Squamous cell carcinoma of the skin 

Squamous cell carcinoma of the skin (SCC) is the second most common malignant skin tumor after basal cell carcinoma. It arises from the keratinocytes of the epidermis and has the potential for local invasion and metastasis, especially in aggressive forms or locations.

Risk factors
- Chronic exposure to ultraviolet (UV) radiation
- Actinic keratosis (precancerous condition)
- Light skin phototype
- Advanced age
- Immunosuppression (e.g. after transplantation)
- Chronic inflammation, ulcers, burns, radiation damage
- Human papillomavirus (HPV) – especially in genital and perineal locations

Clinical picture
- Flat, red or hyperkeratotic plaque
- Nodular raised formation with crusts or ulceration
- Often localized to areas exposed to the sun: face, ears, scalp, hands
- May bleed or be painful
- In advanced cases – infiltration of underlying tissues or lymph nodes

Differential diagnosis
- Basocellular carcinoma
- Actinic keratosis
- Keratoacanthoma
- Psoriasis, chronic dermatitis
- Melanoma (especially amelanotic)

Diagnosis
- Clinical examination by a dermatologist
- Dermatoscopy – hyperkeratosis, vascular structures, white areas
- Histological confirmation by biopsy or excision
- Imaging studies (ultrasound, CT scan) in case of suspected invasion or metastasis

Staging and prognostic factors
- Tumor size (>2 cm)
- Depth of invasion (>6 mm or below the dermis)
- Perineural or vascular invasion
- Immunosuppression
- Anatomical localization (lips, ears, genitals)

Treatment
- **Surgical excision** with oncological margin – gold standard
- **Mohs micrographic surgery** – for aggressive or recurrent tumors
- **Electrocoagulation and curettage** – for small, superficial lesions
- **Cryotherapy** – for pre-invasive forms
- **Radiotherapy** – in inoperable or elderly patients

Forecast
The prognosis is excellent with early diagnosis and adequate treatment. Metastases occur in <51% of cases, but the risk is higher in aggressive forms, immunocompromised patients, or involvement of high-risk areas.

Squamous cell carcinoma is a potentially aggressive skin tumor, but with early diagnosis and treatment, the outcome is favorable. Regular dermatological examinations and sun protection are essential elements in prevention and early detection.