2024 Volume 63 Issue 1 Pages 19-24
Background : Lung epithelioid hemangioendothelioma (EHE) is a rare vascular neoplasm, and diagnosis by cytology is often challenging. We report a case of EHE diagnosed by endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) biopsy. We also reviewed the cytology slides and found metachromatic mucous material by May-Giemsa staining.
Case : A 50s-year-old woman underwent EBUS-TBNA of a left hilar mass. Cytologic examination showed loosely cohesive clusters of epithelioid cells containing irregular nuclei with nucleoli and intracytoplasmic vacuoles. These cytologic findings suggested adenocarcinoma, however, histopathology revealed positive results for endothelial markers, and the final pathological diagnosis was EHE. We reevaluated the cytological findings and found metachromatic myxoid material by May-Giemsa staining of the sections.
Conclusion : The cytological features of this case were similar to those of adenocarcinoma, making differentiation between the two difficult. Detection of metachromatic interstitial mucus is useful for the diagnosis of EHE.
