CRP and cancer: Patients who were currently treated with adjuvant or palliative anti-cancer treatment had lower tryptophan concentrations (51.9 μmol/L vs. 57.8 μmol/L, p = 0.020) and higher CRP concentrations (0.46 mg/dL vs. 0.24 mg/dL, p = 0.004) as well as higher Kyn/Trp ratios (41.2 vs. 36.4, p = 0.018) compared to patients without current anti-cancer treatment.