Basal Cell Carcinoma: CAuses, Symptom and Treatment

Introduction

Basal cell carcinoma (BCC) stands as the most frequent skin cancer, stemming from basal cells located in the skin’s outer layer, the epidermis. These tumors grow slowly, invade locally, and rarely spread to other body areas.

BCC often emerges in sun-exposed skin regions, like the face, neck, and ears, although it can develop anywhere. Despite being the most common skin cancer, BCC generally has a favorable outlook when caught early and managed properly.

BCCs are often wrongly seen as harmless growths due to their slow growth and minimal spreading risk; however, if untreated, they can lead to considerable tissue damage and cosmetic issues.

The high occurrence of BCC makes it a significant public health issue, particularly in groups with high sun exposure. This article discusses the causes, symptoms, risk factors, diagnosis, investigations, and treatment options for basal cell carcinoma.

Causes of Basal Cell Carcinoma

The main cause of basal cell carcinoma is long-term excessive exposure to ultraviolet (UV) radiation from the sun or artificial sources like tanning beds.

UV radiation harms DNA in basal cells, resulting in uncontrolled cell growth and tumor formation.

BCC arises from mutations in genes that regulate cell growth and division. Key factors in the development of BCC include:

1. Ultraviolet Radiation

Sun Exposure: Significant risk for BCC comes from UV exposure, mainly sunlight. UV radiation damages skin cell DNA, especially in basal cells, leading to mutations that can result in cancer.
Tanning Beds: Artificial UV sources, like tanning beds, also heighten BCC risk, especially in younger people who often use them.

2. Genetic Mutations

PTCH1 Gene Mutation: The PTCH1 gene mutation is crucial for BCC development as it disrupts normal cell growth and division regulation, causing uncontrolled basal cell proliferation.
Other Genetic Factors: A family history of skin cancer or genetic conditions like Gorlin syndrome may make some individuals more likely to develop multiple basal cell carcinomas at a young age.

3. Environmental Factors

Chronic Skin Damage: Ongoing skin injuries or scars may raise BCC risk. Damaged areas may lead to irregular cell growth as they heal.
Chemical Exposure: Long-term contact with specific chemicals, such as arsenic, may raise skin cancer risks, including BCC.

4. Immune System Weakness

Immunocompromised Individuals: Those with weakened immune systems, such as organ transplant recipients or people with HIV/AIDS, face a higher risk for BCC. Immunosuppressive treatments can diminish the body’s ability to manage abnormal cell growth.

5. Age and Gender

BCC is often seen in individuals over 50 due to the accumulation of UV-induced skin damage over the years.

However, it can occur in those younger, particularly with a history of significant sun exposure.

Men are more frequently diagnosed with BCC than women, although cases in women are on the rise, especially among younger age groups.

Symptoms of Basal Cell Carcinoma

Basal cell carcinoma typically shows as a harmless, slowly developing growth or lesion on the skin. It is often located in sun-exposed regions like the face, neck, ears, and hands.

Typical symptoms and traits of BCC include:

• Pearly or Waxy Look: Basal cell carcinoma (BCC) often looks like a shiny, pearly, or waxy bump. The tumor might have a slightly raised surface that can be seen with small blood vessels (telangiectasia).
• Ulcerated or Crusted Areas: As BCC grows, it may become ulcerated and form a crater in the center. The lesion may bleed, crust, and then heal, but it can come back in the same spot.
• Flat or Scaly Patches: Sometimes, BCC shows up as a flat, scaly, reddish area or a sore that does not heal. This can be confused with eczema or a long-lasting rash.
• Itching or Tenderness: While BCCs are mostly painless, they can sometimes itch or feel tender. These feelings can happen more when the tumor increases in size or gets open sores.
• Bleeding or Scabbing: BCC lesions can bleed easily, especially if they get rubbed, scratched, or hurt lightly. Ongoing scabbing or a wound that won’t heal might also suggest BCC.
• Slow Growth: BCCs usually grow slowly over many months or years. The tumor size can vary from a small, hard-to-see bump to a large, ulcerated growth.

Risk Factors for Basal Cell Carcinoma

Some factors make it more likely to get basal cell carcinoma:

• Light Skin: People with fair skin, light hair, and light eyes are more at risk for BCC because they have less melanin, which offers some defense against UV rays.
• History of Sunburns: Past severe sunburns, especially in childhood or teenage years, raise the chances of developing BCC later. Sunburns damage skin cell DNA, and repeated UV exposure builds up damage over time.
• Many Moles or Freckles: Having many moles or freckles increases skin cancer risk, including BCC, as these marks may show higher vulnerability to UV skin damage.
• Family History of Skin Cancer: A family history of basal cell carcinoma or similar skin cancers raises the risk. Genetic mutations, like those in Gorlin syndrome, also contribute to family BCC cases.
• UV Exposure: Continuous, high sun exposure or using tanning beds greatly boosts the risk of developing BCC.
• Past Skin Cancer: People who have previously had basal cell carcinoma or other skin cancers have a greater chance of developing more skin cancers.

