Usually, a small, shiny bump appears on the skin and enlarges slowly.
The bumps may break open and form a scab, sometimes with bleeding, or become flat, resembling a scar.
This cancer can often be identified by sight, but doctors usually do a biopsy.
The cancer is usually removed, but sometimes people may be given chemotherapy drugs applied to the skin, immunotherapy, or, occasionally, radiation therapy or medications taken by mouth.
Basal cells are in the lowest layer of the epidermis (the outer layer of the skin). Although basal cell carcinoma may not develop from the basal cells, the disease is so named because the cancer cells look like basal cells under a microscope.
Basal cell carcinoma is the most common type of skin cancer Overview of Skin Cancer Skin cancer is the most common type of cancer, and people of all skin tones can be affected. People who have light skin are particularly susceptible to developing most forms of skin cancer because... read more . Approximately 2 million people develop this type of cancer in the United States each year.
Basal cell carcinoma is most common among people who have light skin and a history of sun exposure. It is very rare among people with dark skin.
Basal cell carcinoma usually develops on skin surfaces that are exposed to sunlight, commonly on the head or neck, and may develop in a type of birthmark that often appears on the scalp (nevus sebaceus). Basal cell carcinoma also may develop in people who have certain hereditary disorders, such as xeroderma pigmentosum, Gorlin syndrome, and Bazex syndrome.
The tumors enlarge very slowly, sometimes so slowly that they go unnoticed as new growths. However, the growth rate varies greatly from tumor to tumor, with some growing as much as ½ inch (about 1 centimeter) in a year.
Basal cell carcinomas rarely spread (metastasize) to other parts of the body. Instead, they invade and slowly destroy surrounding tissues. When basal cell carcinomas grow near the eyes, ears, mouth, bone, or brain, the consequences of spread can be serious and can lead to death. Yet, for most people, the tumors simply grow slowly into the skin.
Symptoms of Basal Cell Carcinoma
There are several types of basal cell carcinomas.
The nodular type of basal cell carcinoma usually begins as small, shiny, firm, almost clear to pink in color, raised growth. After a few months or years, visible dilated blood vessels (telangiectases) may appear on the surface, and the center may break open and form a scab. The border of the cancer is sometimes thickened and pearly white. The cancer may alternately bleed and form a scab and heal, leading a person to falsely think that it is a sore rather than a cancer.
Other types of basal cell carcinomas vary greatly in appearance. For example, the superficial type appears as flat, thin, red or pink patches, and the morpheaform type appears as thicker flesh-colored or light red patches that look somewhat like scars.
Diagnosis of Basal Cell Carcinoma
Doctors often can recognize a basal cell carcinoma simply by looking at it, but a biopsy Biopsy Doctors can identify many skin disorders simply by looking at the skin. A full skin examination includes examination of the scalp, nails, and mucous membranes. Sometimes the doctor uses a hand-held... read more is the standard procedure for confirming the diagnosis. During this procedure, doctors remove a piece of the tumor and examine it under a microscope.
Treatment of Basal Cell Carcinoma
Removal of the tumor (many different methods)
Basal cell carcinomas should be treated by a specialist.
Doctors may remove the cancer in the office by scraping and burning it with an electric needle (a procedure called curettage and electrodesiccation) or by cutting it out. Doctors may destroy the cancer by using extreme cold (cryosurgery).
Certain chemotherapy drugs Chemotherapy and Other Systemic Cancer Treatments Systemic treatments are those that have effects throughout the body rather than being applied directly to the cancer. Chemotherapy is a form of systemic treatment that uses drugs to kill cancer... read more may be applied to the skin. Photodynamic therapy (see Using Lasers to Treat Skin Problems Using Lasers to Treat Skin Problems ), in which chemicals and a laser are applied to the skin, also may be used. Occasionally, radiation therapy Radiation Therapy for Cancer Radiation is a form of intense energy generated by a radioactive substance, such as cobalt, or by specialized equipment, such as an atomic particle (linear) accelerator. Radiation preferentially... read more is used.
A technique called Mohs microscopically controlled surgery Mohs Microscopically Controlled Surgery may be required for some basal cell carcinomas that are large or regrow or occur in certain areas, such as around the nose and eyes.
People whose cancer has spread to nearby tissues or spread to other parts of the body (metastasized) and who are not candidates for surgery or radiation therapy may be given the medication vismodegib or sonidegib by mouth. People who cannot take vismodegib or sonidegib may be given a type of immunotherapy Monoclonal antibodies Immunotherapy is used to stimulate the body's immune system against cancer. These treatments target specific genetic characteristics of the tumor cells. The genetic characteristics of tumors... read more called cemiplimab.
Prognosis for Basal Cell Carcinoma
Treatment of basal cell carcinoma is nearly always successful, and the cancer is rarely fatal. However, almost 25% of people who have had 1 basal cell carcinoma develop a new basal cell cancer within 5 years of the first one. Thus, anyone with one basal cell carcinoma should have a yearly skin examination.
Prevention of Basal Cell Carcinoma
Because basal cell carcinoma is often caused by sun exposure, people can help prevent this cancer by doing the following, starting in early childhood:
Avoiding the sun Avoidance Sunburn results from a brief (acute) overexposure to ultraviolet (UV) light. Overexposure to ultraviolet light causes sunburn. Sunburn causes painful reddened skin and sometimes blisters, fever... read more : For example, seeking shade, minimizing outdoor activities between 10 AM and 4 PM (when the sun’s rays are strongest), and avoiding sunbathing and the use of tanning beds
Wearing protective clothing Clothing Sunburn results from a brief (acute) overexposure to ultraviolet (UV) light. Overexposure to ultraviolet light causes sunburn. Sunburn causes painful reddened skin and sometimes blisters, fever... read more : For example, long-sleeved shirts, pants, and broad-brimmed hats
Using sunscreen Sunscreens Sunburn results from a brief (acute) overexposure to ultraviolet (UV) light. Overexposure to ultraviolet light causes sunburn. Sunburn causes painful reddened skin and sometimes blisters, fever... read more : At least sun protection factor (SPF) 30 with UVA and UVB protection used as directed and reapplied every 2 hours and after swimming or sweating but not used to prolong sun exposure
In addition, any skin change that lasts for more than a few weeks should be evaluated by a doctor.
The following English-language resources may be useful. Please note that THE MANUAL is not responsible for the content of these resources.
American Cancer Society: Basal and Squamous Cell Skin Cancer: Information about skin cancers , including detection, prevention, treatment options, and other resources
The Skin Cancer Foundation: Basal Cell Carcinoma Overview: Information about basal cell carcinoma, including detection, prevention, treatment options, and other resources