Clinical significance of serum cancer antigen 125 in patients with pleural effusions

Abstract

Objective To investigate the change of serum cancer antigen(CA) 125 in patients with pleural effusion.Methods One hundred and twenty-eight patients with pleural effusion were admitted to the Naval General Hospital of People's Liberation Army from January 2010 to September 2012 were selected as our subjects.The level of serum CA125 was measured.The difference of serum CA125 positive rate and level were compared according to gender,pleural effusion nature,quantity and pleural effusion chest area; And the difference of patients with malignant pleural effusion tuberculosis,inflammatory,exudative pleural effusion based on above indicators.The correlation between serum CA125 level and pleural effusion depth were analyzed.Results The positive proportions of CA125 were 83.3％ (35/42) and 76.7 ％ (66/88) of patients with malignant and benign effusion respectively,and there was no significant difference (x2 =0.74,P ＞ 0.05).The serum CA125 level of patients with malignant pleural effusion was significantly higher than benign ones ((177.8 ± 31.4) U/ml vs.(110.6 ± 13.6) U/ml,t =31.24,P ＜ 0.05).There were no significant difference in the positive proportion of serum CA125 between malignant,tuberculous,inflammatory and transudative pleural effusion(75.8％ (25/33),70.0％ (20/29),87.5％ (21/24) and 83.3％ (35/42),P ＞ 0.05).Serum CA125 levels of patients with malignant pleural effusion were significantly higher than that with inflammatory ((177.8 ± 31.4) U/ml vs.(72.5 ± 12.8) U/ml,P ＜ 0.05),but the differences were not significant among malignant,tuberculous and transudative pleural effusion group((140.6 ± 28.2) U/ml,(154.3 ± 30.5) U/ml,P ＞ 0.05).The serum CA125 levels of patients with small,moderate and large effusions were (56.4 ± 18.2) U/ml,(120.2 ± 24.5) U/ml and (185.5 ± 34.6) U/ml respectively,and the difference among these groups were significant(F =296.03,P ＜ 0.05).Serum CA125 levels was positively correlated with pleural fluid depth (r =0.56,P ＜0.01).Different gender,pleural effusion parts serum CA125 positive rate and the different levels were not statistically significant (P ＞ 0.05).Conclusion Serum CA125 increased in patients with benign and malignant pleural effusion,and serum CA125 was not severed as the diagnosis biomarker in differentiating benign and malignant pleural effusion.Serum CA125 levels is helpful in monitoring the change of pleural fluid size due to the relation with depth of pleural fluid. Key words: Pleural effusion; Cancer antigen 125 ; Serum