Serotonin: Is it a marker for the diagnosis of hepatocellular carcinoma in cirrhotic patients?
Hepatocellular carcinoma (HCC) is the third most frequent cause of cancer mortality among men worldwide. Serotonin is a biogenic amine, ligand of a family of 5-HT receptors that reflect the diversity of serotonergic actions. Majority of serotonin in body (90%) is synthesized by enterochromaffin cells of the gastrointestinal tract and is exported to various sites. Serotonin regulates blood flow and vascular tone at portal and sinusoidal levels, serotonin acts as a mitogen for hepatocytes and promotes liver regeneration. 5HT emerges as a mediator of different pathological conditions (double edged sword). It contributes to liver fibrosis, mediates oxidative stress in nonalcoholic steatotic hepatitis and aggravates viral hepatitis, these conditions are involved in tumourigenesis of hepatocellular carcinoma (HCC). Impaired metabolic function in liver cirrhosis and slow uptake and storage of serotonin by the platelets is a sequelae of kinetic change of serotonin transport mechanisms or abnormal serotonin release from dense granules of activated platelets is a condition defined as ‘‘platelet exhaustion’’, contributes to elevated plasma serotonin which may facilitate tumour growth of primary liver hepatocellular carcinoma.
Aim of this work: To determine whether serotonin is a marker for the diagnosis of hepatocellular carcinoma in cirrhotic patients.
Methods: Patients were classified into two groups; 45 patients with cirrhosis only and 30 patients with cirrhosis and HCC. Ten healthy subjects were taken as controls. Patients underwent; full history taking, clinical examination, and abdominal ultrasonography. Laboratory methods include SGOT, SGPT, GGT, bilirubin, alkaline phosphatase, total proteins, albumin, CBC, prothrombin, INR, APRI score, Child-pugh score, MELD score, AFP and serum serotonin.
Results: Plasma serotonin was significantly higher in the patients group with cirrhosis with a median level of 119.4 ng/ml than in the control group which showed a median value of 51.5 ng/ml p< 0.001. A significance difference was also seen between cirrhosis and the HCC group with a median value of 478.35 ng/ml than the control group and a cirrhosis group with p< 0.001was found.
Conclusion: Plasma serotonin level was significantly higher in patients with cirrhosis and HCC than in those with cirrhosis only and it was involved in the tumourigenesis of hepatocellular carcinoma.
Keywords: Serotonin; AFP; HCC