Role of cancer antigen-125 from pleural & ascitic fluid samples in non malignant conditions.

BACKGROUND & OBJECTIVE CA-125, an ovarian tumor marker is known to increase in non malignant conditions such as tubercular and non tubercular pleuritis and ascites. We undertook this study to evaluate non-specific rise in CA-125 levels in conditions associated with pleural effusion and ascites and also to understand the mechanism of its secretion. METHODS CA-125 levels in 38 pleural and 46 ascitic fluid samples from non malignant cases and 10 blood samples from pulmonary tuberculosis cases were estimated by ELISA. The ascitic fluid samples were collected from cases of bacterial peritonitis, tuberculosis, hepatitis, cirrhosis of other aetiology and pleural fluid samples were from cases of tubercular, pyogenic, cardiomegaly and other conditions. RESULTS Both ascitic and pleural fluid samples (transudative and exudative) showed elevated CA- 125 levels. The CA-125 levels were significantly higher in ascitic fluid samples than in pleural fluid samples. INTERPRETATION & CONCLUSION Our findings showed that elevated levels of CA-125 in pleural and ascitic fluid could be because of varied aetiologies which need to be ruled out before considering malignancy. Peritoneum has a greater capacity to secrete CA-125 than the pleural epithelium and the secretion occurs following inflammation or mechanical distress. Pulmonary tuberculosis as a closed lesion without involvement of pleural epithelium does not evoke high CA-125 release.