Intra-arterial CDDP is a highly effective method of achieving destruction of the primary tumor. From 1984 to 1988, 6 patients were treated with intraarterial CDDP (100 mg/m2). Five patients received three courses and one received two courses. The age of patients ranged from 11 to 27 years. According to the Enneking's surgical staging, all patients had stage II B disease. Analyzing the DNA ploidy pattern, one patient was near diploidy, and the others were hyperploid. Evidence of response was demonstrated by a decrease in tumor size (67%), a marginal sclerosis in soft tissue mass (83%), and a drop of serum alkaline phosphatase levels (100%). The CT scan was considered the most important parameter for determining response and defining the extent of tumor for wide excision. It is suspected that it is possible to apply a minimized wide resection for the primary tumor with a well-defined marginal sclerosis.