From the Guidelines
Lung cancer, specifically adenocarcinoma, has the highest likelihood of a positive pleural aspirate for cytology.
Key Factors Influencing Diagnostic Yield
- The diagnostic yield of pleural fluid cytology varies depending on tumor type, with adenocarcinoma having the highest yield compared to mesothelioma 1.
- The mean diagnostic sensitivity of pleural fluid cytology for malignancy is between 49% and 91%, with maximal yield from two separate samples 1.
- Cytology has the highest diagnostic yield for adenocarcinoma, with a sensitivity range of 62-90% 1.
Importance of Sample Preparation and Ancillary Tests
- Sample preparation, such as submitting more than 50 mL of pleural fluid and using both a cell block and a smear, can improve the diagnostic yield 1.
- Ancillary tests, such as immunohistochemical staining and genetic testing, can aid in differentiating mesothelioma from adenocarcinoma and other malignancies 1.
Clinical Implications
- A positive pleural aspirate for cytology can alter the stage of the cancer and the treatment of the patient 1.
- The diagnostic yield of cytology for mesothelioma is lower, ranging from 16% to 30%, and often requires tissue confirmation 1.
From the Research
Cancers with High Likelihood of Positive Pleural Aspirate for Cytology
- Lung adenocarcinoma has a high sensitivity for pleural fluid cytology, with a sensitivity of 83.6% 2 and 87.9% 3
- Ovarian cancer also has a high sensitivity, with a sensitivity of 85.2% 2
- Breast cancer has a moderate to high sensitivity, with a sensitivity of 65.3% 2 and 91.3% 4
- Adenocarcinomas have a high sensitivity, with a sensitivity of 87.9% 3
Cancers with Low Likelihood of Positive Pleural Aspirate for Cytology
- Mesothelioma has a low sensitivity, with a sensitivity of 28.9% 2, 45.5% 3, and 33.3% 4
- Lung squamous cell carcinoma has a low sensitivity, with a sensitivity of 24.2% 2
Factors Affecting Pleural Fluid Cytology Sensitivity
- Tumor type is an important determinant of pleural fluid cytology diagnostic yield 2, 3, 4
- Cloudy appearance of pleural fluid and yellow/gold pleural fluid can reduce the odds of false negative pleural cytology 4
- Pleural thickening on computed tomography scan can increase the risk of false negative cytology 4