High dose methotrexate containing regimen in pediatric non-metastatic extremity osteosarcoma patients: experience from a tertiary cancer center in India

Abstract

Methotrexate containing chemotherapy is less commonly used for treatment of osteosarcoma in resource limited settings. We present our experience with the administration of high dose methotrexate (HDMTX) containing chemotherapy over a period of three years. Children between 1 and 14 years of age with newly diagnosed nonmetastatic extremity osteosarcoma, registered in Pediatric Oncology Department of a tertiary care cancer center in South India between 1st January 2016 and 31st December 2018 and receiving MAP chemotherapy were included. Patients in this study received HDMTX at 12 g/m2. Twenty two patients were included. After neoadjuvant chemotherapy, 20 patients underwent surgery (limb salvage surgery in 16, amputation in 4). The median time from initiation of chemotherapy to surgery was 97.5 days. Eighteen of 22 patients (81.8%) completed planned chemotherapy in our cohort, one patient was lost to follow up after progression and three patients required change of chemotherapy due to toxicities. Of a total of 227 cycles of HDMTX infusions in 22 patients, delayed clearance occurred in 22 cycles (9.7%). Major toxicities were myelosuppression (30 episodes in 17 patients), blood stream infections (24 episodes in 15 patients) and mucositis (15 episodes in 10 patients). Hearing loss was documented in 7 patients. There was no treatment related mortality. Chemotherapy was completed in a median duration of 38.5 weeks. Administration of high dose methotrexate containing chemotherapy is feasible in pediatric patients with osteosarcoma, even in resource limited settings, if there are facilities for hydration, determination of methotrexate levels and good supportive care.