Liability in the context of misdiagnosis of melanoma in Australia.

Malignant melanoma is a serious and relatively common condition, the diagnosis of which may be difficult. In a recent Supreme Court of New South Wales case, misdiagnosis of melanoma occurred, but there was failure to establish causation of the patient's poor prognosis. Aggressive melanomas may grow quickly, fail to conform to standard and commonly taught diagnostic criteria, and frequently escape early detection. In the event of uncertain diagnosis or failed treatment of a lesion, an appropriate standard of care is full excisional biopsy if not previously performed, or referral of the case to an appropriate specialist or melanoma centre. Clinicians should remain aware of the existence of higher-risk, easily misdiagnosed melanomas with a high mortality rate. Therefore, they should aim to identify these at the earliest opportunity.

Merkel cell carcinoma and multiple cutaneous squamous cell carcinomas in a patient with pityriasis rubra pilaris.

A 79-year-old female was diagnosed with Merkel cell carcinoma (MCC) and multiple cutaneous squamous cell carcinomas (SCC) occurring on a background of pityriasis rubra pilaris. At the time of initial diagnosis and treatment for upper limb MCC, axillary nodal metastases were clinically evident. In the ensuing months, she developed multiple rapidly progressing SCC and eventually a left arm soft tissue deposit of metastatic MCC. Treatment involved multiple courses of fractionated radiotherapy. The salient clinical features and supporting evidence for this case are presented.