High-dose methotrexate (HDMTX), adriamy-overall and disease-free survival rates were 70% cin (ADR), and cisplatinum (CDDP) are effective and 59%, respectively. Factors which favorably agents in the treatment of osteogenic sarcoma influenced prognosis on univariate analysis were (OS). Individual patient doses are determined a cumulative ADR dose of ΟΎ300 mg/m 2 by prior successful clinical trials but may be (P Ο 0.0002) and a cumulative MTX dose ΟΎ114 reduced due to ongoing toxicities. It is unknown gm/m 2 (P Ο 0.0048). By multivariate analysis whether individualized dose reductions of these only the cumulative ADR dose ΟΎ300 mg/m 2 redrugs influence disease outcome. We retrospec-tained prognostic value. We conclude that adjutively studied 27 consecutively enrolled chil-vant chemotherapy dosages may need to be addren treated with HDMTX, ADR, and CDDP as justed for therapeutic efficacy in addition to adjuvant chemotherapy for OS, for correlations adjustments made for toxicity. The effect of differbetween disease outcome and several charac-ent cumulative HDMTX and ADR dosages on teristics of drug dosing: the cumulative MTX, prognosis in osteosarcoma patients needs to be CDDP, and ADR doses administered and the evaluated in a prospective trial. Med. Pediatr. mean MTX blood levels for each patient. With