Twenty-three patients with inoperable skeletal tumors were treated with intraarterial cis-platinum prior to attempted surgery. The antitumor effect of intraarterial cis-platinum was monitored clinically by radiologic imaging techniques, and whenever possible, evaluated histopathologically by examinatin of surgical or biopsy tumor specimens. Objective responses were noted in 12 patients (52%) and included 2 complete, 7 partial and 3 less-than-partial remissions lasting from 14 to 70 weeks. Limb-saving surgery or hemipelvectomy became subsequently feasible in four and one patients respectively. Preoperative intraarterial cis-platinum is a safe procedure which might be used effectively in combination with other, more conventioal postoperative adjuvant chemotherapy against skeletal tumors.