Dermoscopy is useful in the assessment of a blue-grey pigmented lesion on a trauma site. The need for biopsy must always be considered carefully.
A 47-year-old man with a history of significant sun exposure presented for a full skin check. He had no personal history or family history of melanoma or other skin cancer.
On examination, an area of diffuse blue-grey pigmentation was found on the patient’s left knee (Figure 1a). He reported that he had fallen off his bicycle many times, landing on asphalt surfaces, and that the pigmentation had been present and stable since one of these falls. Dermoscopy showed grouped blue-grey dots and globules with adjacent areas of scarring (Figure 1b). No features specific for a melanocytic lesion or basal cell carcinoma (BCC) were seen.