Basal Cell Carcinoma

1 What is Basal Cell Carcinoma?

Basal cell carcinoma (BCC) is a cancerous lesion of the skin.

BCC occurs when there is an abnormal, uncontrollable growth of basal cells, which form the deepest layer in the epidermis of the skin.

The basal cells of the skin normally produce new skin cells as the older cells die.

BCC usually appears as a waxy bump, though it may appear in other forms such as red patches, ping growths, open sores or scars.

This lesion often occurs on the face or neck when continuously exposed to ultraviolet (UV) radiation from intense sunlight.

BCC does not spread beyond the primary site, except in very rare cases.

2 Symptoms

The symptoms of basal cell carcinoma may include a bump or growth on the skin that appears:

  • Pearly white or waxy, often with visible blood vessels, on your face, ears or neck. These bumps bleed and form a crust. In people with darker complexion, this type of cancer may appear brown or black.
  • Flat, scaly, red, brown or flesh-colored patch on your back or chest. Over time, these skin patches can become very large.
  • White or pinkish waxy scar. This type of basal cell carcinoma is a sign of a particularly invasive and disfiguring cancer called morpheaform basal cell carcinoma.

Other signs include:

  • A skin sore with oozing or crusting spots
  • A sore that appears like a scar without having an injury in the area
  • Irregular blood vessels around the sore
  • A sore with a central depression or sunken area

Basal cell carcinomas develop gradually on the most sun-exposed parts of your body such as your face, head, and neck.

In some cases, it may occur on the torso and legs. The lesion does not cause pain.

A general warning sign of skin cancer is a sore that does not heal or bleeds repeatedly and scabs over.

3 Causes

Basal cell carcinoma starts developing when one of the basal cells in the skin's epidermis undergoes a mutation in its DNA.

The process of forming new skin cells is controlled by the DNA of a basal cell, but mutated DNA results in rapid, uncontrollable multiplication of basal cells, and continuous growth without cell death.

Over a period of time, the abnormal cells accumulate to form a cancerous mass.

Ultraviolet light and other causes

Most of the damage to the DNA in basal cells occur as a result of regular exposure to sunlight or other ultraviolet (UV) radiation found in commercial tanning lamps and tanning beds.

However, in rare cases, skin cancers can also develop on areas unexposed to sunlight.

This suggests that there are other contributing factors to the risk of skin cancer, such as being exposed to toxic substances like arsenic, having a chronic inflammatory skin condition, and complications of burns, scars, vaccinations, or even tattoos.

4 Making a Diagnosis

In order to diagnose basal cell carcinoma, your doctor may perform the following tests:

  • Examination of your skin: Your doctor will carefully examine the suspicious area of your skin. Also, the remaining parts of your body are examined to check for unusual skin characteristics.
  • Removal of a sample of skin for testing: Your doctor will perform a skin biopsy, which involves removal of a small portion of the unusual skin for microscopic examination in a laboratory. This reveals the type of your skin cancer.

If you have a skin sore or a lesion that concerns you, consult your primary care doctor.

Make a list of the following:

  • Your past medical history, including the conditions for which you have undergone treatment. Also, include radiation therapy you may have received.
  • History of exposure to intense UV light, including sunlight or tanning beds. For example, inform your doctor if you were working as an outdoor lifeguard or spent lot of time at the beach.
  • Your family members who have had skin cancer.
  • Your regular medications and natural remedies. Include prescriptions as well as over-the-counter medications you are taking.

Make a list of questions you want to ask your doctor in advance.

Ask a family member or a friend to accompany you during your appointment.

Even though skin cancer can be treated, just hearing the word "cancer" can make it difficult for you to concentrate on what the doctor suggests.

Below are few basic questions that can be asked to your doctor about basal cell carcinoma.

