What is the cause of this solitary nodule, and how should it be treated?
A 70-year-old woman has a seven-month history of a small painful nodule on the superior part of the rim of her right ear. The nodule has not been increasing in size. She was referred because of concerns that it might be a skin cancer. She generally sleeps on her right side but now finds this difficult because of her painful ear.
The nodule is red, tender and centrally scaly. Elsewhere, the cartilage of the rim of both ears has a few smooth bumps with no overlying inflammation. She is a keen gardener and lawn bowler, has sun damaged skin and has previously had some basal and squamous cell carcinomas excised from other sites.