Absence of progression, not extent of tumour shrinkage, defines prognosis in soft-tissue sarcoma - An analysis of the EORTC 62012 study of the EORTC STBSG

No association between prognosis and amount of tumour shrinkage was detected. Interestingly, an increase in tumour size by at least 10% correlated with a worse OS, but re-defining PD as a ≥10% increase in tumour size did not translate into a better discrimination of survival outcomes for responders versus stable disease. Disease control rather than tumour response is a valuable end-point in advanced or metastatic STS receiving palliative anthracycline-based chemotherapy, supporting the use of time-to-event end-points in future STS trials.