Figure 1: (a) Ulcer of 1.5 cm × 0.7 cm size over right ring finger nail bed with destruction of overlying nail plate. (b) X-ray of the right ring finger revealed osteophyte at the distal interphalangeal joint with widening of the trabeculae. (c) Biopsy shows epidermal proliferation with crowding of keratinocytes with atypical cells above the basal layer with formation of horn pearls. The dermis shows moderately dense lymphoplasmocytic infiltrate (H and E, ×100). (d) Biopsy shows atypical cells with altered nuclear cytoplasmic ratio with increased mitotic figures (H and E, ×400).