Facts and figures about malignant melanoma skin cancer
Melanoma is the 5th most common cancer in the UK. Overall slightly higher incidence in females, male to female ratio approximately 10:11. In the 20-24 year age group the male to female ratio is 4:10 but from 60 years of age it is higher in men i.e. 11:10 in the 60-64years age group and 17:10 in those aged 85+ years.
Incidence rises steadily from the age of 20 years and the number of cases diagnosed each year is increasing.
Risk factors are sun exposure and sunbeds (ultra violet radiation) particularly in Caucasians, 86% of cases are linked to UVR exposure. Also, a family history of malignant melanoma, particularly if one or more relatives were diagnosed at under 30 years of age, large number of moles (100+), previous malignant melanoma, Crohn’s disease and ulcerative colitis, HIV and AIDS infection. Also, some occupational exposure to coal tar pitch, soot, mineral oils, arsenic and possibly creosotes and petroleum refining.
Aggressive tumours that will spread quickly to other parts of the body if not treated early, not always detected early as may resemble normal mole for some time.
Malignant melanoma skin cancer symptoms
- Mole getting bigger.
- Change in shape of a mole, particularly if developing an irregular edge.
- Change in the colour of a mole.
- Loss of symmetry- 2 halves of the mole looked noticeably different.
- Mole becoming, itchy, painful or inflamed.
- Mole bleeding or crusting over.
Diagnosis of malignant melanoma skin cancer
Investigations will include:
- Possibly dermatoscopy.
- Skin biopsy – mole removed with surrounding tissue and sent for analysis.
- Ultrasound scan – if malignant melanoma greater than 1mm deep or lymph nodes in the area are swollen.
- Sentinel node biopsy- if positive will probably remove other lymph nodes in the area (lymphadenectomy).
- CT scan – if malignant melanoma cells are found in the lymph nodes or the melanoma is more than 4mm deep.
Malignant melanoma skin cancer treatment
Depends on several factors:
- The depth of melanoma.
- The spread of disease.
Surgery is the main treatment for malignant melanoma; the extent of the surgery will depend on any residual mole in the surrounding skin of the biopsy site, depth of the melanoma growth beneath the skin, the position of the melanoma on the body and the potential impact of surgery.
In early stage and where there are no lymph nodes involved, surgery to remove the melanoma may be adequate. In medium stage, where the melanoma is 2mm or thicker or thicker than 1mm and ulcerated or the disease has spread into the skin and lymph nodes, surgery to remove the melanoma will need to be followed by surgery to remove more tissue, may be a wide local excision (WLE) usually down to the level of the muscle to reduce the risk of recurrence.
There is a substantial risk of recurrence or spread to other parts of the body in stage 2 and above.
Radiotherapy may be used in advanced malignant melanoma cases where the disease has spread to shrink the tumour and control symptoms. These tumours tend to spread to the liver, brain, bone and lung.
Chemotherapy is being used in some clinical trials for advanced malignant melanoma equating the use of post-operative (adjuvant) chemotherapy. Drugs most commonly used are decarbazine DTIC, carmustine (BCNU), vinblastine or cisplatin.
Biological therapies are being used in advanced cases of malignant melanoma to try and control the disease. The drugs tend to work by stopping the melanoma cells producing BRAF protein which would encourage cell growth.
Two such drugs are vemurafenib and dabrafenib.
Cancer vaccines are being researched which may stimulate the immune system to fight the malignant melanoma in advanced cases or those at high risk of recurrence.