extragonadal germ cell tumors ( eggcts ) have the same histological components as their 
 gonadal counterparts , but a gonadal mass is not detectable by palpation or high - resolution 
 ultrasonography ) here , we report a case of primary mediastinal seminoma with complete obstruction of the 
 superior vena cava and no recurrence of the residual mass after intensive chemotherapy .
his bilateral jugular 
 veins were distended , and swollen lymph nodes were palpable in the right subclavicular 
 region .
a chest x - ray showed a mediastinal mass . computed tomography ( ct ) of the chest 
 revealed a solid soft tissue mass ( 95  75  112 mm ) [ in diameter ] in the upper mediastinum , 
 as well as a leftward displacement of the trachea and complete obstruction of the superior 
 vena cava ( figure 1figure 1pretreatment ct shows a solid soft tissue mass ( 95  75  112 mm ) in the upper 
 mediastinum , with leftward displacement of the trachea and complete obstruction of the 
 superior vena cava . ) .
based on the suspicion of a mediastinal tumor with lymph node metastasis , 
 mediastinal radiotherapy and methylprednisolone were immediately started .
biopsy of the 
 right subclavicular lymph nodes revealed metastatic seminoma ( figure 2 
 figure 2biopsy specimen from a right subclavicular lymph node .
well - defined tumor cells with 
 large nuclei and clear nucleoli and a large clear reticulum are formed as map - like 
 alveolar tumor cells .
cobblestone growth can be seen with lymph node involvement 
 surrounding the alveolar tissue . ) , and the patient was referred for chemotherapy .
pretreatment ct shows a solid soft tissue mass ( 95  75  112 mm ) in the upper 
 mediastinum , with leftward displacement of the trachea and complete obstruction of the 
 superior vena cava .
well - defined tumor cells with 
 large nuclei and clear nucleoli and a large clear reticulum are formed as map - like 
 alveolar tumor cells .
lactate dehydrogenase , -human chorionic gonadotropin and alpha - fetoprotein were all in the 
 normal ranges .
ultrasound revealed a uniform , echogenic structure of the bilateral 
 testicles , without any findings suggestive of malignancy .
radiotherapy and methylprednisolone were discontinued , and systemic chemotherapy was 
 simultaneously started with a combination of cisplatin , bleomycin and etoposide ( bep ) .
since 
 lung function test values deteriorated after one cycle of bep , bleomycin was excluded from 
 subsequent chemotherapy , and the regimen continued with etoposide plus cisplatin ( ep ) . a 
 partial response was observed after completing 3 cycles , but no further shrinkage was 
 observed on subsequent examinations .
salvage surgery was then considered for the residual mass because the superior vena cava 
 was still completely obstructed by the tumor .
although implantation of a prosthetic vessel 
 was required , the procedure was not performed because it was considered to be a high risk 
 surgery .
instead , the patient received 2 courses of vinblastine , ifosfamide and cisplatin 
 ( veip ) as salvage chemotherapy . on completion of the chemotherapy ,
the evaluable lesions 
 were considered to represent a " stable disease " ( figure 
 3figure 3posttreatment ct shows less enhancement of a smaller soft tissue mass ( 30  18  36 
 mm ) . ) . as of december 2010
, there is no evidence of residual tumor growth , new masses or 
 metastatic foci .
the patient is being closely followed up on an outpatient basis and has 
 been free of recurrence for 32 months after intensive treatment .
posttreatment ct shows less enhancement of a smaller soft tissue mass ( 30  18  36 
 mm ) .
our patient was first diagnosed as having an egct arising from the mediastinum when he 
 presented with chronic cough and complete obstruction of the superior vena cava . since few patients with early germ cell tumors arising in the mediastinum
have any 
 symptoms , these tumors are often quite large by the time they are diagnosed and the mean 
 maximum diameter of such tumors is reportedly 4.6 cm ) in 2008 , kesler et al .
reported that 10 surgical deaths occurred among 158 
 patients who underwent additional resection of residual primary mediastinal nonseminomatous 
 tumors ) like primary testicular seminoma , primary mediastinal seminoma has a good prognosis , and 
 the rate of necrosis of the residual mass is as high as 92% when partial remission is 
 obtained after chemotherapy )
 a 20-year - old man was admitted to our hospital with persistent cough and dyspnea . 
 he had 
 bilateral distention of the jugular veins , and swollen lymph nodes were palpable in the 
 right subclavicular region . 
 plain x - ray and computed tomography ( ct ) of the chest showed a 
 solid soft tissue mass in the upper mediastinum , with leftward displacement of the trachea 
 and complete obstruction of the superior vena cava . 
 mediastinal radiotherapy ( 1.8 gy / day ) 
 and methylprednisolone ( 100 mg / day ) were started immediately . 
 biopsy of the right 
 subclavicular lymph nodes revealed metastatic seminoma . 
 the patient was referred for 
 chemotherapy , which was performed with a combination of cisplatin , bleomycin and etoposide 
 ( bep ) . 
 a partial response was observed after completion of 3 cycles of chemotherapy , but 
 there was no further tumor shrinkage after additional salvage chemotherapy . 
 the patient is 
 being followed up on an outpatient basis and has been free of recurrence for 32 months 
 after intensive treatment . 