Formaldehyde-induced fluorescence method for touch preparations from amelanotic melanoma tissues: a simple and rapid method for the demonstration of melanogenic activities of amelanotic melanoma cells.

: Touch preparations from four amelanotic melanoma tissue samples were studied with the formaldehyde-induced fluorescence method. Fluorescent amelanotic melanoma cells could easily be detected under a fluorescence microscope. The fluorescence microscopic pictures obtained by the touch-fluorescence method were equally evaluated with those obtained by the classical fluorescence method. The method made it possible to demonstrate the melanogenic activity of amelanotic melanoma cells within 30 min. The routine application of this method to the diagnosis of amelanotic melanoma is suggested.