Metastatic embryonal carcinoma mimicking locally advanced non-small cell lung cancer

A 50-year-old man with a history of smoking of 45 pack-years underwent right lower lobectomy after neoadjuvant chemoradiotherapy for locally advanced non-small cell lung cancer diagnosed on a bronchial biopsy and standard imaging examinations, including chest-abdominal contrast-enhanced computed tomography (CT) and whole-body F-18 fluorodeoxyglucose positron emission tomography/CT. Left orchiectomy was performed simultaneously to treat the slightly swollen left testis, which had remained unchanged for over five years. The thoracic tumor was proven to be in pathological complete remission and the testicular lesion was pathologically diagnosed as an embryonal carcinoma. Furthermore, a pathological reevaluation of the preoperative bronchial biopsy specimen revealed the lung tumor to be a metastatic embryonal carcinoma.