Treatment of basal cell carcinoma: How is basal cell carcinoma treated?

The goal of treatment is complete removal of the tumour without recurrence.

However, this risk is increased by certain histological features (nature of infiltration, sclerosis, multifocality), centrofacial localization, localization on the auricle and in the capillitium, tumor size above 6 mm and history of previous basalioma.

In order for basalioma to be properly treated, consideration must be given to its:

• histological type
• size
• localization
• previous treatment
• the expected cosmetic outcome

Patient depends on:

• age
• skin phototype
• overall health

The treatment can be divided into:

• surgical (excision, curettage, cauterization,_CO2 laser)
• non-surgical (topical therapy with imiquimod, 5-fluorouracil, cryotherapy, photodynamic therapy and radiotherapy)

Surgical treatment is preferred for circumscribed, non-infiltrating basaliomas. It has the advantage of obtaining a specimen for histopathological examination.

Incomplete excisions (excision) occur in 5-17% of those operated on.

Disadvantages are:

• loss of tissue
• pain
• scarring
• healing time 3-6 weeks
• risk of infection

Most primary BCCs can be easily treated by surgery. The recurrence rate after complete extirpation (removal) is less than 2% to 8% at 5 years after surgery and allows the tissue to be examined histopathologically or by non-surgical methods (cryotherapy, electrocoagulation, PDT, imiquimod treatment..) depending on:

• type
• size
• tumour localisation

BCC with a high risk of recurrence should be treated more aggressively.

The risk of recurrence increases with:

• tumor size
• poorly defined margins
• aggressive histological subtype
• possibly previous tumour recurrence

The aim of surgical treatment is to remove the clinically evident tumour and also its possible microscopic spread to the surrounding area. It is therefore necessary to extirpate (scrape) the tumour with a safety margin.

Subsequently, histopathological examination of formalin-fixed tissue embedded in paraffin is performed.

Current recommendations are 3-4mm safety margin for low-risk tumors (slow growing, less metastatic) and 5-15mm safety margin for high-risk basaliomas (more aggressive, faster growing).

Smaller margins of 2-3mm may be considered in areas where reconstruction options are limited - central face, periorbital, nose, lips, chin, jaw, preauricular and retroauricular areas.

Due to the localization of the basalioma, in 80% of cases it is necessary to proceed with plastic surgery.

Some large lesions require extensive procedures, in which case it is necessary to resort to mutilating procedures (procedures causing mutilation). An example is orbital exenteration (removal of the orbit).

In advanced, mutating stages, we also resort to adjuvant radiotherapy (treatment that enhances the effect of previous treatment) to prevent the spread of the tumour to the surrounding area.

Curettage, electrocoagulation, cryotherapy and laser are methods suitable for small, low-risk basaliomas that are not localized on the face and do not have a multifocal (multilocular) character.

They are essentially an alternative treatment for small, non-risk basaliomas on the trunk and extremities.

They also allow histological examination of the tissue.

Is there a non-surgical treatment for basalioma? Yes, local non-surgical treatment

Cryotherapy is recommended only for small basaliomas, which have a recurrence risk of 7.5 to 16%.

It involves the use of freezing techniques, for example using liquid nitrogen to destroy the tissue at temperatures of -70°C to -196°C.

The duration of application has an impact on the final effect of the therapy.

Disadvantages are:

• the impossibility of histological evaluation
• risk of scarring
• hyperpigmentation

In elderly patients, cryotherapy is a good alternative to surgery.

Radiotherapy (ionizing radiation) is only indicated for inoperable (cannot be surgically removed) and expansive BCCs, for example:

• locally advanced disease
• comorbidity (presence of one or more diseases concurrently with the primary disease)
• refusal of surgery
• in cases where curative surgery is not possible or could be disfiguring or burdened by poor aesthetic outcome (eyelid, nose, lips, large lesions on the ear, forehead or scalp)

Disadvantages are:

• risk of radiodermatitis (inflammation of the skin caused by ionizing radiation).
• alopecia (hair loss)
• secondary skin malignancies (second skin tumours)

Photodynamic therapy (PDT) uses the topical application of a photosensitizer, most commonly aminolevulinic acid or methylaminolevulinate.

The photosensitizer produces oxygen radicals that damage the tumor tissue.

The advantage of this method is its selectivity for tumour tissue. Photodynamic daylight therapy is also useful.

Imiquimod has a dual mechanism, which consists of immunostimulation of both innate and acquired immunity and induction of apoptosis (initiation of programmed death) of cancer cells.

The short-term effect is explained by apoptosis and the long-term effect by immunomodulatory mechanisms. The beneficial therapeutic effect of imiquimod ranges from 82% to 93% of patients.

The combination of treatment options for BCC should be based on the principle of complementary or synergistic (simultaneous) mechanisms of action of the individual treatment modalities.

The combination of different treatment modalities is chosen in patients in whom surgical treatment would have mutating consequences or the expected therapeutic outcome would be unsatisfactory.

Patients may be referred by:

• a dermatovenerologist (a doctor who specialises in skin and genital diseases)
• surgeon
• plastic surgeon
• general practitioner