5 CONCLUSIONS
Histological necrosis post neoadjuvant chemotherapy is prognostic of
outcomes on a non-HDMTX based chemotherapy backbone in children with
osteosarcoma. Tumor necrosis at a cut-off of 90% in localized disease
is a good prognostic tool on a non-HDMTX based chemotherapy backbone,
though best outcomes are seen with 100% TN, but 70% TN and other lower
cut-offs require further exploration for survival predictive value. A
lower cut-off of 70% (or other) in metastatic disease could be used for
prognostication, which needs validation in a larger cohort. Amputation
and male gender predict poor histological necrosis, probably driven by
bad biology.