(P 125) EFFECTIVENESS OF PERIPHERAL BLOOD IMMUNE-RELATED MARKERS IN SELECTING NOVEL THERAPEUTIC AGENTS FOR ADVANCED SOFT TISSUE SARCOMA

Objective: Pazopanib, trabectedin, and eribulin are administered for the treatment of soft tissue sarcomas (STSs); however, because there are no head-to-head comparative trials among these three agents or good biomarkers indicating the effectiveness of each treatment, a consensus on which agent should be preferentially used has not been reached. Peripheral immune-related markers such as absolute lymphocyte count (ALC), neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and lymphocyte-to-monocyte ratio (LMR) have been attracting attention as factors that predict cancer prognosis. This study assessed whether peripheral immune-related markers served as a useful reference when selecting pazopanib, trabectedin, or eribulin.

Methods: This study included 63 patients who were administered pazopanib, trabectedin, or eribulin for advanced STSs between March 2015 and December 2020. Patients were divided into three groups based on the first drug administered among these three drugs. The cutoff values were set as follows: 1,500 for ALC, 3 for NLR, 200 for PLR, and 3 for LMR based on previous studies. Differences in overall survival (OS) or progression-free survival (PFS) among the three groups were analyzed.

Results: OS and PFS showed no significant differences among the drugs administered first (Figure 1). For patients with low NLR, the OS of patients administered pazopanib as the first choice was shorter than the others (median = 520 days [95% CI = 148–602] for pazopanib; 838 days [95% CI = 587–1198] for other treatments; p = 0.0005) (Figure 2a). In the low PLR subgroup, the OS of the patients administered eribulin for the first choice was longer than that of the others (median = 1198 days [95% CI = 587–1198] for eribulin; 579 days [95% CI = 394–838] for other treatments; p = 0.036) (Figure 2b). PFS was not significantly different based on the first administered drugs in each subgroup.

Conclusion: This study demonstrated that eribulin or trabectedin for patients with low NLR and eribulin for patients with low PLR were associated with longer OS compared to the other drugs, whereas the OS differences were not statistically significant in the analysis of the whole patient cohort without grouping by peripheral immune-related markers. This study generated an interesting hypothesis on the usefulness of peripheral immune-related markers, which warranted further study in a larger, prospective trial. When selecting either pazopanib, trabectedin, or eribulin for advanced STSs, NLR and PLR served as useful references that should be considered clinically.