We reported a 62 year-old male who had a verrucous malignant melanoma on his back of left hand, Remarkable findings of this case are summarized as follows; 1) the measurement of 5-S-CD value in the crust and the findings of touch-fluorescence method from the exudate were useful for the preoperative diagnosis of melanoma, 2) the accuracy of these methods was confirmed by the fluorecence microscopic findings of formalin-fixed paraffin-embedded unstained specimen and immunostainig for HMB-45 and NK1C3 with the same specimens, 3) the measurement of cellular DNA content and the cytofluometric histogram in the vertical growth portion exhibited 3.40C, aneuploid pattern, respectivily, whereas in the radial growth portion, it showed 2.40C, and diploid pattern, respectively. We emphasized that verrucous malignant melanoma is an important clinical form which requires a careful attention to avoid inadequate treatment, because this type of melanoma is sometimes misdiagnosed as a seborrheic keratosis.
