종격동에 발생한 원발성 난황난 종양의 세침흡인 세포학적소견

초록

Primary Yolk sac tumor is a rare but highly malignant tumor, which accounts for the most frequent extragonadal nonseminomatous germ cell tumor in the mediastinum. The majority of patients are males in their twenties and thirties. Beacuse those features are usually not discernable as such in cytologic smears and aspirates might show papillary clusters of malignant epithelial cells arranged in papillary clusters in the mucoid background with necroinflammatory debris suggesting adenocarcinoma or embryonal yolk sac tumor in mediastinum. The patient was 40-year-old man with shief compalaint of vague chest pain and discomfort for a month accompanied by recently aggravated dyspnea. Computerized tomography revealed a huge mass in the left anterior mediastinum with severe right pleural effusion and multiple nodules in the cisceral pleura. Radiologically, the mass was 12x9cm in size with internal necrosis and calcifications along with a metastatic lesion in the right lung and muilitple lymphadenopathy involving the mediastinal and paratracheal lymph nodes. Fine needle aspiration smears contained mild to moderately cellular aspirates showing papillary clusters of loose aggregates of neoplastic cells with ill-defined cell norders. The tumor cells had pleomorphic and hyperchromatic nuclei with coarsely granular or vesicular chromatin. The nucleioli were prominent and mitosis was not infrequent. Hyaline droplets were not conspicuous. The background showed tumor diathesis. Incisional biopsy from the left supraclavicular lymph node demonstrated various histologic patterns of yolk sac tumor, including solid, reticular-microcystic and psueudopapillary. There were intracellular and extracellular hyaline globules which were PAS positive and distase resistant.