Answer to last month's Clinical Quiz

Question:

A 65 years old man has noted multiple brownish nodules and plaques on the scalp and face for 8 years. The largest lesion is shown in the picture.

Answer: D. Seborrhoeic keratosis

Seborrhoeic keratosis is a common benign skin tumour. It usually develops in people older than 30 years of age. The number of lesions can vary from one to hundreds. It is commonly found on the face and trunk.

Seborrhoeic keratosis usually begins as a brown macule, which then grows to become a nodule or a plaque with rough surface. It typically has a 'stuck-on' appearance. The colour may vary from light brown, dark brown to black. The differential diagnoses include benign melanocytic naevus, dysplastic naevus and malignant melanoma.

There are various treatment modalities for seborrhoeic keratosis. These include cryotherapy, electrodesiccation, curettage, shave biopsy with electrodesiccation and laser therapy. Excision is usually not the treatment of choice as the ultimate cosmetic appearance is likely to be unsatisfactory. However, when the lesion is not typical of a benign seborrhoeic keratosis, histological examination should be performed so that a malignant melanoma or a dysplastic naevus will not be missed.