The significance of cancer antigen 125 in differential diagnosis of petients with pleural effusion

Objective To study the value of cancer antigen 125 (CA125) in the differential diagnosis of patients with pleural effusion.Methods Two hundred and twenty-eight patients with pleural effusion were selected and analyzed retrospectively,including 80 cases with malignant pleural effusion,148 cases with benign pleural effusion (including 52 tuberculous pleural effusion,56 inflammatory pleural effusion and 40 transudative pleural effusion).The levels of CA125 in the pleural effusion and serum were detected and compared.Results The level of CA125 in the pleural effusion of 99.56％(227/228 ) of all the patients was higher than that in the serum.The serum CA125 levels of patients with benign and malignant pleural effusion had significant differences[ (92.19 ± 13.51 ) kU/L vs.( 151.72 ± 23.14) kU/L,P ＜ 0.05 ],but the levels of CA125 in the pleural effusion of benign and malignant patients had no significant difference [(710.38 ±66.03) kU/L vs. (3135.64 ±1404.92) kU/L,P ＞0.05].The levels of serum CA125 in the malignant,tuberculous,inflammatory and transudative pleural effusion were (151.72 ± 23.14),(120.86 ±26.92),(58.09 ± 11.60),(111.22 ±34.19) kU/L,respectively,serum CA125 of malignant pleural effusion was significantly higher than that ofinflammatory pleural effusion (P＜ 0.01 ),but the serum CA125 level of malignant pleural effusion had no significant difference compared with that of tuberculous and transudative pleural effusion (P ＞ 0.05).The levels of CA125 in pleural effusion of malignant,tuberculous,inflammatory and transudative pleural effusion were (3135.64 ± 1404.92),(756.30 ±96.42),(626.86 ± 105.55),(814.41 ± 173.28) kU/L,respectively,the level of malignant pleural effusion had no significant difference compared with that of tuberculous,inflammatory and transudative pleural effusion(P ＞0.05).Conclusions The value of CA125 in the diagnosis of pleural effusion is not very significant when it is used alone.The serum CA125 combined with other tumor markers can improve the diagnosis rate of tumor.When it is applied for clinical aided diagnosis,the non specificity of CA125 should be noticed. Key words: Pleural effusion; CA-125 antigen; Neoplasms