Can the scoring used in liver diseases be used to differentiate malignant and benign cholestasis?

Bacground and aim: Chronic biliary tract diseases impair hepatocyte functions by causing longer exposure to bilirubin in hepatocytes and toxins excreted from the liver. In addition, there are publications suggesting that biliary tract malignancies, like primary malignancies of the liver, are also characterized by fibrosis. In the light of this information, it can be thought that cholestatic diseases that cause chronic and malignant bile duct obstruction worsen liver functions and increase liver fibrosis than diseases that cause acute and benign biliary tract obstruction. In our study, we aimed to investigate which scoring systems used in liver diseases (R-factor, the model for end-stage liver disease-natrium, albumin-bilirubin score, alkaline phosphatase-to-platelet ratio, aspartate aminotransferase to platelet ratio index, fibrosis-4 score and gamma-glutamyl transpeptidase-to-platelet ratio) could be used as an auxiliary method in the diagnosis of malignant cholestasis. Material and Method: The files of patients who were diagnosed with obstructive cholestasis in Ondokuz Mayıs University Faculty of Medicine, Gastroenterology Clinic between July 2017 and July 2021 were reviewed retrospectively. Patients diagnosed with acute and benign cholestasis were classified as Group 1, and patients with chronic and malignant cholestasis were classified as Group 2. Using the laboratory values of the patients at the time of first application; R-factor, the model for end-stage liver disease-natrium, albumin-bilirubin score, alkaline phosphatase-to-platelet ratio, aspartate aminotransferase to platelet ratio index, fibrosis-4 score and gamma-glutamyl transpeptidase-to-platelet ratio scores were calculated, and the relationship between their diagnosis and their scores at the time of diagnosis was evaluated. Results: A total of 202 patients, 116 male (57.4%) and 86 female (42.6%), were included in the study. There were 92 (45.5%) patients in Group 1 and 110 (54.5%) patients in Group 2. There was no significant difference between Group 1 and Group 2 in terms of demographic characteristics. Common diseases were cholangitis, choledocholithiasis, biliary sludge and biliary pancreatitis in Group 1, and pancreatic head carcinoma in Group 2, respectively. Among the laboratory parameters, alkaline phosphatase, total and direct bilirubin were the most important tests indicating malignancy (p < 0.001). Among the liver disease scores; R-factor (p < 0.001), the model for end-stage liver disease-natrium (p < 0.001) and albumin-bilirubin score (p = 0.023) were significant in favor of Group 2, while alkaline phosphatase-to-platelet ratio (p < 0.001), aspartate aminotransferase to platelet ratio index (p < 0.001) and fibrosis-4 score (p < 0.001) were significant in favor of Group 1, but there was no significant difference between the two groups in terms of gamma-glutamyl transpeptidase-to-platelet ratio (p = 0.242). The final diagnosis of the patients in Group 1 was mostly made by ultrasonography (p < 0.001), whereas the patients in Group 2 were diagnosed with computed tomography (p < 0.001). Conclusion: Our study showed that R-factor, the model for end-stage liver disease-natrium and albumin-bilirubin score could be used as an auxiliary method in the diagnosis of malignant cholestatic diseases. Alkaline phosphatase-to-platelet ratio, aspartate aminotransferase to platelet ratio index and fibrosis-4 score could be used as an auxiliary method in the diagnosis of benign cholestatic diseases. However, gamma-glutamyl transpeptidase-to-platelet ratio could not be used in this distinction. Such predictive scores could be interpreted together with the anamnesis and examination findings, making it easier for patients to be examined and treated more quickly.