High-dose methotrexate (MTX) chemotherapy extends the duration of hospitalization and introduces the risks of serious complications related to delayed MTX excretion. The treatment of delayed MTX excretion is largely dependent on invasive measures such as hemodialysis because the clinical data regarding the efficacy or safety of carboxypetidase G(2) is limited. We report here on the cases of two pediatric osteosarcoma patients with delayed MTX excretion and who were successfully managed using supportive measures. Potential life-threatening complications were prevented by administering high doses of leucovorin.
Keywords: Child; Complication; Management; Methotrexate; Osteosarcoma.