Irregular pigmented lesion on the cheek

A GP referred this patient on the urgent cancer pathway as a suspected melanoma. Rightly so.

The lesion was new over the last year, growing and had scabbed a bit. On plain view it’s about 1cm diameter, mostly pink with some scattered dots of pigment, and a sinister asymmetrically located black area about 3-4 mm diameter at the top end. It stands out dramatically from the small flat brown lesions in the rest of the field of view (these are solar lentigines, you can call them sun spots or age spots if you like.). This needs dermoscopy.

The dermoscope amplifies naked eye features and reveals features that we could not otherwise see. The black area resolves to a deep blue-black, a central ulcer (sharply defined irregular orange area with blood clot) is revealed, and there are numerous brown and dark grey dots and clods scattered around. These are irregular in size, shape and distribution, some are ‘clods within clods’ (a hallmark of pBCC). We also see sharply focused vessels that taper and branch. These are often called ‘arborising’ (tree like) vessels and are a hallmark of basal cell cancers.

This is a typical example of a pigmented basal cell cancer. An experienced dermoscopist can usually, but not always, distinguish such lesions from melanoma, but don’t try to be too clever as there is overlap (*) and even experts can get it wrong, as I have proved more than once by showing pictures to experts in a quiz! However, the features here are very typical of pigmented BCC (pBCC).

It is a wise rule to treat all suspicious pigmented lesions with the same degree of urgency.

(*) clues that point to malignancy but do not reliably distinguish between melanoma and pBCC

-chaos

-brown, grey and blue dots and globules

-irregular pigmented blotches

-atypical vessels

For more details and lots of examples, see my inexpensive Kindle e-book, Skin Cancer Diagnosis Made Easy, only £9.50