Basal cell carcinoma (BCC)

Basal cell carcinoma (formerly referred to as basal cell epithelioma) is the most common type of skin cancer. It forms in the basal cells of the skin, from which it takes its name.

Description

The areas of the body most frequently affected by basal cell carcinoma are the head and neck (80% of cases), followed by the trunk (15%) and the arms and legs. However, it can occur in other parts of the body, such as the underarms, on the breasts, in the perianal and genital area, and on the palms of the hands and soles of the feet. Generally, the tumor grows very slowly and does not cause metastasis. If left untreated, however, it can infiltrate other tissue and damage them severely. People who have already had basal cell carcinoma are at higher risk of developing others in subsequent years, which will not necessarily appear in the same area of the body as the first tumor.

Causes

The main cause of basal cell carcinoma is excessive exposure to sunlight without proper precautions. Intense and continuous exposure to ultraviolet radiation, either from sunlight or from UV lamps, especially during childhood and adolescence, carries a higher risk of developing basal cell carcinoma.
In rare cases, this skin cancer may arise as a result of physical agents, such as burns, following exposure to radiation from x-rays, or from prolonged contact with chemical agents.
Finally, Gorlin syndrome is a genetic disorder that can cause many basal cell carcinomas to develop.

Symptoms

There are several types of basal cell carcinoma, each of which have different symptoms:

• superficial basal cell carcinoma is the most common form and appears as an erythematous spot with sharp borders;
• nodular basal cell carcinoma is another very common form of basal cell carcinoma. It appears as a pearly lesion with well-defined margins and visible telangiectasias (dilation of small blood vessels). A central crust or ulceration may be present;
• pigmented basal cell carcinoma has both superficial and nodular forms, both of which may have brown, blue, or black lesions due to the presence of pigment;
• scleroderma basal cell epithelioma is the infiltrating form of this carcinoma. Typically, the lesion is scar-like, whitish in color, and is hard to the touch.

Diagnosis

Diagnosis is usually made by observation of the lesion. Sometimes, the dermatologist uses a dermoscopic examination to ascertain that it is basal cell carcinoma.
In cases where there is any doubt on the nature of the lesion, an histologic examination is used.

Treatment

Treatment of basal cell carcinoma is usually local, affecting only the tumor and its immediate vicinity. The goal is to remove the tumor while preserving the function and aesthetic of the area to be treated. Currently, the therapies used are:

• radical surgical removal
• removal by curettage
• photodynamic therapy
• In cases of multiple or advanced tumors the drug vismodegib is used to inhibit tumor growth.

Prevention

Some preventative measures to reduce the risk of basal cell carcinoma occurring include:

• using protective clothing, sunglasses and hats when in the sun; applying a natural, mineral light reflector to any uncovered parts of the body before sun exposure; avoiding sun exposure between 11am and 4pm.
• periodically attending check-ups
• avoiding burning or the use of sunbeds or UV lamps
• regularly examining the entire surface of the body, including the scalp, and notifying a doctor if a new lesion appears; seeking medical attention if a skin lesion:

1. grows
2. forms a scab or bleeds often and remains open for more than three weeks
3. forms a whitish scar-like area
4. changes in size, shape, color or elevation