SPP1 and neoplasm: Moreover, in combined uni- and multivariate Cox regression analysis including markers of liver and kidney function (aspartate transaminase (AST) and creatinine), systemic inflammation (leucocyte and CRP), established CRC tumour markers (CEA) as well as clinical (ECOG PS, BMI) and pathological (largest size of CRLM, primary CRC tumour localisation) parameters, circulating levels of osteopontin stood out as an independent prognostic marker (HR 3.083 [1.054–9.020], p = 0.040, Table 2).