Basal Cell Carcinoma

Overview

Basal cell carcinoma is a common type of skin cancer that starts in the basal cells, which are found in the lower part of the outer layer of the skin. It usually develops on areas that have had long-term sun exposure, such as the face, scalp, ears, neck, shoulders and arms. However, it can occur anywhere on the body.

Basal cell carcinoma typically grows slowly and is often found before it causes serious problems. It rarely spreads to distant parts of the body, but it can grow deeper into nearby skin, tissue, cartilage or bone if left untreated. For this reason, early medical assessment and appropriate treatment are important.

Many people notice a new skin change that does not heal or a spot that looks different from the surrounding skin. Because basal cell carcinoma can look similar to non-cancerous skin conditions, a medical examination is needed to confirm the diagnosis.

Symptoms

Basal cell carcinoma can appear in different ways. It may not be painful, and some people may mistake it for a small sore, scar or irritated patch of skin. Possible signs include:

• A pearly, shiny or translucent bump on the skin
• A pink, red, brown or skin-colored growth
• A flat, scaly patch that may look like eczema or dry skin
• A sore that bleeds, crusts, heals and then returns
• A firm, scar-like area, often pale or waxy in appearance
• A lesion with visible small blood vessels on the surface
• Itching, tenderness or sensitivity in the affected area

On darker skin tones, basal cell carcinoma may appear brown, black or slightly darker than the surrounding skin. Any persistent or changing skin lesion should be checked by a healthcare professional.

Causes and Risk Factors

Basal cell carcinoma develops when the DNA inside basal cells becomes damaged, causing abnormal cell growth. The most important cause is exposure to ultraviolet radiation from the sun or from artificial sources such as tanning devices.

Risk factors may include:

• Frequent or intense sun exposure over many years
• A history of sunburns, especially earlier in life
• Use of tanning beds or similar devices
• Fair skin, light-colored eyes or naturally light hair
• Skin that burns easily or freckles easily
• Older age, although it can occur in younger adults
• A personal or family history of skin cancer
• A weakened immune system
• Previous radiation treatment to the skin
• Long-term exposure to certain environmental substances
• Rare inherited conditions that increase sensitivity to skin cancers

Having one or more risk factors does not mean a person will develop basal cell carcinoma. Likewise, some people develop it without obvious risk factors.

Diagnosis

Diagnosis begins with a medical history and a careful skin examination. The doctor may ask when the lesion first appeared, whether it has changed, bled or failed to heal, and whether there is a history of significant sun exposure or previous skin cancer.

A dermatologist or other trained specialist may examine the lesion with a special magnifying device. If basal cell carcinoma is suspected, a small sample of tissue is usually removed and sent to a laboratory. This is called a biopsy. A pathologist examines the sample under a microscope to confirm whether cancer cells are present and to identify the type of basal cell carcinoma.

In most cases, additional imaging tests are not needed. If the cancer is large, has returned after treatment or appears to involve deeper structures, further assessment may be recommended to understand its extent and plan treatment.

Treatment Options

Treatment depends on the size, depth, location and type of basal cell carcinoma, as well as the patient’s general health and whether the cancer is new or has come back. The goal is to remove or destroy the cancer cells while preserving as much healthy tissue and function as possible.

Common treatment approaches include:

• Surgical removal: The cancer and a small margin of surrounding tissue are removed. The tissue may be examined to ensure the edges are clear.
• Mohs micrographic surgery: Thin layers of skin are removed and examined during the procedure until no cancer cells remain. This may be used for cancers in areas where preserving healthy tissue is especially important, such as the face.
• Scraping and cauterization: The visible tumor is scraped away and the area is treated with heat or another method to destroy remaining cancer cells. This may be suitable for selected superficial lesions.
• Cryotherapy: Extreme cold is used to destroy abnormal tissue in selected cases.
• Radiation therapy: Targeted radiation may be considered when surgery is not suitable or for certain high-risk situations.
• Topical treatments: Some very superficial basal cell carcinomas may be treated with prescription creams applied under medical supervision.
• Light-based treatment: In selected superficial cases, a light-activated treatment may be used after applying a special substance to the skin.
• Systemic therapy: For rare advanced cases, medicines that act throughout the body may be considered by an oncology team.

After treatment, follow-up skin checks are important because people who have had one basal cell carcinoma may develop another skin cancer in the future. Sun protection and regular monitoring of the skin can help reduce risk and support early detection.

When to See a Doctor

Arrange a medical appointment if you notice a skin growth, sore or patch that does not heal, bleeds easily, changes in size, shape or color, or looks different from other spots on your skin. It is also important to seek medical advice if a previously treated area changes or a new lesion appears near a scar.

People with a history of skin cancer, significant sun exposure, weakened immunity or many changing skin lesions should discuss an appropriate skin-check schedule with a healthcare professional. Early evaluation is the safest way to understand a suspicious skin change and choose the most suitable care.