Abstract
We report a case of embryonal carcinoma diagnosed by fine needle aspiration cytology of specimens from the left cervical lymph node by immunostaining using liquid-based cytology (LBC). A male patient in his 30s was introduced to our hospital, complaining of swelling of the left cervical region. Left cervical lymph node aspiration cytology revealed neoplastic cells possessing large, irregularly shaped nuclei with a high N/C ratio, and prominent nucleoli, both in the conglomerate and diffuse forms. Embryonal carcinoma was suspected on the basis of LBC of the specimens showing positivity for CD30, Oct3/4, SOX2, and cytokeratin AE1/AE3. CT showed lymph node enlargement from the left cervical region to the upper mediastinum, and from the para-aortic area to the area around the left common iliac artery, whereas FDG-PET examination demonstrated strong FDG accumulation in these enlarged lymph nodes. Weak FDG accumulation was noted in the left testis , but on palpitation and ultrasonographic and CT examinations, no tumor was detected in the testes. It is important to be aware of the possibility that lymph node aspiration cytology and other materials may lead to the diagnosis of embryonal carcinoma. LBC specimens and the appropriate markers in immunostaining are believed to be useful for diagnosis.
