Inflammation and cancer: What a surgical oncologist should know

Chronic inflammation is an aberrantly prolonged form of a protective response to a loss of tissue homeostasis and it is involved in several steps of the carcinogenesis process. As a result, many cancers are inflammation-related. The systemic inflammatory response is associated with survival in advanced and localized cancers. Two categories of scores have been proposed to monitor the systemic inflammatory response, those derived from protein measurement and those based on counting inflammatory cells. This review aims to provide a critical appraisal of these 2 categories of surrogate markers. The 3 scale modified Glasgow prognostic score (mGPS) is based on the combination of C-reactive protein and albumin and is graded 0 to 2. It has been validated worldwide showing an independent prognostic value in patients with cancer in a variety of tumour types and tumour stages. Leukocytes-based scores are mainly neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR) and lymphocyte-to-monocyte ratio (LMR). Elevated NLR and/or PLR and lower LMR seem to be associated with decreased survival, but the studies about these markers are very heterogeneous. The main limit is the variety of thresholds used to dichotomize patients, so that reproducibility and reliability of leukocytes-based scores can be questioned. Hence, there is no sufficient evidence to support their use in clinical practice. Comprehensive management of patients with operable and advanced cancer should integrate the host systemic inflammatory response by calculating the mGPS. It could be a helpful tool to tailor patients' management.