Significance of CEA Dynamics and Systemic Inflammatory Markers in HER2-Positive Metastatic Colorectal Cancer Patients Undergoing First-Line Chemotherapy: A Real-World Cohort Study. - Ozkerim U; Kinikoglu O; Oksuz S; Isik D; Altintas YE; Yildirim S; Akdag G; Surmeli H; Odabas H; Basoglu T; Turan N (Medicina (Kaunas, Lithuania), 2026)