Basal cell carcinoma (BCC) is the most common skin cancer. It develops from basal cells in the lower layer of the skin, usually on sun-exposed areas, and often appears as a shiny bump or a sore that does not heal. It grows slowly and rarely spreads, but can cause local tissue damage if untreated.
Basal cell carcinoma is a form of non-melanoma skin cancer. It arises when basal cells undergo abnormal genetic changes that cause them to multiply uncontrollably. Instead of dying and being replaced as part of the normal skin renewal process, damaged cells accumulate and form a tumour.
Although BCC is considered less aggressive than some other skin cancers, it is still a malignant condition. Over time, untreated lesions may enlarge and damage nearby skin, cartilage or bone, particularly on the face and head.
Basal cell carcinoma is the most frequently diagnosed skin cancer worldwide. It accounts for the majority of non-melanoma skin cancers. Many cases are treated in primary or outpatient settings and may not always be recorded in national cancer registries, meaning the true incidence is likely higher than reported figures suggest.
Basal cell carcinoma can occur at any age, but risk increases with cumulative UV exposure over time. Factors associated with a higher likelihood of developing BCC include:
People with darker skin tones can also develop BCC, although it is less common and may be detected later.
BCC most often appears on areas of skin that receive frequent sun exposure, including the face, nose, ears, scalp, neck and shoulders. It can also develop on less exposed areas of the body, which is why full skin examinations are important.
Basal cell carcinoma is usually not life-threatening. However, it should not be ignored. Without treatment, lesions can grow larger and cause destruction of surrounding tissue. Early diagnosis allows for simpler treatment and better cosmetic and functional outcomes.
Basal cell carcinoma can appear in several forms and may look different from person to person. Common appearances include:
Symptoms often develop slowly and may not cause pain, which can delay medical assessment.
The primary cause of basal cell carcinoma is DNA damage within basal cells. This damage is most often caused by ultraviolet radiation from sunlight. UV radiation interferes with normal DNA repair mechanisms, allowing abnormal cells to survive and multiply.
Artificial sources of UV radiation, such as sunbeds and tanning lamps, also increase the risk. Over time, repeated exposure allows DNA damage to accumulate, increasing the likelihood of cancer development.
Yes. Although uncommon, BCC can develop in areas with little sun exposure. In these cases, genetic factors, immune suppression or previous radiation exposure may contribute.
Diagnosis begins with a clinical skin examination. A healthcare professional assesses the lesion’s size, shape, colour, texture and borders, as well as its duration and any changes over time. The surrounding skin is also examined for additional lesions.
Most cases of basal cell carcinoma do not require further testing beyond biopsy. Imaging tests may be considered if there is concern about deeper tissue involvement, which is uncommon.
Treatment aims to remove or destroy the cancer while preserving healthy tissue. The choice of treatment depends on factors such as tumour size, depth, location, subtype and the individual’s overall health.
Treatment options may include:
Your healthcare professional will explain the benefits and risks of each option.
Yes. Basal cell carcinoma can recur at the same site or develop elsewhere on the skin. People who have had BCC are at increased risk of future skin cancers and usually benefit from regular skin monitoring.
The outlook for basal cell carcinoma is generally very good, particularly when it is diagnosed and treated early. Most cases are successfully managed with local treatment. Untreated lesions, however, can grow and cause significant local damage.
Ongoing skin checks may be recommended, especially for individuals with a history of multiple lesions or previous skin cancer.
Basal cell carcinoma cannot always be prevented, but the risk can be lowered by protecting the skin from ultraviolet (UV) radiation. Helpful steps include avoiding prolonged sun exposure during the middle of the day, using a broad-spectrum sunscreen with an SPF of 30 or higher, and wearing protective clothing such as long sleeves and wide-brimmed hats.
Sunbeds and artificial tanning should be avoided, as they increase UV exposure. Checking your skin regularly for new or changing marks and seeking medical advice if changes occur can help with early detection.
If something on your skin does not look or feel right, arranging a review can help detect problems early and support effective care.
