Author Affiliations: Department of Dermatology, Hokkaido University Graduate School of Medicine, Sapporo, Japan.
A parallel ridge pattern under dermoscopy is a prominent dermoscopic finding in macules of malignant melanoma on the palms and soles. Herein, we present a case of pagetoid dyskeratosis with a parallel ridge pattern under dermoscopy.
A 34-year-old Japanese woman was seen with a 1-year history of brownish pigmentation on her left small finger, which had expanded and intensified in color during the previous 2 weeks (Figure 1A). She was an office worker and a nonsmoker. There was no history of contact with chemical substances or dyes.
Toyonaga E, Inokuma D, Abe Y, Abe R, Shimizu H. Pagetoid Dyskeratosis With Parallel Ridge Pattern Under Dermoscopy. JAMA Dermatol. 2013;149(1):109-111. doi:10.1001/archdermatol.2012.3201