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Solitary red patches – 17 cases

One is often faced with a solitary red patch of skin to diagnose. Some clues to differentiate the most common conditions are presented in this quiz.

It is particularly important to identify malignant tumours.

For each of the seventeen cases, study the image(s) and then answer the questions. You can click on the image to view a larger version if required.

Each case should take approximately 2 minutes to complete. There is a list of suggested further reading material at the end of the quiz.

Case 1

Superficial basal cell carcinoma with dermoscopic view

Superficial basal cell carcinoma presents as a slowly growing irregular plaque, most often on upper trunk or limbs. It tends to be bluish-red. Stretch the skin to reveal a shiny rim. Use the dermatoscope to identify telangiectasia, often arborising, and ulceration.

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