CRP and esophageal cancer: On the other hand, though other systemic inflammatory parameters, such as PLR, neutrophil-lymphocyte ratio (NLR) and C-reactive protein (CRP) were documented to be associated with poor prognosis in cancer patients, they are also found to be limited in several aspects.[38–42] For example, many studies have found that PLR could not act as a significant predictor of OS in various cancers.[43–45] Additionally, though CRP has been identified to be related to the progression of esophageal cancer,[42] the test of CRP is not routinely available in most hospitals.