Flow cytometry in the detection of circulating tumor cells in neoplastic effusions

Purpose: Despite its limitations, the cytology of body fluids is widely used in diagnosing neoplastic cells. Flow cytometry detects and identifles individual cells, enabling the detection of circulating tumor cells and facilitating diagnosis. This study compared the diagnostic utility of flow cytometry and cytology for detecting cancer cells in peritoneal and pleural fluids.Methodology: We used flow cytometry and cytology to examine 119 pleural and peritoneal effusions received for routine screening. Antibodies against clusters of differentiation 45 (CD45), 14 (CD14), and Epithelial cell adhesion molecule (EpCAM) were used to detect malignant cells. Based on combined clinical and diagnostic information, 37 fluid specimens were malignant, and 77 were benign.Results: Flow cytometry correctly identifled 34 cancers, while cytology identifled 26 cancers (sensitivity 91.89 % vs. 70.27, respectively). Both methods had equal speciflcity (98.7 %). At a cut-off of > 0.29 % EpCAM(+) cells to all cells in the samples, flow cytometry accurately detected cancer cells, achieving 89.2 % sensitivity, 90.9 % speciflcity, and an AUC of 0.959 (p < 0.001).Conclusion: Flow cytometry improves the detection of epithelial cancer cells in peritoneal and pleural fluids compared to conventional cytology. Due to similar speciflcity and higher sensitivity, flow cytometry offers a promising alternative to cytology for patient screening.

Automated summary

Flow cytometry improves the detection of epithelial cancer cells in peritoneal and pleural fluids compared to conventional cytology. Due to similar speciflcity and higher sensitivity, flow cytometry offers a promising alternative to cytology for patient screening.