Diagnostic values of cytology, cholesterol, carcinoembryonic antigen (CEA), and their combined use in distinguishing between 126 pleural effusions from patients with malignant involvement of the pleura and 121 cases without neoplastic pleural involvement
| Assays | Definition of abnormality | Sensitivity %, (n/N) (95% CI) | Specificity %, (n/N) (95% CI) | Efficacy %, (n/N) (95% CI) |
| Cytology | Malignant cytology* |
69.8 (88/126) (61.0 to 77.7) |
100.0 (121/121) (97.0 to 100.0) |
84.6 (209/247) (79.5 to 88.9) |
| Cholesterol | Raised cholesterol† |
99.2 (125/126) (95.7 to 100.0) |
69.4 (84/121) (60.4 to 77.5) |
84.6 (209/247) (79.5 to 88.9) |
| CEA | Raised CEA‡ |
54.0 (68/126) (44.9 to 62.9) |
89.3 (108/121) (82.3 to 94.2) |
71.3 (176/247) (65.2 to 76.8) |
| Combined cholesterol and CEA | Raised cholesterol†and CEA‡ |
53.2 (67/126) (44.1 to 62.1) |
100.0 (121/121) (97.0 to 100.0) |
76.1 (188/247) (70.3 to 81.3) |
| Cytology and/or combined cholesterol and CEA | Malignant cytology* and/or raised cholesterol† and CEA‡ |
84.1 (106/126) (76.6 to 90.0) |
100.0 (121/121) (97.0 to 100.0) |
91.9 (227/247) (87.8 to 95.0) |
| Cholesterol without inflammation | Raised cholesterol† and non-inflammatory cytology§ |
99.2 (125/126) (95.7 to 100.0) |
98.8 (83/84) (93.5 to 100.0) |
99.0 (208/210) (96.6 to 99.9) |
*Malignant diagnoses: ‘positives’ only, inconclusive cytology incorporated with ‘negatives’.
†Cut-off point for cholesterol: 1.21 mmol/L.
‡Cut-off point for CEA: 5 ng/mL.
§Non-inflammatory cytology: no substantial presence of neutrophils or lymphocytes in effusion sediment.
CI, confidence interval.