Seventeen cases of coetaneous malignant melanoma which admitted to Juntendo University Urayasu Hospital during the last 16 years (1984-1999) were statistically analyzed. A gradual increase in the number of new cases of this tumor was observed, probably due to the increasing ratio of older population in Urayasu City and surrounding areas. They involved 35.3% the trunk, 23.5% the sole, 17.6% the lower extremities, 5.9% the head and 5.9% the genitals. Two cases (11.7%) were in stage I, 7 cases (41.7%) in stage II and 8 cases (47.1%) in stage III. No patients had reached stage IV. Five-year survival ratio were 0% on stage I, 70% on stage II and 25% on stage III, which were poorer than the previously reported Japanese cases. Further improvement of lymphnode dissection and extended chemotherapies were expected. [Skin Cancer (Japan) 2000; 15: 143-146]
