Comparison of parameters used in differential diagnosis of malignancy related ascites and nonmalignant ascites

SUMMARY: Various parameters have been proposed to date in the differential diagnosis of malignancy-related ascites (MRA) and non-malignancy-related ascites (NMRA). However, none of them has sufficient sensitivity and specificity yet. In order to examine the role of serum-acid albumin gradient (SAAG), acidic fluid alpha1-antitrypsin (AS-AAT) level and DNA analysis by flow cytometry (FCM) in the differential diagnosis of malignant acid, 14 patients with MRA and 14 patients with NMRA of various etiologies were included in the study. Of 28 patients, 19 were female and 9 were male, with a mean age of 56.2 (23-84). The mean SAAG and AS-AAT levels in MRA were 0.95 ±0.76 and 272.66±134.55, respectively. These values were significantly higher than those in NMRA (p= 0.0123 and p= 0.0088). The mean SAAG and AS-AAT levels in NMA were 1.90±0.96 and 144.07±88.77, respectively. In distinguishing MRA from NMRA, the sensitivity of SAAG alone was 71%, specificity 85%, positive predictive value 83%; AS-AAT was found to be 78%, 50% and 60%, respectively. When those with SAAG value <1.1 and AS-AAT level >120 mg/dl are considered together, the sensitivity (71%) does not change; specificity increased to 92% and positive predictive value to 90%; also, both parameters had superiority in revealing MRA in cytology negative cases. When cytology was added to this combination, the sensitivity reached 85%. Since DNA analysis with FCM was found to have a low sensitivity of 14% in distinguishing MRA in this study, its use for diagnostic purposes is not recommended. In conclusion, determination of AS-AAT level in the second step in patients with low albumin gradient along with cytology seems to be an effective method for the diagnosis of MRA.