There are three main types of skin cancer – basal cell, squamous cell and malignant melanoma.
This is by far the most common and least problematic form of skin cancer. It makes up more cases than all the other cancers put together. If left untreated it is likely to damage the flesh around it and to enlarge. However, it is usually slow growing and typically does not spread to other parts of the body.
Treatment for a basal cell carcinoma is generally surgery. The lesion is excised with a margin of 4 mm of normal skin around it and the defect is then repaired.
Moh’s micrographic surgery is the preferred option for basal cell carcinomas on the face because it does not require a margin to be removed around the excision site and can offer an optimal cosmetic result. The cancer is removed one layer at a time and then sent for microscopic examination.
Patients remain on the unit whilst this is taking place and, if incomplete removal is demonstrated, further layers are taken away until no abnormal cells remain. Radiotherapy can also be used for basal cell lesions, depending on their size and location.
This is the second most common type of skin cancer. This does have the potential to spread and metastasize but it rarely does. If it were to spread, this would normally be to the lymph glands. In such cases plastic surgeons can perform a procedure called a lymph node dissection.
Treatment for squamous cell lesions is normally surgical excision, with a 5 mm margin of normal skin. Moh’s surgery would only be the treatment of choice for this type of cancer if it were in a delicate location, such as an eyelid, where as much tissue as possible needed to be preserved.
Melanoma is the most aggressive form of skin cancer. It presents in a number of forms, some of which – such as lentigo maligna and melanoma in situ – occupy the top layer of skin and are not in danger of migrating. Normally, however, melanomas are considered to have the potential to spread and are treated urgently.
Treatment consists in taking an excisional biopsy, which involves removing the suspicious area with a margin of 2 mm of normal skin. If histology confirms the diagnosis, a wide local excision is performed to reduce the risk of local recurrence.
Even where melanomas have metastasized, there have been recent advances in treatments from our colleagues in plastic surgery and oncology that are offering a better prognosis for patients within this group.