[P3-37] Toxicity on Central Nervous System by Antineoplastic Agents in Osteosarcoma: 6-year Experience of a Single Institute
[Introduction] Osteosarcoma is one of the most common malignant bone tumors in adolescents and young adults (AYA). Doxorubicin (DXR), cisplatin (CDDP), methotrexate (MTX) and ifosfamide (IFO) are commonly used as chemotherapy agents. They have been known as to be neurotoxic, however the detailed neurological features have been unexplored. [Methodology] This is a retrospective study of pediatric and AYA osteosarcoma patients in terms of CNS manifestations related with chemotherapy in our institute for the last 6 years. Patients with brain metastasis were excluded. [Results] Fourteen primary osteosarcoma patients (4 males and 10 females: 14 years as median age) were reviewed. Neurotoxic events occurred in 5 patients aged 11 to 15 years, all of which were female. Encephalopathy developed in 4 patients. The causative agents were MTX for 2 patients, IFO for 3 patients and combination of CDDP/DXR for 1 patient. All of them showed reversible manners and recovered soon after the discontinuation of chemotherapy. EEG showed diffuse slowing in background in 3 patients during chemotherapy, and regained normally after the suspension of chemotherapy. Encephalopathic conditions reappeared at the following chemotherapy in 2 patients. Myoclonic seizures frequently appeared in 1 patient, whose EEG presented continuous paroxysmal discharges during and after the chemotherapy. MRI and/or CT studies on these 5 patients exhibited normal findings. [Conclusion] All 5 patients with CNS toxicity by antineoplastic agents were teenaged females, supporting the previous reports that the gender of female is one of the risk factors for CNS toxicity. EEG was useful and brief way to identify encephalopathic and/or epileptic conditions during the chemotherapy on osteosarcoma.