A Case of Epithelioid Angiosarcoma Diagnosed From Gross Examination of a Pulmonary Tumor Utilizing Imprint Cytology and Immunocytochemistry

Abstract

ABSTRACT Background Angiosarcoma, a very rare malignant tumor constituting 2%–4% of soft tissue sarcomas, manifest in diverse organs including skin, soft tissues, and bones. Histologically, angiosarcoma presents a wide range of morphologies, with epithelioid angiosarcoma (EAS) resemblance to carcinoma. The difficulty arises from the shared epithelial‐like morphology and expression of epithelial markers in immunohistochemistry. Case This study reports a case where EAS diagnosis was achieved through a combination of gross findings in a lung resection sample, imprint cytology, and immunocytochemistry. Imprint cytology revealed clusters of epithelioid cells, while immunocytochemistry showed positive results for CD31, ERG, Fli‐1, and AE1/AE3, proving instrumental in diagnosing EAS. The described immunocytochemical protocol facilitates prompt diagnosis exclusively through cytology samples. Conclusion This report emphasizes the potential for diagnosing EAS using cytological specimens, which is especially useful in cases where obtaining tissue samples proves challenging.

Keywords

• angiosarcoma
• cytopathology
• epithelioid
• immunocytochemistry
• touch‐imprint