The staging can be used as one of the prognostic factors providing a clinical picture of the patient in the future in colorectal cancer patient. In addition, carcinoembryonic antigen (CEA) as tumor markers can determine the commonly used diagnosis and prognosis of colorectal cancer. Objective: The aims study was to investigate the relationship of the staging and carcinoembryonic antigen serum levels in colorectal cancer patients. Methods. This was an analytical study with a cross-sectional design. The sample used was colorectal cancer patients at H. Adam Malik General Hospital, Medan from January 2016 to December 2018. As many as 52 subject study who met the inclusion and exclusion criteria. The Kruskal-Wallis test was used to determine relationship between staging and CEA serum levels. Results: The median value of carcinoembryonic antigen levels in Stage I, II, III, and IV group was (2.74 ng/ml vs 6.16 ng/ml vs 2.52 ng/ml, vs 26.87 ng/ml; p=0.003) respectively. Conclusion: There was relationship between staging and carcinoembryonic antigen serum levels in colorectal cancer patient

Histopathological grading, which represents the degree of histopathological differentiation, is often used as one of the factors to determine the prognosis of colorectal cancer. However, this grading cannot comprehensively present the clinical features of the disease. Carcinoembryonic antigen (CEA), as a tumor marker tested in the laboratory, is commonly used to determine the diagnosis and prognosis of colorectal cancer. The purpose of this study was to determine differences in CEA serum levels based on the cellular differentiation of colorectal cancer. This was a cross-sectional analytical study on medical records of colorectal cancer patients who were admitted to H. Adam Malik General Hospital Medan, Indonesia from January 2016 to December 2018. As many as 52 medical records of colorectal cancer patients who met the inclusion and exclusion criteria were included in this study. These patients were then divided into three groups based on the histopathological grade: well-differentiated, moderately differentiated, and poorly-differentiated. The Kruskal-Wallis test was then used to compare the CEA levels in these different histopathological grades. Results show that the CEA serum level was different in colorectal cancer patients with different histopathological grades (p=0.020). The CEA level was significantly higher in the poorly-differentiated group than the well-differentiated (p=0.044) and moderately differentiated (p=0.015) groups. Hence, the CEA level of colorectal cancer patients with poorly-differentiated grade is the highest when compared to other grades.