Strengths and Limitations:
This is the largest, single-centre prospective analysis of prognostic
factors for AYA with bone sarcomas globally, with the first prognostic
model tailored for AYA with generalizable results for LMIC.
Limitations include the shorter follow-up and lower number of AYA with
Ewing’s sarcoma, which is as expected for a rare cancer. Additionally,
the prognostic scores for metastatic osteosarcoma, and for both
non-metastatic and metastatic osteosarcoma could not be validated in a
separation validation cohort due to lower sample sizes. Socioeconomic
backgrounds of our patients were not assessed with objective scales such
as the Kuppuswamy scale; however, surrogate parameters such as treatment
duration as an indicator for compliance, prior inadvertent treatment and
protocol completion were included in the analysis.