Progression before local therapy

A single-institution retrospective analysis reported on early progression of osteosarcoma before local control.[41] Among 195 patients aged 18 years or younger, 25 (81%) had local-site progression only, and 6 patients had combined local- and metastatic-sites progression. The authors did not prospectively identify patients with clinical features that might suggest telangiectatic osteosarcoma with increased necrosis and hemorrhage, which might be an explanation for apparent progression. For the entire cohort, the 5-year EFS rate was 27.2%, and the OS rate was 31.3%. Patients with good necrosis had better 5-year EFS and OS rates (66.7% and 66.7%, respectively), compared with patients with a poor histological response (21.4% and 25.6%, respectively). However, these results did not reach statistical significance (P = .07 and P = .1).