistent red scaly patch.

Advanced or Regional Features

• Rapid growth, fixation to deeper tissues, regional lymphadenopathy, or systemic symptoms (weight loss, persistent pain) suggest more aggressive disease and warrant urgent evaluation.

Causes and Risk Factors

Key risk factors include cumulative ultraviolet (UV) radiation exposure, fair skin, older age, immunosuppression (including organ transplant recipients), prior radiation, chronic wounds or scars, and certain genetic conditions. A history of actinic keratoses or prior skin cancer increases risk.

Diagnosis and Staging

Diagnosis is established by skin biopsy (shave, punch, or excisional) with histopathologic confirmation. Evaluate for high‑risk features (tumor size, depth, perineural invasion, poor differentiation) to guide staging and management. Imaging and sentinel lymph node assessment are considered when regional spread is suspected. Staging systems such as AJCC are used to stratify risk.

Treatment overview

Localized disease

• Surgical excision with appropriate margins or Mohs micrographic surgery is the standard curative approach for most cSCCs. Radiation therapy is an alternative when surgery is not feasible.

High‑risk or advanced disease

• Multidisciplinary care (dermatology, surgical oncology, radiation oncology, medical oncology) is recommended for high‑risk tumors.
• Systemic therapy, including immune checkpoint inhibitors targeting the PD‑1/PD‑L1 pathway, is an established option for locally advanced or metastatic cSCC that is not amenable to curative surgery or radiation.

Supportive care

Supportive measures include wound care, dermatologic surveillance, sun‑protection counseling, and rehabilitation for functional deficits. Regular skin checks and patient education about new or changing lesions are essential because patients remain at increased risk for additional skin cancers.