PMC3764943_01
Clinical and histological findings. a Reddish-brown, erosive macule on the back of the left fourth finger. b The biopsy specimen showed a thickened epidermis with parakeratosis, but no granular layer. An abnormal, stratified arrangement and cytologically atypical keratinocytes were also observed (HE staining, x40). c Numerous signet-ring cells with nuclei that are crescentically compressed to the cellular border (HE staining, x250). d The border of the skin lesion also shows focal parakeratosis, loss of the normal stratified arrangement of the epidermis and the presence of signet-ring cells (HE staining, x100).
cde-0005-0215-g01.jpg
PMC3764943_01_cde-0005-0215-g01.jpg
F1
Physical examination revealed a 31 x 21 mm, reddish-brown, erosive macule on the back of the left fourth finger (fig. 1a). We also observed an abnormal stratified arrangement, cytologically atypical keratinocytes (fig. 1b) and an inflammatory cell infiltrate in the dermis. Notably, numerous signet-ring cells with crescentically compressed nuclei were seen extending to the cellular border (fig. 1c). Signet-ring cells were present, both at the border and throughout the tumor (fig. 1d).