Skin cancer, squamous cell - Symptoms, Causes, Treatment & Prevention

📅 Updated: May 2026 ⏱ 7 min read ✅ Medically reviewed
```html Skin Cancer – Squamous Cell Carcinoma (SCC) – Comprehensive Guide

Skin Cancer – Squamous Cell Carcinoma (SCC)

Overview

Squamous cell carcinoma (SCC) of the skin is the second‑most common form of non‑melanoma skin cancer, arising from the squamous cells that make up the outer layer of the epidermis. While it accounts for only about 15‑20 % of all skin‑cancer cases, it is more likely than basal cell carcinoma (the most common type) to spread (metastasize) to deeper tissues or other organs if left untreated.

Who it affects: Anyone can develop SCC, but it is most prevalent in adults aged 50 years and older. Men are slightly more likely than women to be diagnosed, and the incidence is highest among people with fair skin (e.g., types I–II on the Fitzpatrick scale) who have a history of intense or cumulative ultraviolet (UV) exposure.

Prevalence: In the United States, the American Cancer Society estimates ~700,000 new cases of non‑melanoma skin cancer each year, with SCC representing roughly 100,000–150,000 of those. The incidence is rising worldwide, largely due to increased UV exposure and aging populations (CDC, American Cancer Society).

Symptoms

SCC can appear on any sun‑exposed area, but the most common sites are the face, ears, neck, lips, dorsum of the hands, and arms. Early lesions may be painless and easily overlooked.

  • Persistent, scaly patch – Often looks like a rough, red or brown patch that does not heal.
  • Raised, flesh‑colored or pink bump – May have a central ulcer or crust.
    • Ulcerated lesion – An open sore that bleeds or oozes and does not improve with typical wound care.
  • Red or pink growth with a warty surface – Sometimes described as “wart‑like.”
  • Hard, thickened area (keratotic plaque) – Can feel “leathery.”
  • Growth that spreads outward – Edges may be poorly defined or “rolled.”
  • Changes in an existing scar or burn – A new lump or ulceration developing in a previously injured area (Marjolin ulcer).
  • Bleeding or crusting – Especially after minor trauma.
  • Pain or tenderness – Usually a late sign when the tumor invades nerves.

If any skin lesion changes in size, shape, color, or texture, or fails to heal within 2–4 weeks, it should be evaluated by a clinician.

Causes and Risk Factors

Squamous cell carcinoma is primarily driven by DNA damage to skin cells from ultraviolet radiation, but several other factors contribute.

Primary Causes

  • Ultraviolet (UV) radiation – Both UVA (aging) and UVB (burning) wavelengths cause mutations in the p53 tumor‑suppressor gene.
  • Human papillomavirus (HPV) infection – Certain high‑risk subtypes (e.g., HPV 16, 31) are linked to SCC of the anogenital region and, less commonly, the skin.

Risk Factors

  • Fair skin, red or blond hair, blue/green eyes – Low melanin provides less natural UV protection.
  • Chronic sun exposure – Outdoor occupations (farmers, construction workers) and recreational exposure (beach, skiing).
  • History of severe sunburns, especially in childhood.
  • Age ≄ 50 years – Cumulative DNA damage over time.
  • Immunosuppression – Organ‑transplant recipients, HIV infection, chronic corticosteroid use; risk can be 65‑fold higher.
  • Previous skin cancers – Basal cell carcinoma or SCC increases future risk.
  • Chronic wounds, scars, burns, or inflammatory skin conditions – e.g., actinic keratoses, lupus, lichen planus.
  • Exposure to arsenic or certain chemicals – Occupational exposure to tar, coal‑tar, or petroleum products.
  • Female genital or perianal SCC – Linked to HPV.

Diagnosis

Early detection improves outcomes dramatically. Diagnosis typically proceeds through a stepwise approach.

Clinical Evaluation

  • History and visual exam – Dermatologist notes size, color, border, texture, and location.
  • Dermatoscopy – A handheld magnifier that reveals vascular patterns and surface features suggestive of SCC.

Biopsy Procedures

Definitive diagnosis requires a tissue sample.

  • Punch biopsy – Removes a core of skin (2‑6 mm) and is suitable for most lesions.
  • Excisional biopsy – Entire lesion is removed; preferred for small, well‑defined tumors.
  • Shave biopsy – Thin slice of superficial tissue; may be used for flat lesions but can miss deeper invasion.

Pathology

Pathologists assess for atypical squamous cells, keratin pearls, and invasion depth (Breslow thickness). They also grade the tumor (well‑, moderately‑, or poorly‑differentiated) and look for perineural involvement.

Staging & Imaging

Staging follows the AJCC (American Joint Committee on Cancer) 8th edition.

  • High‑risk features (size > 2 cm, deep invasion > 2 mm, perineural invasion, poor differentiation) may warrant imaging such as ultrasound, CT, or MRI to assess nodes or metastasis.
  • Sentinel lymph node biopsy – Considered for tumors with high metastatic potential.

Treatment Options

Treatment is individualized based on tumor size, location, depth, patient health, and cosmetic considerations.

Surgical Interventions

  • Excisional surgery – Standard of care for most SCCs; removes tumor with 4‑6 mm margins (wider for high‑risk lesions).
