Key message
Dermatofibrosarcoma protuberans may be very difficult to identify on the basis of clinical and dermoscopic features, in particular in the presence of scars. Because of the variability in the dermoscopic patterns,
A 54-year-old woman presented with a 3- × 4-cm asymptomatic brown plaque overlying a linear scar, resulting from the removal of a cystlike lesion on the abdomen a year earlier. No histologic examination was performed (Fig 1, A).
The dermoscopic examination showed central linear white and pink areas surrounded by structureless light-brown areas with focal pigmented reticular lines. No vascular pattern were seen. We performed an incisional biopsy of the pink area (Fig 1, B).
At the epidermal level we observed normal stratum granulosum and spinosum that resembled a honeycomb pattern with dark nuclei surrounded by bright-white cytoplasm.
The dermoepidermal junction displayed a focal loss of normal “edged papillae” (dark, round areas surrounded by bright rings of the basal layer cells) (Fig 2) with bright elongated cells in the papillary dermis corresponding to spindled tumor cells (Fig 2, B).
Histopathological examination revealed oval to spindle-shaped cells arranged in a storiform pattern in the dermis (Fig 3, A). Immunohistochemistry was positive for CD34 cells (Fig 3, B), which had reached the overlying epidermis. Dermatofibrosarcoma protuberans was diagnosed. Dermatofibrosarcoma protuberans may be very difficult to identify on the basis of clinical and dermoscopic features, in particular in the presence of scars. Because of the variability in the dermoscopic patterns, Key message
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Conflicts of interest: None declared.