Abstract

Cytoplasmic vacuolization is a distinct artifact characterized by vacuoles in the epidermis, dermis and/or subcutis which has been linked to improper tissue fixation, cold artifact, biocides used in every day products as well as intradermal injection of local anesthetics. We report a 52-year-old woman with no significant past medical history who presented for evaluation of a long-standing papule on her temporal scalp which would intermittently ooze and scab. On exam, there was a bright pink patch with a lateral 5mm pink, shiny papule and overlying erosion with crust. Prior to local anesthesia and shave biopsy, a medical assistant gently removed the crust with hydrogen peroxide. H&E stained sections showed a compound melanocytic nevus with large vacuoles involving the epidermis and papillary dermis. Given the history of hydrogen peroxide just prior to shave biopsy and lack of similar findings in other skin biopsies at the time of reading this particular biopsy, a final diagnosis of compound nevus with artifact likely secondary to hydrogen peroxide was made. To our knowledge, cytoplasmic vacuolization secondary to the use of hydrogen peroxide has not previously been reported. There have been several small retrospective case series with the aim to  further characterize cytoplasmic vacuolization and its etiology. We present this case to reflect the importance of recognizing potential artifacts that can be seen in tissue specimens in dermatopathology.