Spoke wheel like structures
Spoke-wheel-like structures are well-circumscribed brown to gray-blue– brown radial projections that radiate out from a dark brown central hub. Sometimes the radial projections are not visible and instead one sees a concentric globule consisting of a round structure with a central darker hub, which is surrounded by a brown halo of pigment. In the absence of a pigment network, spoke-wheels are highly suggestive of basal cell carcinoma.
Histopathologically, they correspond to the nests of basal cell carcinoma emanating from the undersurface of the epidermis; a common finding in superficial basal cell carcinoma .