Prognostic significance of TP53 tumor suppressor gene expression and mutations in human osteosarcoma: a meta-analysis. Various studies examining the relationship between tumor suppressor protein TP53 overexpression and/or TP53 gene mutations and the response to chemotherapy and clinical outcome in patients with osteosarcoma have yielded inconclusive results. The purpose of the current study was to evaluate the relation of TP53 status with response to chemotherapy and/or clinical outcome in osteosarcoma.We conducted a meta-analysis of 16 studies (n=499 patients) that evaluated the correlation between TP53 status and histologic response to chemotherapy and 2-year survival. Data were synthesized in summary receiver operating characteristic curves and with summary likelihood ratios (LRs) and risk ratios.The quantitative synthesis showed that TP53 status is not a prognostic factor for the response to chemotherapy. The positive LR was 1.21 (95% confidence interval, 0.86-1.71), and the negative LR was 0.91 (95% confidence interval, 0.77-1.07). There was no significant between-study heterogeneity. TP53-positive status tended to be associated with a worse 2-year survival, but the overall results were not formally statistically significant. The association was formally significant in studies that clearly stated that measurements were blinded to outcomes (risk ratio, 2.05; 95% confidence interval, 1.23-3.44), and in studies using reverse transcription-PCR for evaluating TP53 alterations (risk ratio, 1.76; 95% confidence interval, 1.07-2.91).TP53 status is not associated with the histologic response to chemotherapy in patients with osteosarcoma, whereas TP53 gene alterations may be associated with decreased survival.