Background: Elevations in inflammatory biomarkers, including neutrophil-to-lymphocyte ratio (NLR) or platelet-to-lymphocyte ratio (PLR), are reportedly associated with decreased overall survival (OS) or recurrence-free survival (RFS) in patients with numerous cancers. A large multicenter sarcoma data set was used to determine if elevated NLR or PLR was associated with worse survival and can guide treatment selection. Materials and methods: A total of 409 patients with a primary retroperitoneal sarcoma (n = 268) or truncal (n = 141) sarcoma from 2000 to 2015 were analyzed using the US Sarcoma Collaboration database. Binary NLR and PLR values were developed using receiver operating characteristic curves. Kaplan-Meier model and Cox proportional hazards model identified predictors of decreased OS and RFS. Point biserial analyses were used to correlate binary and continuous data. Results: Neither elevated NLR nor PLR was predictive of decreased OS or RFS. These findings persisted despite exclusion of comorbid inflammatory conditions. Further, NLR and PLR were not correlated with tumor grade. In multivariate models, decreased RFS was associated with tumor factors (e.g., positive margins, tumor grade, tumor size, necrosis, positive nodes); decreased OS was associated with histologic subtype, male gender, and nodal involvement. Conclusions: Although several small studies have suggested that elevated NLR and PLR are associated with decreased survival in patients with abdominal or truncal sarcoma, this large multicenter study demonstrates no association with decreased OS, decreased RFS, or tumor grade. Rather, survival outcomes are best predicted using previously established tumoral factors.