Facts and figures about non-malignant melanoma skin cancer
Non malignant melanoma skin cancers arise in the upper layers of the skin and are extremely common, 74% of these are basal cell carcinomas (sometimes referred to as rodent ulcers), 23% are squamous cell carcinomas and the other 3% are a mixed group of rare skin cancers.
They are more than 102,000 new cases registered each year in the UK, but exact numbers are difficult to assess as it is estimated that approximately 30-50% of basal cell carcinomas (BCC) and 30% of squamous cell carcinomas (SCC) are not entered onto the cancer register.
Higher incidence in men, male to female ratio is 13:10. Age related, incidence rises from 40 years of age and peaks in the 70+ age group.
They commonly appear on areas exposed to the sun, mainly on the face, neck, bald scalp, arms, back of hands and lower legs. Risk of spread from these tumours is only 0.5% for BCC and 2-5% for SCC. Approximately 90% are successfully cured.
Risk factors are sun exposure and sunbeds (ultra violet radiation) particularly in Caucasians, estimated that 50-90% of basal cell carcinomas and 50-70% of squamous cell carcinomas are linked to UV radiation, outdoor workers have a 43% increased risk of developing a basal cell carcinoma and 77% increased risk of developing a squamous cell carcinoma.
Risk factors also include previous skin cancer, psoriasis and Bowen’s disease (pre-cursor to squamous cell carcinoma) as well as some occupational exposure to coal tar pitch, soot, mineral oils, arsenic and possibly creosotes and petroleum refining.
Non-malignant melanoma skin cancer symptoms
- Non-healing scaly area of skin.
- Non-healing small red or pink lump.
- Smooth lump with a ‘pearly’ appearance.
- Non-healing lump or sore that crusts over/bleeds/itches or sometimes breaks down and develops into an ulcer.
- Non-healing scaly area of skin or pink lumps.
- Non-healing area of skin that may have a hard, crusty surface that is sometimes tender and may bleed.
Diagnosis of non-malignant melanoma skin cancer
Investigations will include:
- Skin biopsy and possibly dermatoscopy.
Non-malignant melanoma skin cancer treatment
Depends on several factors:
- The type of skin cancer.
- The size and position of the tumour.
- The stage of the cancer.
Surgery will depend on the size and position of the skin tumour. Initially it will be an excision biopsy removing the lesion and a surrounding area of healthy tissue, which may be adequate for small tumours.
If the excision biopsy indicates that a tumour may not have been completely removed, further surgery (wide local excision) may be performed to remove more tissue to reduce the risk of recurrence.
In a few cases of squamous cell carcinoma, which are more aggressive than basal cell carcinomas, malignant cells may be found in the local lymph nodes and removal of these nodes may be advised.
Curettage and electrocautery can be used for superficial small basal cell carcinomas but its use is on the decline. It involves ‘scrapping away’ the skin tumour and then using an electric needle to destroy any remaining malignant cells.
This is using light sources in combination with light sensitising drugs to destroy the cancer cells. It is most useful for some large superficial tumours.
Radiotherapy is frequently used to treat these skin cancers and is very effective. Often they occur on areas of the body such as the face and neck where surgery may be quite disfiguring.
It is very useful for small and large tumours, for those that have spread into the deeper layers of the skin and those where surgery will have a poor cosmetic result. Also, may be the treatment of choice if surgery is declined or the patient is not fit for surgery.
Radiotherapy is sometimes prescribed post-surgery (adjuvant) to reduce the risk of recurrence and sometimes used to treat involved lymph nodes.
Topical chemotherapy is sometimes used for early basal cell carcinomas and squamous cell carcinomas. This will involve applying a cream containing the chemotherapy drug fluorouracil (5FU) to the area.
Immunotherapy is sometimes used for superficial early stage basal cell carcinomas and Bowen’s disease and involves applying imiquimod cream to the affected area.