Heavily pigmented melanocytic neoplasms: comparison of two melanin-bleaching techniques and subsequent immunohistochemical staining.

The effect of melanin bleaching using permanganate/oxalate and dilute hydrogen peroxide on subsequent immunohistochemical staining of heavily pigmented melanocytic neoplasms is investigated. Permanganate/oxalate precluded the use of some antibodies but allowed much faster bleaching times, whereas dilute hydrogen peroxide enabled a full range of antibodies to be used, yet bleaching times were far longer. Each technique has advantages; however, the choice of method should be determined by the nature of the information needed to make a diagnosis and the speed at which a report is required.