Differential Diagnosis

Basal cell carcinoma may be confused with various other skin conditions. The differential diagnosis involves:

• Squamous Cell Carcinoma (SCC): SCC is another form of skin cancer that often looks like a firm, raised, red nodule with a scaly surface. SCC is usually more aggressive than BCC and tends to spread more.
• Actinic Keratosis: This precancerous skin lesion often appears as a dry, scaly spot on sun-damaged skin. Actinic keratosis can sometimes progress to SCC but is less likely to turn into BCC.
• Melanoma: The most dangerous type of skin cancer, melanoma can sometimes be mistaken for BCC. Melanomas typically have irregular edges, multiple colors, and an asymmetrical shape. They have a higher chance of spreading than BCC.
• Seborrheic Keratosis: This is a non-cancerous growth that often looks like a brown, wart-like bump. It usually appears more raised and seems more “stuck-on” compared to BCC.
• Benign Cysts: Various non-cancerous cysts, like epidermoid or pilar cysts, can look like lumps on the skin and might be mistaken for BCC. These cysts typically can be moved and have a smooth surface.
• Pyogenic Granuloma: A benign vascular lesion that can resemble BCC. Pyogenic granulomas are often red or purple and can bleed easily.

Investigation

To diagnose basal cell carcinoma, a clinical examination followed by some tests is usually required. Main methods of diagnosis include:

• Physical Examination: A complete skin check is the initial step in diagnosing BCC. BCC. The healthcare provider will look at the lesion’s look, where it is, how big it is, and if there are any signs like bleeding or sores.
• Dermatoscopy: Dermatoscopy is a method that looks closely at the skin lesion using a handheld device that lights it up and magnifies it. This can help to tell BCC apart from other skin issues.
• Skin Biopsy: A skin biopsy is the main test to diagnose BCC. The usual way is an excisional biopsy, where a piece of tissue from the lesion is taken out and looked at under a microscope. This helps the pathologist to verify the diagnosis and find out what type of tumor it is.
• Molecular Testing: Sometimes, molecular tests may be done on the tumor tissue to find specific changes like PTCH1 mutations, which may help with treatment choices.
• Imaging Studies: For bigger BCCs or those thought to spread locally, imaging tests like a CT scan or MRI might be used to see how far the tumor has spread and help in planning treatment.

Treatment of Basal Cell Carcinoma

Treatment for basal cell carcinoma depends on how big, where, and what kind of tumor it is, along with the patient’s overall health. Treatment choices include:

• Surgical Excision: The typical treatment for BCC is surgical excision, which means the tumor is cut out along with some normal tissue around it to ensure it is fully removed. This method works very well for small, local tumors.
• Mohs Micrographic Surgery: Mohs surgery is a special method that takes off the tumor layer by layer, checking each layer under a microscope to make sure all cancer cells are gone. This is especially good for tumors in areas where appearance matters, like the face.
• Cryotherapy: Cryotherapy uses liquid nitrogen to freeze the tumor, killing the cancer cells. This is often used for small, surface-level BCCs.
• Topical Treatments: Some topical drugs like imiquimod or 5-fluorouracil (5-FU) can be used for surface BCCs. These drugs help the immune system or directly harm the tumor cells.
• Radiation Therapy: Radiation may be used for tumors hard to take out surgically, for those not able to have surgery, or for returning BCCs. It uses powerful rays to kill cancer cells.
• Photodynamic Therapy (PDT): PDT means putting a special agent on the skin and then shining light on it, activating it to kill cancer cells. PDT works best for surface BCCs.
• Targeted Therapy: For advanced or returning BCCs, especially those tied to basal cell nevus syndrome, treatments like hedgehog pathway inhibitors (such as vismodegib) may be used. These target certain pathways involved in tumor growth.
• Chemotherapy: Chemotherapy is not often used for BCC since it usually grows slowly, but it may be an option for serious, inoperable tumors or cases that have spread.

Conclusion

Basal cell carcinoma is a common and usually treatable skin cancer, with a high success rate when caught early. The main risk for BCC is long-term exposure to the sun, though genetic factors and some environmental exposures also matter.

Symptoms of BCC can differ by location, but they often show as a shiny, raised lesion that might bleed or break open.

Diagnosis is confirmed through examination and biopsy, and treatment options vary from surgical removal to radiation and topical treatments.

Acting early is crucial to avoid problems and to improve outcomes for patients with basal cell carcinoma.