Background: Systemic inflammation has been implicated in cancer development and progression. The aim of the present study was to evaluate whether pre-operative systemic inflammatory markers can predict outcomes in bone and soft tissue sarcomas.
Methods: Relevant literature was mainly identified using Pubmed, EMBASE and CNKI. Patients' clinical characteristics, overall survival (OS), disease/relapse free survival (DFS/RFS) with high-level CRP or neutrophils to lymphocytes ratio (NLR) were extracted. The statistics extracted from Kaplan-Meier survival curves with log-rank p value were calculated with methods developed by Parmar, Williamson, and Tierney; multivariate Cox hazard regression analysis data were used directly in STATA 10.0. Pooled hazard ratio (HR) and 95% CI were calculated to evaluate the prognostic role of these systemic inflammatory markers (CRP/NLR).
Results: After full text review, 11 articles containing 1809 patients were identified as eligible articles. The meta-analysis for survival outcome showed significant prognostic value of systemic inflammatory markers including CRP and NLR in pre-operative blood. The combined HRs (95% CI) for five year overall survival (OS) and disease/recurrence free survival (DFS/RFS) were 2.54 [2.04, 3.16] and 2.28 [1.72, 3.04]. Specifically, higher NLR was associated with decreased 5-year OS (HR 3.75, 95% CI 1.24 to 11.37) and 3 year RFS/DFS (HR 2.43, 95% CI 0.84 to 7.05). Besides, the pooled HR showed a higher risk of 5-year disease progression (HR 2.55, 95% CI 1.60 to 4.08, I2 = 52%) and lower 5-year OS (HR 2.50, 95% CI 2.00 to 3.12, I2 = 0%) in sarcoma patients with high CRP level. We then grouped the meta-analysis by patient source (Asian and non-Asian), tumor stage (I/II or III/IV) and grade (high or low), respectively. All the subgroup analysis showed significant prognostic role in survival condition. The CRP/NLR levels are also found closely related with patient age, tumor stage and size.
Conclusion: Higher level of pre-operative CRP and NLR demonstrated a significantly higher risk of recurrence and overall decreased survival rates in sarcomas.
Keywords: CRP; meta-analysis; prognostic factor; sarcoma.