Shiny white lines on the leg: melanoma? Case 2611001
A 47-year-old man, a slowly growing lesion on the lower leg. Under polarized light: shiny white lines, an atypical network, dotted vessels and a milky-red area.
The 2-Step read
Step 1: disorganized, so straight to step 2A.
Step 2A: no criteria for BCC, none for SCC, but criteria for melanoma. Excise.
Diagnosis: dermatofibroma (histopathology).
Pearl: shiny white lines mean dermal fibrosis, and dermatofibromas have plenty of it. In a disorganized lesion with melanoma clues, the algorithm still says excise.
Your turn
Would you have cut it? Yes / no, and why?
Which feature would keep a dermatofibroma on your list here?
🔒 Premium teaching point: “Now you see them: shiny white lines”
When do the same lines mean melanoma? 22% of melanomas but only 1.6% of benign lesions show them, and the company they keep tells you which is which. The 3-minute deep dive covers:
what counts as a shiny white line, and what does not;
why they shine: collagen and polarized light;
the evidence in numbers, including invasion;
dermatofibroma, scar, BCC or melanoma: reading the company;
five steps at the dermatoscope.
Go deeper
More on dermatofibroma: the complete lecture Universe of Dermatofibromas → Universe of Dermatofibromas (included in All Access, 20% off for Evidence Club members).