1Division of Hematology/Oncology, The Hospital for Sick Children, Toronto, Ontario, Canada; 2Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada;3Cancer Research Program, Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada;4Institute for Health Policy, Evaluation and Management, University of Toronto, Toronto, Ontario, Canada;5Department of Medical Oncology, Princess Margaret Cancer Centre, Toronto, Ontario, Canada; 6Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada; 7Li Ka Shing Knowledge Institute, St. Michael’s Hospital, Toronto, Ontario, Canada,8Melbourne School of Population and Global Health, University of Melbourne, Melbourne, Victoria, Australia
Abstract Background : Location of cancer care (LOC: pediatric versus adult center) impacts outcomes in adolescents and young adults (AYA) with some cancer types. Data on impact of LOC on survival in AYA with osteogenic sarcoma (OGS) and Ewing sarcoma (EWS) are limited.Objectives : To compare differences in demographics, disease/treatment characteristics, and survival in a population-based cohort of AYA with OGS or EWS treated at pediatric versus adult centers Methods : The IMPACT Cohort captured demographic, disease, and treatment data for all AYA (15-21 years old) diagnosed with OGS and EWS in Ontario, Canada between 1992-2012. Patients were linked to provincial administrative healthcare databases. Outcomes were compared between patients treated in pediatric versus adult centers using appropriate statistical methods.Results : 137 AYA were diagnosed with OGS (LOC: 47 pediatric, 90 adult) and 84 with EWS (LOC: 38 pediatric, 46 adult). AYA treated at pediatric centers were more likely to be enrolled in a clinical trial (OGS 55% vs 1%, [p<0.001]; EWS 53% vs 2%, [p<0.001]) and received higher cumulative chemotherapy doses. Five-year event-free survival (EFS ± Standard Error) in OGS and EWS were 47% ± 4 and 43% ± 5, respectively. In multivariable analysis, the impact of LOC (pediatric vs adult center) on EFS in OGS (adjusted hazard ratio [HR] 1.15, 95% CI 0.58-2.27, P=0.69) and EWS (adjusted HR 1.82, 95% CI 0.97-3.43, P=0.06) were not statistically significant.Conclusion : Outcomes did not differ by LOC suggesting that AYA with bone tumors can be treated at either pediatric or adult centers.KEYWORDS : adolescent and young adult, Ewing sarcoma, event-free survival, locus of care, osteosarcoma, population-based