Evaluation of in vivo reflectance confocal microscopy in the diagnosis of extramammary Paget's disease.

Extramammary Paget's disease (EMPD) is a rare cutaneous malignancy that most commonly affects the apocrine glands of older men and women. Because it is associated with other cancers, early diagnosis and evaluation are needed. This study is to evaluate the value of reflectance confocal microscopy (RCM) in diagnosing EMPD. A total of 73 patients with clinically suspicious diagnosis of EMPD were enrolled in this study, and the RCM device imaged their lesions. Moreover, 67 patients underwent skin biopsies to confirm the diagnosis. We retrospectively analyzed the results of RCM and histological diagnosis and then evaluated the RCM value of biopsy‐confirmed lesions. Based on the RCM image analysis, 54 of 73 (74.0%) patients were diagnosed with EMPD. Of all 67 biopsied lesions, 52 (77.6%) were EMPD. Then, we analyzed the RCM characteristics of 52 cases of biopsy‐confirmed EMPD, compared their RCM image characteristics of three different lesions of EMPD, and further concluded the key points of EMPD under RCM microscopy based on the 52 EMPD cases. Finally, we focused on the differential diagnosis of EMPD from other skin diseases. RCM showed great diagnostic value in diagnosing EMPD. [ABSTRACT FROM AUTHOR]