sQuiz your knowledge: A solitary asymptomatic nodule on the arm

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Résumé

A 39-year-old man consulted for a skin lesion that had
appeared on his arm 10 months before and had progressively
reached 2 cm in diameter (figure 1A) . The
lesion was painless. There was no history of injury
or vaccine injection, and no locoregional adenopathy.
General examination was otherwise normal. Polarized dermoscopy
showed a non-pigmented tumour, with a whitish
central structureless area, and some linear and dilated vessels
at the periphery (figure 1B). Surgical removal was
performed.
Histopathology showed a non-encapsulated, fairly well limited
tumour, located in the dermis and the hypodermis,
surrounded by mild epidermal hyperplasia and focal epidermal
ulceration (figure 1C). The proliferating cells were
large, with eosinophil and granular cytoplasm, and a vesicular
nucleus (figure 1D). There were a few mitoses and
a few atypical cells. Immmunostaining showed granular
cells expressing PS100, CD68 and neuron-specific enolase
(NSE) (figure 1E), with no expression of cytokeratin AE1-
AE3. Numerous small vessels were evidenced within the
tumour. A few clusters of lymphocytes were seen at the
periphery of the tumour.

Mots-clés

Solitary, Asymptomatic nodule, Arm, Abrikossoff