Pericardial effusions can be caused by diverse etiologies, including heart-related conditions, kidney failure, trauma, infections, autoimmune diseases, and cancer. This systematic review aimed to assess the role of cytology in identifying the most prevalent cancers related to malignant pericardial effusions (MPEs), the ability of cytology, compared to histology, to detect cancer while evaluating pericardial effusions, and the prognostic impact of MPEs. Four electronic databases were investigated using a predefined algorithm, and specific inclusion and exclusion criteria. We found that the most prevalent primaries associated with MPEs were lung (especially NSCLCs), breast, hematolymphoid, and gastrointestinal cancers. MPEs tended to be hemorrhagic rather than serous or serosanguinous and to occupy larger volumes compared to non-neoplastic effusions. In addition, cytology was shown to exhibit an enhanced ability to detect cancer compared to biopsy in most of the included studies. Lastly, the presence of an MPE was associated with poor prognosis, while survival depended on the specific cancer type detected. Particularly, prognosis was found to be worse when MPEs were caused by lung or gastric cancer, rather than breast or hematolymphoid malignancies. In conclusion, evidence suggests that cytologic evaluation has a significant diagnostic and prognostic impact in patients with MPEs.
Keywords: cancer; cytopathology; diagnosis; lung neoplasms; metastasis; pathology; pericardial fluid; prognosis; sensitivity and specificity; survival analysis.