Predictive role of FAS for trabectedin in second lines of advanced soft tissue sarcoma (ASTS): A Spanish group for research on sarcoma (GEIS) study.

11071Background: There are currently several second-line options for the treatment of ASTS as gemcitabine combinations, trabectedin, pazopanib, eribulin or olaratumab plus doxorubicin in cases where anthracyclins are still possible. There is an unmet need for predictive biomarkers which hinders the rational selection of the best sequence in second line. We already published the prognostic value of FAS in first line of ASTS while this study analyzes its predictive role in different second line schemes. Methods: Most relevant selection criteria for this study were having received trabectedin in 2nd line or beyond for ASTS, progressive disease after at least one previous line for ASTS and signed CI. A TMA was set up for FAS staining (Cell Signaling) with blocks from diagnostic time. Two expert blinded pathologists reviewed and classified the cases as negative, weak or strong. Kaplan–Meier estimations were used for time-to-event variables and the log-rank test was used to compare groups. Results: A series of ...