Prognosis

The thickness of the melanoma, and the presence or absence of ulceration, are major determinants of the prognosis. Thicker melanomas have a worse prognosis than thinner melanomas, ulceration is associated with a worse prognosis.

For a melanoma of <1mm thickness, a 1 cm WLE is appropriate, for a melanoma of 1-2 mm in thickness a 1-2 cm WLE is appropriate, for 2-4 mm a 2-3 cm WLE is appropriate, and for > 4cm, a > 3cm WLE is appropriate.

Investigation

The investigation and management of a patient with malignant melanoma is usually discussed in a multi-disciplinary team (MDT) meeting: these are held weekly at Addenbrooke’s hospital. The MDT will recommend CT scanning the chest, abdomen, and pelvis in patients with moderate or high risk melanomas, (and in some patients the brain as well) to make sure that the melanoma has not spread to these organs.

The MDT will recommend, for all but the most low-risk tumours, that the patient be offered sentinel lymph node biopsy (SLNB). This is an operation that allows the sampling of the lymph node most likely to contain melanoma. If the result is positive, the patient can be offered complete removal of the lymph glands (for example in the groin or axilla) as a separate operation.

Wide local excision

Patients that have had a melanoma removed and the diagnosis confirmed by histological analysis are offered wide-local-excision (WLE). This involves removal of a cuff of skin around the scar from the excision biopsy: the aim is to reduce the potential for local recurrence of the melanoma in the nearby skin. Patients undergoing SLNB will have this investigation performed at the same time as the WLE.

Making the diagnosis

The diagnosis can be made from a consideration of the history, and examination of the lesion. Simple algorithms such at the 7-point checklist can help clinicians unfamiliar with melanoma to recognize worrying lesions.
Lesions with a score of ≥ 3 should be referred to an expert

Major Features (score 2-points)
Change in shape
Change in size
Change in colour

Minor signs (score 1-point)
Over 7 mm diameter
Inflammation
Crusting or bleeding
Irritation or itch

Patients with lesions that are suspicious of melanoma should be referred to an appropriate specialist for urgent review with 2-weeks.

Radiotherapy and chemotherapy

The use of radiotherapy is usually as a second line treatment after surgery to the lymph glands, or in areas of the body where surgery is not possible (such as the brain). Chemotherapy is offered to patients with advanced disease on the advice of the MDT.