Cytology of Pleural, Pericardial and Peritoneal Cavity Effusions - Effusions Mesothelioma

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Figure 22
Pleural effusion Mesothelioma. 10X

Figure 23
Pleural effusion Mesothelioma. 20X

Figure 24
Pleural effusion Mesothelioma. 40X

Figures 22-24:
Various magnifications show “cannon-ball” masses of tumor cells. The key to diagnosing mesothelioma is not identifying a second malignant cell population. Final determination may require immunocytochemistry or a cell block with immunohistochemistry, electron microscopy, or other specialized techniques.

Figure 25
Pleural effusion Mesothelioma. 60X

Individual malignant mesothelial cells exhibit a rim of ruffled, less dense cytoplasm (ectoplasm), surrounding dense cytoplasm around the nucleus (endoplasm).

Figure 26
Pleural effusion Mesothelioma. 20X

Tumor cells may be seen in a background of blood and proteinaceous debris. Groups of more than 12 cells may be a feature of malignancy.

Figure 27
Pleural effusion Mesothelioma. 60X

At higher magnification, the high N/C ratio with variability in nuclear size and occasional multi-nucleation confirm the malignant nature of these cells. Differential diagnoses include adenocarcinoma and mesothelioma. Fine microscopic features of peripheral cell membranes and intercellular windows may suggest mesothelioma.

Figure 28
Pleural effusion Mesothelioma. 60X