Supplementary Material for: TATI, TAT-2, and CRP as Prognostic Factors in Colorectal Cancer

Objectives: Colorectal cancer is the third most common cancer worldwide, with an obvious need for more accurate prognostics. Previous studies identified C-reactive protein (CRP) as a prognostic serum biomarker for colorectal cancer, whereas the biomarkers tumor-associated trypsin inhibitor (TATI) and tumor-associated trypsin-2 (TAT-2) are less well-known prognostic factors. Therefore, in this study, we aimed to compare the prognostic role of these biomarkers. Materials and Methods: Our cohort consisted of 219 women and 274 men who underwent colorectal cancer surgery at Helsinki University Central Hospital from 1998 through 2005. Serum and plasma samples were collected before surgery, aliquoted, stored at −80°C, and then analyzed using high-sensitivity methods with commercially available time-resolved immunofluorometric assay kits. Results: In univariate analysis, CRP (HR 1.67; 95% confidence interval [CI]: 1.25–2.23; p = 0.001), TATI (HR 1.87; 95% CI: 1.13–3.08; p = 0.014), and TAT-2 (HR 1.52; 95% CI: 1.13–2.06; p = 0.006) were significant prognostic biomarkers across the entire cohort. In subgroup analyses, TATI and TAT-2 represented significant negative prognostic factors among patients older than 66, while patients with left-sided disease, a high serum TAT-2, or a high plasma CRP experienced worse prognosis. None of the biomarkers emerged as important in the disease stage subgroup analysis nor did they serve as independent factors in the multivariate analysis. Conclusions: TATI and TAT-2 as well as CRP significantly, but not independently, served as prognostic factors in our cohort of colorectal cancer patients. Further research is needed to fully understand their clinical role in colorectal cancer.