Pulmonary metastasis of a postradiation breast epithelioid angiosarcoma mimicking adenocarcinoma : A case report

Background Epithelioid angiosarcoma (EAS) is a mesembymal neoplasm that may appear indistinguishable from carcinoma, melanoma and other tumors with epithelioid/epithelial differentiation. We repart a case of metastain postradiation EAS to the lungs that was mistaken for adenocarcinoma. Case A 45-year-old women who received radiotherapy for ductal carcinoma in situ (DCIS) 5 years preciously bad a Iocal recurence a year carlier and recent development of bilateral small pulmonary nodules. Fine needle aspiration biopsy of the lung lesions showed round to oval tumor cells with amphophlic cytoplasm. An interpreta tion of adenocarcinoma was rendered during assessment for specimen adequacy. The original brcast tumor was typical of cribriform DCIS. Review of the recurrent breast tumor (initially reported as DCIS) and a prior wedge resection of the lung nodules (reporred as EAS) showed an cpithelial-appearing tumor exbihiting an endotbelial immunophenotype (CD31+, CD34+). Conclusion The cytologic features of EAS may resemble those of other neoplasms. In vealuating tumors with epithelioid morpholog, mesenchymal tumors should also be considered so that appropriate antibodies can be included in the panel for immunobistocbemistry. The importance of reviewing the patient's previous biopsy materials cannot be overemphasized.