Dermoscopy in pigmented squamous cell carcinoma

Background: The diagnosis of squamous cell carcinoma (SCC) is, generally, a clinical diagnosis, but in some cases, when the lesion is pigmented, as in our case, the differential diagnosis between pigmented SCC and other pigmented skin lesions, in particular melanocytic lesions, is difficult. Dermoscopy may improve the early diagnosis of SCC and thus play a role in its preoperative classification. However, its potential role has been hampered so far by the fact that little is known about the dermoscopic features of pigmented SCC. Objective: We report the case of a rare pigmented SCC dermoscopically mimicking a melanocytic lesion whose dermoscopic features have been investigated. Conclusion: On the basis of the literature and our experience, pigmented SCC can present dermoscopic features typical of melanocytic lesions, such as radial streaks, globules, and homogeneous blue pigmentation, and can lead dermatologists to diagnostic errors. © 2009 Canadian Dermatology Association.