When to biopsy a foot ulcer? Seven cases of malignant melanoma presenting as foot ulcers

Over the last four years we have diagnosed seven cases of malignant melanoma which were referred to our diabetes foot ulcer clinic. In five of our patients who had diabetes the lesion was initially misdiagnosed as a neuropathic foot ulcer. Acral melanoma is frequently misdiagnosed due to its less common location and because it does not fit the ‘ changing mole’ pattern. It has been mistaken for plantar warts, fungal infections, hyperkeratotic lesions and non-healing ulcers. Early detection of malignant melanoma greatly enhances the prognosis but primary melanoma of the foot has been associated with a poorer survival rate. In the light of our cases we advocate a high index of suspicion for an alternative aetiology such as melanoma in cases where the ulcer looks atypical and refuses to heal with conventional treatment, if the ulcer is in an unusual anatomical site or when one cannot easily postulate a cause for development of the ulcer for any other reason. If the ulcer looks ‘ suspicious' and atypical, a dermatology opinion should be sought early and a biopsy should be considered. Copyright © 2008 John Wiley & Sons.