Abstract

We reported three cases of malignant melanoma in situ. Case 1: A 36 years old, female. Superficial spreading melanoma in situ on the upper back. Case 2 : A 56 years old, male. Acral lentiginous melanoma in situ on the left sole. Case 3 : A 59 years old, male. Ungual melanoma in situ on the right thumb. Histopathologically atypical melanocytes are within the epidermis in all cases. We treated them by local resection and skin graft.
We observed them with dermatoscope. The features of the lesions of superficial spreading melanoma in situ with dermatoscope were characterized by irregular pigment network, radial streaming and pseudpods in the periphery. And those of acral lentiginous melanoma in situ were characterized by diffuse pigmentation unconcerned with sulcus cutis and crista cutis and hyperpigmentation on the crista cutis rather than sulcus cutis. Dermatoscope proved to be useful for the correct diagnosis of early malignant melanoma.