  • Which type of skin cancer do I have?
  • How does this type of skin cancer differ from other types?
  • Has my cancer spread to other sites?
  • What is the treatment approach recommended for my cancer?
  • Are there any side effects of this treatment?
  • Will a scar remain after treatment?
  • Am I at risk of this condition recurring?
  • Am I at risk of other types of skin cancer?
  • How often will the follow-up visits be scheduled after finishing the treatment?
  • Will my family members be at a high risk of skin cancer?

Your doctor may ask you a number of questions that include:

  • When was your skin growth or lesion noticed first?
  • Has it grown significantly since you first saw it?
  • Is there any pain associated with the growth or lesion?
  • Have you developed other growths or lesions of concern?
  • Did you develop any skin cancer in the past?
  • Does anyone in your family have skin cancer? What kind?
  • Were you regularly exposed to the sun or tanning beds as a child and teenager?
  • Are you exposed to the sun or tanning beds now?
  • Are you currently on any medications including herbal remedies?
  • Have you been subjected to radiation therapy for any medical condition?
  • Have you been on medications that suppress your immune system?
  • Have you been treated for any significant medical conditions before?
  • Do you have the habit of smoking?
  • Are you exposed to pesticides or herbicides at your workplace?
  • Do you depend on well water as your primary source of water?
  • Do you take precautions to protect yourself from the sun, such as avoiding midday sun and using sunscreen?
  • Do you perform self examination of your skin on a regular basis?

In order to diagnose basal cell carcinoma, your doctor may perform the following tests:

  • Examination of your skin: Your doctor will carefully examine the suspicious area of your skin. Also, the remaining parts of your body are examined to check for unusual skin characteristics.
  • Removal of a sample of skin for testing: Your doctor will perform a skin biopsy, which involves removal of a small portion of the unusual skin for microscopic examination in a laboratory. This reveals the type of your skin cancer.

5 Treatment

Several treatments are available for basal cell carcinoma.

The treatment that is best for you is decided based on the size, depth, location and severity of your skin cancer as well as your general health.  

Some commonly used basal cell carcinoma treatments include:

  • Electrodesiccation and curettage (ED&C): ED&C involves removal of the skin cancer cells from the surface with a scraping instrument (curette) and then searing the base of the cancer with an electrocautery needle. This treatment is often used in cancers that are not very deep, often located on the legs and ears. ED&C may leave behind an oozing, crusty scab that heals in a few weeks.
  • Surgical Excision: In this procedure, the cancerous tissue is excised, sometimes, along with a margin of healthy skin. A wide excision involves removal of additional normal skin around the cancer. This is an option in large BCC. Skin reconstruction may be performed at a later stage to minimize scarring, especially on your face.
  • Cryosurgery or Freezing: This involves killing the cancerous cells by freezing them with the use of liquid nitrogen. It is an option for treatment of superficial cancers that are not very large.
  • Mohs Micrographic Surgery: During this procedure, your doctor will remove each layer of cancer cells, and examine it under a microscope until there are no abnormal cells evident during the microscopic exam. This ensures that the entire growth is being removed without excising an excess amount of surrounding healthy tissue. This is the treatment of choice for recurrent basal cell carcinomas that are large, deep, fast-growing, morpheaform or on your face.
  • Topical treatments: Superficial BCC that does not involve deeper layers of the skin may be treated with skin creams or ointments. Medications such as imiquimod (Aldara) and fluorouracil (Carac, Fluoroplex, Efudex) are prescribed for several weeks to treat certain superficial basal cell carcinomas.
  • Medication for advanced cancer: Basal cell carcinoma that has spread to other sites of the body (metastasis) may be treated with vismodegib (Erivedge). This medication may also be prescribed in patients in whom other treatments have failed.
  • Photodynamic therapy: This involves treatment of cancers that are not very large or deep using light.
  • Radiation therapy: X-ray beams will be directed to the site of BCC, with no need for cutting or anesthesia. This is considered if a basal cell cancer cannot be treated with surgery.

