Abstract

We have experienced 6 cases of acral lentiginous melanoma (ALM) in the past 23 years. There was no sex defference; 3 male cases and 3 female cases. The age of the patients ranged from 30 to 75. Of the 6 lesions, 5 occurred on the sole of the foot and one on the finger. The size of the lesions ranged from 1.5×0.9mm to 60.0×63.0mm and histological examination revealed their tumor thickness from 0.41mm to 10.00mm. One of the 6 cases only had a regional lymph node involvement, the others had none. All lesions were resected at 2 to 5cm out of their margin. Two cases evaluated as Clark level IV or V developed metastasis after operation. One of them of which tumor thickness was 10.00mm died from brain metastasis. The others have been disease free for 2 to 19 years after operation.
Cascinelli members of WHO melanoma program, have reported world wide stastical evaluation of the prognosis of the tumor thickness. However, they did not show any precise data about ALM that is the most common type in the Japanese. We reported 6 ALM cases discussing their tumor thickness and prognosis. To know the prognosis of ALM, furthermore investigations are required.