Neoadjuvant chemotherapy for high grade osteosarcoma of the extremities: long-term results for patients treated according to the Rizzoli IOR/OS-3b protocol

Abstract

The results of the Rizzoli IOR/OS-3b neoadjuvant protocol for the treatment of osteosarcoma of the extremity are reported. Preoperative chemotherapy consisted of two cycles of high-dose methotrexate (HDMTX i.v.), followed by a combination of cisplatin (CDP i.a.)/ doxorubicin (ADM i.v.). Postoperatively all patients, regardless of the histologic response, received 3 more cycles of MTX, CDP/ADM alternated with 3 cycles of ifosfamide. In the study performed between January and December 1992 43 patients were enrolled and limb salvage was performed in 39 of them (91%). The histologic response to chemotherapy was good (90% or more tumor necrosis) in 24 patients (56%) and poor (less than 90% tumor necrosis) in 19 (44%). With a minimum follow-up of 7 years, 23 pts (53%) remained continuously free of disease, 19 relapsed and one died due to unrelated cause. In spite of the high number of limb salvages performed, only 2 local recurrences were registered. The 7-year event-free survival and overall survival were, respectively, 53% and 68%. The hematopoietic and extrahematopoietic toxicity experienced by the patients during the entire treatment was relatively mild. These long-term results confirm that, with neoadjuvant chemotherapy, it is possible to cure more than 60% of patients with osteosarcoma of the extremities, avoiding amputation in most of them. These results, however, are no better than those achieved in our previous study IOR/OS-3a, in which only poor responder patients received ifosfamide during the postoperative treatment.