  • Mohs micrographic surgery – Tissue is removed layer‑by‑layer, examined in real time. Offers highest cure rates (up to 99 % for facial SCC) and preserves healthy tissue.
  • Curettage & electrodesiccation – Scraping the lesion followed by cauterization; used for small, low‑risk tumors.

Non‑Surgical Treatments

  • Radiation therapy – External beam radiation for patients who cannot undergo surgery or for incompletely excised lesions.
  • Topical agents – 5‑Fluorouracil (5‑FU) or imiquimod may treat superficial SCC in situ (Bowen disease).
  • Cryotherapy – Freezing with liquid nitrogen; effective for tiny, well‑defined lesions.
  • Photodynamic therapy (PDT) – Photosensitizing agent + light activation; suitable for superficial SCC.

Systemic Therapies (Advanced/Metastatic SCC)

  • Immune checkpoint inhibitors – Cemiplimab (PD‑1 inhibitor) and pembrolizumab have shown durable responses in metastatic or locally advanced SCC (NIH).
  • Targeted therapy – EGFR inhibitors (cetuximab) may be used in select cases.
  • Chemotherapy – Platinum‑based regimens (cisplatin + 5‑FU) for patients not eligible for immunotherapy.

Lifestyle & Supportive Measures

  • Wound care after surgery (clean dressings, infection prevention).
  • Smoking cessation – smoking impairs wound healing and is a known risk factor.
  • Regular skin examinations – self‑checks and professional visits.

Living with Skin Cancer – Squamous Cell Carcinoma

Managing SCC after treatment involves vigilance, skin protection, and emotional support.

Daily Skin Care

  • Use a broad‑spectrum sunscreen (SPF 30 or higher) daily; reapply every 2 hours when outdoors.
  • Wear protective clothing, wide‑brim hats, and UV‑blocking sunglasses.
  • Avoid tanning beds and seek shade between 10 am–4 pm.
  • Inspect your skin every morning and night; use a mirror or ask a partner to check hard‑to‑see areas.

Follow‑up Schedule

Most dermatologists recommend:

  • First postoperative visit within 1‑2 weeks.
  • Subsequent visits every 3‑6 months for the first 2 years, then annually.

Bring any new or changing lesions to the appointment.

Psychosocial Well‑being

  • Join support groups (e.g., Skin Cancer Foundation community).
  • Consider counseling if you experience anxiety about recurrence or cosmetic concerns.
  • Maintain a balanced diet rich in antioxidants (fruits, vegetables) to support immune health.

Prevention

Prevention focuses on reducing UV exposure and early detection.

Sun‑Safety Practices

  • Apply sunscreen 15 minutes before going outside; use at least 1 ounce (a shot‑glass full) for full body.
  • Choose “broad‑spectrum” labeled products (protect against UVA and UVB).
  • Wear UPF 50+ clothing, especially for outdoor work.
  • Seek shade whenever possible.

Behavioral Modifications

  • Stop smoking – it increases skin‑cancer risk and hampers healing.
  • Limit use of photosensitizing medications (e.g., tetracyclines, thiazide diuretics) after discussing alternatives with your doctor.
  • Regularly treat actinic keratoses (precancerous lesions) with cryotherapy or topical agents to prevent progression.

Screening Recommendations

  • Adults ≄ 35 years with a history of extensive sun exposure should have a full‑body skin exam by a dermatologist every 1‑2 years.
  • High‑risk groups (organ‑transplant recipients, immunosuppressed, prior SCC) need exams every 6‑12 months.

Complications

If SCC is not treated promptly, several serious complications can arise.

  • Local invasion – Tumor can erode into muscle, cartilage, bone, or underlying organs, especially on the nose, ear, or lip.
  • Perineural spread – Cancer tracks along nerves, causing pain, numbness, or facial muscle weakness.
  • Regional lymph‑node metastasis – Approximately 5‑10 % of SCCs spread to nearby nodes; associated with a 5‑year survival < 70 %.
  • Distant metastasis – Rare (<1‑2 %) but can affect lungs, liver, brain, or bone.
  • Functional and cosmetic deficits – Large resections may require reconstructive surgery, affecting speech, vision, or appearance.
  • Psychological impact – Anxiety, depression, or body‑image issues after treatment.

When to Seek Emergency Care

Go to the nearest emergency department or call 911 if you notice any of the following:
  • Rapidly enlarging or ulcerating lesion that bleeds profusely.
  • Severe pain, swelling, or numbness around a known SCC, suggesting infection or perineural invasion.
  • Fever, chills, or red streaks spreading from the site – signs of cellulitis or sepsis.
  • Difficulty breathing, swallowing, or speaking because a tumor on the neck or throat is obstructing the airway.
  • Sudden, unexplained weight loss or new lumps in the neck (possible lymph‑node spread).

Prompt medical attention can prevent life‑threatening complications.

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⚠ Medical Disclaimer

Important: The information provided on this page is for general informational purposes only and is not intended as a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition.

If you think you may have a medical emergency, call your doctor, go to the emergency department, or call 911 immediately.

📚 Medical References