Abstract
A 59-year-old woman presented with a gradually growing pigmented stria on the nail of her right big toe, which had become slightly deformed with pain. Partial removal of the nail plate revealed a black lesion with bloody crusts on the nail bed. Dermoscopically, the principal lesion comprised a structureless area with whitish veils, and pigmented spots on the toe tip with a pigmented fibrillar pattern in both the cristae and sulci. Although we obtained a negative result by using the touch-fluorescence method on the surface of the lesion, the 5-S-cysteinyldopa (5-S-CD) level in exudate in the gauze was as high as 369.0ng/PCAml. Taken together with the clinical and dermoscopic findings, the result of 5-S-CD in the exudate led us to be able to make a diagnosis of malignant melanoma. In this paper we also report our method of preoperative diagnosis of ungual malignant melanoma. [Skin Cancer (Japan) 2006; 21: 194-198]
