Blue-white variant of basal cell carcinoma as a mimicker of melanoma: Dermoscopic Analysis

Objective: Dermoscopic features of basal cell carcinoma (BCC) have been well described in the literature, however, blue white variant of BCC has recently been described as a mimicker of melanoma. When reviewing the literature, it seems that there is just one original research about this special type of BCC. Here we aimed to evaluate this special and challenging variant of BCC cases of two dermatology departments from different regions of Turkey. 

Material and methods: Dermoscopic images of the histopathologically approved BCC cases  from two centers between the years 2015-2018 were reviewed. The cases showing diffuse blue white areas on dermoscopy were included in the study. The clinical and histopathological features, dermoscopic images and demographic data of all the cases were evaluated

Results: We detected 15 (9.74 %) lesions of BCC with diffuse blue-white dermoscopic pattern from 15 different patients among 154 cases of histopathologically confirmed basal cell carcinomas. All of the cases were located on the head region. All of the cases were excised with two main differantials: melanoma and BCC. The most common findings after blue white diffuse areas were irregular serpentine vessels (60.0 %), peripheral maple leaf like areas (46.6%) and ulceration (46.6%). The histopathological examination of all the cases were in keeping with nodular or noduloulcerative subtypes.

Conclusion: The present study, to the best of our knowledge, is the most comprehensive study regarding this rare and challenging presentation of BCC. The main differential diagnosis is melanoma. We suggest that it would be logical to consider blue white BCC in the lesions showing diffuse blue-white color. A careful dermoscopic examination regarding the presence of specific dermoscopic clues to basal cell carcinoma can provide a well-directed preliminary diagnostic evaluation. 

Keywords: Basal cell carcinoma, blue white, dermoscopy