6 Prevention

You can follow precautionary measures to prevent basal cell carcinoma:

  • Avoid exposure to the midday sun: Keep away from the sun when its rays are very intense (between about 10 a.m. and 4 p.m in most places). Try to schedule your outdoor activities at other times of the day, even in the winter. You can absorb harmful UV radiation all throughout the year as clouds may not protect from the damaging rays of the sun.
  • Apply a sunscreen lotion year-round: Choose a sunscreen that can block both UVA and UVB types of radiation from the sun. Apply sunscreen generously on all exposed parts of your body, including your ears and feet. Reapply the sunscreen every two hours or even more frequently if you're swimming or perspiring. Use a water-resistant sunscreen and apply the lotion at least about half-an-hour before going outdoors. The American Academy of Dermatology recommends use of a broad-spectrum sunscreen with a SPF of 30 or more. Apply your sunscreen lotion even during winters and cloudy days.
  • Wear protective clothing: Sunscreens alone cannot protect your skin from UV rays completely. Therefore, wearing closely woven clothing that covers your arms and legs, a broad-brimmed hat, and UV-blocking sunglasses is important. Choose a pair of glasses that provides protection from both UVA and UVB rays.
  • Avoid tanning beds: Tanning beds emit UV radiation, which can increase your risk of developing skin cancer. Spending only about 15-20 minutes at a tanning bed can be as dangerous as an entire day spent under the sun.
  • Examine your skin head-to-toe at least once a month: Become familiar with your skin so that you can quickly note if any changes occur. If you notice anything abnormal, inform your doctor during the next appointment.

If you already have skin cancer, you will be at an increased risk of developing a second cancer.

Discuss with your dermatologist how often you should be screened for a recurrence and the ways by which you can perform periodic skin checks on your own.

7 Risks and Complications

Any individual with a history of long-term exposure to sun may develop Basal cell carcinoma, however, factors that increase your risk of having BCC include:

  • Chronic sun exposure: Extended hours spent under the sun or in commercial tanning booths can increase your risk of developing BCC. The risk is more if you reside at sunny places or at high-altitudes, both of which make you exposed to higher amounts of UV radiation. The risk is also greater if you have had excessive sun exposure before the age of 18.
  • Exposure to radiation: Psoralen plus ultraviolet A (PUVA) radiation used to treat psoriasis may increase your risk of developing BCC and other forms of skin cancer. Radiation treatments for childhood acne or other conditions also may enhance your risk of basal cell carcinoma.
  • Fair skin: If you have a very fair complexion, sunburn may result very easily, and you are more likely to develop BCC than people with a darker complexion.
  • Your sex: Men are more likely to develop BCC than women.
  • Your age: BCC is most common in people above 50 years of age.
  • A past or family history of skin cancer: You may develop BCC again, if you have had the cancer one or more times in the past. Also, a family history of skin cancer may make you more susceptible to the risk of developing basal cell carcinoma.
  • Immune-suppressing drugs: Being on medications that suppress your immune system, particularly after organ transplantation can increase your risk of skin cancer. Cancers that develop in people with a weak immune system are more aggressive than while they occur in otherwise healthy people.
  • Exposure to arsenic: Arsenic is a harmful metal that is found widely in the environment such as in the soil, air, and underground water. Arsenic exposure is common, and it increases the risk of BCC and other cancers. Farmers, refinery workers, and people who drink contaminated well water or reside near smelting plants are exposed to higher levels of arsenic.
  • Inherited syndromes: Few rare genetic diseases may increase the risk of BCC. For example, nevoid basal cell carcinoma syndrome (Gorlin-Goltz syndrome) causes numerous BCCs along with symptoms such as pitting on the hands and feet and spine abnormalities.

Complications of BCC can include:

  • Recurrence: Recurrence of BCC is very common even after successful treatment, and often happens at the same site.
  • An increased risk of developing other skin cancers: A history of BCC may also increase your chance of developing other types of skin cancer such as squamous cell carcinoma and melanoma.
  • Cancer that spreads to other organs: Rarely, aggressive forms of BCC can spread to involve and destroy neighboring muscles, nerves and bones. In extremely rare cases, BCC may metastasize to other parts of the body.

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