Trabectedin binds covalently to the DNA minor groove and causes DNA to bend toward the main groove, then trabectedin regulates the transcription of the involved genes in cell proliferation or acts on the mononuclear phagocyte system in tumors, which contributes to its antitumor effects. Several clinical trials confirmed the efficacy of trabectedin for patients with advanced soft tissue sarcoma (STS) although clinically useful biomarkers remained unidentified. This study aimed to identify prognostic factors of trabectedin treatment, especially focusing on the systemic inflammatory, immune response, and nutritional status.

This study included 44 patients with advanced STS treated with trabectedin from January 2018 to August 2022. We evaluated the associations of clinical factors that influence the efficacy of trabectedin treatment with progression-free survival (PFS) and overall survival (OS), focusing on systemic inflammatory, immune response, and nutritional status represented by the absolute lymphocyte count (ALC), neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), lymphocyte-to-monocyte ratio (LMR), systemic inflammation response index (SIRI), prognostic nutrition index (PNI), and C-reactive protein (CRP) using the Kaplan–Meier method and the log–rank test.

ALC, LMR, PNI, NLR, PLR, and SIRI demonstrated no association with PFS. Patients with CRP of ≥0.3 had a significantly shorter PFS than those with CRP of <0.3 (median PFS: 863 vs. 105 days, P = 0.045). PNI of ≥44 (median: 757 days vs. 232 days, P = 0.021) and CRP of <0.3 (median: 877 days vs. 297 days, P = 0.043) were significantly good prognostic factors in terms of OS.

The study results indicate pretreatment PNI and CRP levels as prognostic factors for trabectedin treatment in advanced STS.