Dermoscopy in the Diagnosis of Mycosis Fungoides: Can it Help?

INTRODUCTION: The diagnosis of mycosis fungoides (MF) is challenging since it can mimic a variety of benign skin conditions. Multiple biopsies for histopathologic and immunohistochemical examination are required to diagnose MF. Dermoscopy is an affordable, non-invasive device with expanding indications in dermatology, OBJECTIVES: To investigate the dermoscopic morphology of MF variants and assess the correlation between dermoscopic criteria, histopathologic, and immunohistochemical findings, METHODS: We included 88 patients with several MF variants (classic, hypopigmented, hyperpigmented, poikilodermatous, erythrodermic, and folliculotropic). The diagnosis was histopathologically and immunohistochemically confirmed. Dermoscopic findings were collected, statistically analyzed, and correlated with the results of histopathology and immunohistochemistry, RESULTS: All patients had MF diagnosis in H&E-stained sections. The majority revealed positive staining with CD3, 4, 8 and negative CD7. Orange-red areas of discoloration, short linear, and spermatozoa like blood vessels are the most frequent dermoscopic findings, while an analysis per MF variant was also performed. The frequently observed dermoscopic structures in classic MF were patchy whitish scales, dotted, short linear vessels, and spermatozoa-like vessels, CONCLUSIONS: Dermoscopy reveals a repetitive dermoscopic pattern in MF (non-homogenous pink to erythematous background, patchy areas of orange discoloration, patchy whitish scales, dotted and short linear blood vessels with some variations according to the clinical variant.