Basal cell carcinoma

Medical quality assurance by Dr. Albrecht Nonnenmacher, MD at February 10, 2016
StartDiseasesBasal cell carcinoma

Basal cell carcinoma is the most common type of skin cancer. Though it most often grows slowly and rarely spreads, basal cell carcinoma can be disfiguring and can destroy nerve cells and muscle cells. Basal cell carcinoma, or BCC is almost always curable if detected early.

Contents

Definition & Facts

Basal cell carcinomas arise from the basal cells in the skin. These cells make up the deepest layers of the epidermis, which is the top layer of skin. When they become malignant, basal cells begin to proliferate in ways that are abnormal. There were nearly 3 million diagnoses of BCC in 2010, and medical experts believe that the number is growing as the population ages.

Symptoms & Complaints

BCC often manifests as an open sore that refuses to heal permanently. Over a timespan of weeks, the sore oozes fluid or bleeds, crusts over but opens up again.

BCC can also show up as a reddish patch. The patch might itch and cause pain or may be painless. Like the oozing sore, it may also crust over. These malignant patches are found most often on the patient's arms, legs, shoulders, chest or face. Again, they do not go away on their own.

Basal cell carcinoma can also appear as a bump or nodule. These nodules or bumps are shiny and even pearlescent and can come in a variety of colors. Darker colored nodules may prove problematic for dark-skinned people, because the lesions resemble normal moles.

A classic sign of a BCC is a pink lesion with a border that is elevated and rolled. There may be an ulcer or crusted over area in the center. As the lesion grows, larger blood vessels start to appear on top of it. BCC can also mimic a tight scar with a waxy sheen. This is a sign that the cancer is actually larger than it appears and has become invasive. Often, more than one of these signs appears in a basal cell carcinoma.

Causes

The main cause of basal cell carcinoma is sun damage. This damage is caused by the ultraviolet radiation exposure given off by the sun. The malignancy is most often seen in those parts of the body that get a lot of sun exposure, although it is possible for lesions to develop in places that aren't exposed to the sun.

Other things that may contribute to the development of basal cell carcinoma are wounds in the skin that don't heal, arsenic exposure and radiation. BCC can also be a complication of infections, burns and other injuries to the skin. This can even include tattoos. Researchers have come to suspect these possible risk factors because BCC sometimes strikes young people or appears in places not exposed to sunlight.

Though anyone can get BCC, people most at risk are fair-skinned, with red or blond hair and light eyes. Men are more at risk for BCC than women, and the tendency to contract some types of BCC is inherited. Having one bout of basal cell carcinoma also puts a person at risk for having another later on, so it is important that a person who has had BCC see their dermatologist regularly.

Diagnosis & Tests

In order to make a diagnosis of BCC, a dermatologist examines the patient's skin. If they see a suspicious lesion, they will take a skin biopsy. There are several types of skin biopsy. All of them begin with the area being cleaned with alcohol and numbed with a local anesthetic.

A punch biopsy uses a small tool that looks like a cookie cutter. It is placed over the lesion, pushed down and twisted to remove a bit of skin. The skin is then lifted up with forceps, snipped and placed in a container. The patient may need stitches after this procedure.

In a shave biopsy, the doctor uses a scalpel to shave off layers of skin. Stitches aren't needed with this procedure unless the area is fairly large. With excision biopsy, the entire lesion is cut out and prepared for the lab. The surgical wound is closed with stitches. The sample is then placed in formaldehyde in a small container and sent to a lab for testing.

Treatment & Therapy

Treatment and therapy for BCC depends on where it is, what type it is and how extensive it is. Among the treatments are:

  • Surgical Excision. The lesion is removed along with a margin of healthy tissue. This procedure is used with large basal cell carcinomas.
  • Cryosurgery. In this procedure, the cancer cells are destroyed by the application of liquid nitrogen. This treatment is good for a cancer that has not penetrated into the skin.
  • Electrodesiccation and curettage. With electrodesiccation and curettage, or ED & C, the surgeon removes the cancer with a curette and then uses an electric needle to burn what's left. This procedure is used when the cancer is small.
  • Mohs Surgery. In this surgery, the surgeon removes the cancer one layer at a time, checks the layers beneath a microscope and keeps removing them until no more cancer cells are found. Mohs surgery prevents too much healthy tissue from being removed. It is especially effective on large and aggressive BCCs.
  • Chemotherapy. Those rare basal cell carcinomas that have spread to other organs are treated with chemotherapy drugs such as vismodegib.

Prevention & Prophylaxis

Researchers believe that the best way to prevent basal cell carcinoma is to cover up and/or wear sunscreen when going outdoors. Sunscreen needs to be worn every day and needs to be worn even during cloudy days, for ultraviolet rays can penetrate cloud cover. The best sunscreen protects against both ultraviolet A and ultraviolet B radiation.

The patient must also avoid tanning beds, which damage the skin much like the sun, and should also become familiar with their skin. This helps them to notice any changes.