Diagnostic Potential of Circulating CXCL13, CXCL14, and CXCL16 in Colorectal Cancer: A Preliminary Case-Control Study

Introduction: Epidemiological trends indicate that the global colorectal cancer (CRC) mortality will surpass 2.2 million deaths annually by the year 2050; therefore, the identification of novel circulating indicators that may support CRC diagnosis remains an important area of research. Objectives: The diagnostic relevance of circulating chemokines in CRC remains insufficiently understood. This study aimed to evaluate the diagnostic potential of selected serum C-X-C motif chemokines, CXCL13, CXCL14, and CXCL16, and to compare their diagnostic utility with CEA. Patients and Methods: This study included 62 individuals: 42 patients with CRC and 20 healthy volunteers. Serum chemokines levels were measured using a multiplex bead-based immunoassay (Luminex), and CEA levels via chemiluminescent microparticle immunoassay (CMIA). Results: Significant differences between patients with CRC and healthy controls were observed for serum CXCL13 concentrations. Spearman's analysis revealed a significant negative correlation between CXCL13 and CXCL14. CXCL14 showed the highest diagnostic sensitivity among the chemokines, similar to CEA, while combining CXCL13 or CXCL14 with CEA further increased sensitivity. CXCL13 showed the highest positive predictive value (PPV) among all tested proteins, while its negative predictive value (NPV) and diagnostic accuracy (ACC) exceeded those of CXCL14 and CXCL16. CXCL13 demonstrated the highest AUC among the investigated chemokines and remained independently associated with CRC status in multivariable analysis. CXCL13 combined with CEA yielded the numerically highest overall AUC, although the improvement over CEA alone was not statistically significant. Conclusions: CXCL13 serves as a valuable complementary biomarker, providing crucial additive insights that might augment diagnostic frameworks of patients with CRC. These findings support further evaluation of chemokines as potential adjuncts to established diagnostic biomarkers in larger, independent screening-like study cohorts.