Table 2.

Aetiology and diagnosis of the MPE (n = 98), median levels of CEA in serum and pleural fluid, and the median ratio of CEA in pleural fluid/serum.

	n (%)	CEA serum; ng/ml, median	CEA pleural fluid; ng/ml, median	Ratio pleural fluid/ serum, median
MPE associated with lung cancer, n (%)
Adenocarcinoma	62 (63.3)	7.20	82.50	4.2
Small-cell lung cancer	13 (13.3)	7.50	18.30	2.1
Squamous-cell carcinoma	6 (6.1)	3.10	10.55	2.7
Large-cell lung carcinoma	2 (2.0)	181.50	94.00	0.8
MPE associated with other carcinomas, n (%)
Mammary carcinoma	8 (8.2)	9.50	13.00	1.6
Endometrial carcinoma	2 (2.0)	2.45	4.95	1.5
Carcinoma of unknown primary	1 (1.0)	4.00	520.00	130.0
Renal-cell carcinoma	1 (1.0)	1.60	1.80	1.1
Ovarian carcinoma	1 (1.0)	0.60	0.40	0.7
Salivary gland carcinoma	1 (1.0)	7.40	5.10	0.7
Prostate carcinoma	1 (1.0)	3.00	5.90	2.0

CEA, carcinoembryonic antigen; MPE, malignant pleural effusion.