Biomarkers of malignant ascites—a myth or reality

Abstract

Ascitic fluid aspirate cytology, although reasonably specific is not a good screening tool for malignant ascites due to poor sensitivity. Simple test(s) on ascitic fluid or serum which can help differentiate between benign and malignant causes of ascites will be a boon. Ascitic fluid lactate dehydrogenase, cholesterol, and ferritin are the candidate markers evaluated in this study. Ascitic fluid cytology was done on 30 patients of malignant ascites. The modalities used for diagnosing malignant ascites were positive peritoneal biopsy or CT scan evidence of hepatic metastases. Ascitic fluid biochemistry was done in all these 30 patients as well as 30 cases of non-malignant ascites. The parameters analysed were cholesterol, lactate dehydrogenase, and ferritin. The biochemical parameters were estimated in serum as well. Cytology had a sensitivity of 40% for the diagnosis of malignant ascites. Ascitic fluid cholesterol, lactate dehydrogenase, and ferritin had sensitivities of 70%, 74%, and 100%, respectively. Serum cholesterol, lactate dehydrogenase, and ferritin had sensitivities of 57%, and 91%, respectively. Hence, these biochemical markers in ascitic fluid as well as serum can be good screening tools for the diagnosis of malignant ascites.