Bone marrow involvement in metastatic pediatric ewing sarcoma

To evaluate the frequency of bone marrow involvement with metastatic lung and bone sites in newly-diagnosed pediatric patients with Ewing sarcoma (ES). Study Design: An observational study. Place and Duration of Study:Shaukat Khanum Memorial Cancer Hospital, Lahore, Pakistan, from January 2010 to October 2015. Methodology:Newly-diagnosed pediatric-age patients with ES were inducted. Ten patients were excluded because bone marrow aspiration/biopsy (BMAB) was not done. Patients' medical records were reviewed for data collection of age, diagnosis, tumor volume, bone marrow diagnosis, metastatic work-up and outcomes. Results: A total of 139 patients with median age of 12 years were identified. The median volume of tumors was 529 ml. Eleven patients had bone marrow (BM) disease involvement. Five (45.5%) had bone metastatic disease and 1 (9%) had both pulmonary and bone metastases. Four patients (31.1%) with positive BM had primary limb disease. Conclusion: Ewing sarcoma patients with bone metastatic disease have a higher frequency of BM involvement. However, BM can be involved without metastatic disease. BMAB should still be considered at staging for newly diagnosed pediatric patients with localized ES. (author)