3 March: Q&A with Mr Simon Knight

There is an area on my back that at one time was a painless lump the size of a pound coin and  it is now red, swollen, and has caused tenderness around the area, I was told by my GP  that it might be a white mole or a cyst that has become inflamed? What does it sound like to you and should it be removed?

Mr Simon Knight, Consultant Plastic and Reconstructive Surgeon:

I think your General Practitioner is correct. This sounds like a sebaceous cyst which has become infected.

Sebaceous cysts are lumps that occur in the skin. They are caused by blockage of the sebaceous glands, which are the glands that produce the material which normally greases the skin.

The cysts are not harmful and, if left alone, they usually increase in size, painlessly. Occasionally, however, the contents of the cyst get infected. This causes the lump to become red, painful and swollen, and, if left untreated, it may develop into an abscess.

I would advise contacting your General Practitioner for antibiotic treatment, to deal with the present infection. Once the inflammation has completely subsided, the lump can be removed under local anaesthetic, to prevent recurrence of the problem.

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