**5. Glasgow prognostic score in gastric cancer**

Glasgow prognostic score is considered the prognostic milestone of SIR assessment in malignant tumours [91]. It is detected on the basis of the prototypic acute phase protein, C-reactive protein and albumin levels in blood serum. CRP is a non-specific, but sensitive marker of systemic inflammatory response, produced as a response to pro-inflammatory cytokines including interleukins IL-1 and IL-6 as well as tumour necrosis factor TNF. Hypoalbuminemia can be caused by malnutrition and cancer cachexia or by systemic inflammation [68]. GPS includes both estimates of elevated acute phase response and malnutrition, resulting in considerable sensitivity [68]. Later, two alterations of Glasgow prognostic score have been developed—the modified GPS and high-sensitivity GPS. In the modified GPS, albumin level influences the score only if CRP is increased [31]. However, the definitions also show variability between authors [92]. High-sensitivity GPS differs from the original GPS by lower cut-off level for CRP [93]. The definitions of GPS and its modifications are summarised in **Table 4**.
