Abstract
We investigated the characteristic dermoscopic features of early lesions of malignant melanoma. On dermoscopy, malignant melanoma in situ and the macular portions of invasive malignant melanoma affecting glabrous skin showed accentuated pigmentation on the ridges of the skin markings, which are arranged in parallel. This “parallel ridge pattern” was exclusively found in malignant melanoma in situ and the macular portion of invasive malignant melanoma. In contrast, benign melanocytic nevi on glabrous skin showed, in most cases, one of the following 3 typical dermoscopic patterns: (1) parallel furrow pattern, (2) lattice-like pattern, and (3) fibrillar or filamentous pattern.
On non-glabrous skin, malignant melanoma in situ and the macular portion of invasive malignant melanoma showed highly irregular pigment network, pseudopods, radial streaming and irregular black dots or brown globules. Other pigmented lesions such as basal cell carcinoma, seborrheic keratosis, solar lentigo and black heel also showed distinctive dermoscopic features, respectively. Because of these characteristic features, we can effectively detect early melanoma using this noninvasive method. [Skin Cancer (Japan) 2001; 16: 13-21]
