10th August 2020

A mother has brought her 10-month old daughter to clinic, and is concerned about the development of numerous small patches of dark discolouration on her lips

A mother has brought her 10-month old daughter to clinic and is concerned about the development of numerous small patches of dark discolouration on her lips. The lesions are flat, dark brown in colour and vary in size from 1mm to 5mm in diameter, with no clear pattern to the distribution. They appeared around a month ago and do not appear to be causing any distress – the patient’s mother is concerned by the appearance and whether these are a sign of skin cancer. There are no other lesions present elsewhere on the patient’s body and no birth marks. There is no history of skin cancer within the family, although the patient’s grandmother died of bowel cancer at the age of 55.

Which of the following is the most likely cause?

Select the SINGLE most appropriate option from the list below. Select ONE option only.