A 48-year-old white male with no significant past medical history presented with complaints of progressive shortness of breath, cough productive of thick whitish sputum, drenching night sweats, diminished appetite and unquantified weight loss which progressed over a period 2 weeks. No history of haemoptysis, chest pain, fever or chills. He has a smoking history of 25 pack years and remote history of marijuana use. On examination patient was afebrile with a heart rate of 105 beats/min and respiratory rate of 25/min and saturation of 94% on 4 l of oxygen. Chest exam revealed diffuse coarse inspiratory crackles and gynaecomastia. Genital exam did not reveal any scrotal mass. The remainder of the physical examination was unremarkable. Laboratory data was significant for white blood cell 14 900/mm, haemoglobin 14 g/dl; comprehensive metabolic profile was within normal limits except for aspartate transaminase 77 U/l, alanine transaminase 62 U/l, alkaline phosphatase 253 U/l and albumin 1.9 mg/dl. Other significant laboratory data was β human chorionic gonadotrophin (HCG) 16 634 mIU/ml, lactic dehydrogenase 572 mg/dl, normal serum α-fetoprotein and negative HIV test. Chest x-ray was significant for bilateral pulmonary nodules (figure 1). Doppler ultrasound of the testes and mammography of breasts were negative for malignancy (figure 2). CT scan of the chest and abdomen revealed extensive lymphadenopathy in the mediastinum extending to the para tracheal area with extensive and multiple bilateral pulmonary nodules (figure 3) and multiple low density filling defects in the liver some with thick vascular walls. These findings were suspicious for a combination of cysts and metastasis of the liver (figure 4). There was no retroperitoneal tumour or lymphadenopathy and other visceral organs were also normal. MRI of the brain showed less than 1 cm probable metastatic lesion in the left thalamus and right subcortical matter (figure 5). However due to the small size and depth of lesions the neurosurgical consultants indicated that biopsy was not feasible. Due to the normal high resolution ultrasound scan of the testes and absence of retroperitoneal mass and extent of pulmonary involvement the urology and oncology consultants agreed not to proceed with exploration and orchiectomy. CT guided biopsy of right lung lesion showed the majority of the neoplasm to be necrotic and hemorrhagic, with the few viable islands demonstrating syncytiotrophoblastic and cytotrophoblastic-like cells, with immunohistochemical results consistent with choriocarcinoma (figure 6). Based on the above findings a diagnosis of primary pulmonary choriocarcinoma with probable metastasis to the liver and brain was made.

During the course of treatment pulmonary function test was monitored and remained unchanged from baseline. Patient showed marked clinical improvement. Serum β HCG dropped from 16 000 to 900. Patient continued to do well and after the fourth cycle of chemotherapy, serum β HCG dropped further to 11. However follow-up CT scan of the chest for restaging revealed significant bulk of tumour (figure 7). Postchemotherapy thoracoscopic wedge resection of the left lower lobe revealed persistence of malignant cells consistent with choriocarcinoma. Patient rapidly deteriorated after surgery with respiratory failure and died 5 days after.

Extragonadal germ cell tumours (EGCT) represent 2–5% of all germ cell tumours.¹ Primary chriocarcinoma is one of the non-seminomatous EGCT that occur mostly in young men. An international analysis of 635 cases of EGCT of the mediastinum and retroperitoneum has shown ages ranging from 14 to 79 with a median age of 30 years.² Primary choriocarcinoma is an exceedingly rare and aggressive tumour with much worse prognosis than other histologic subtypes owing to the haematogeneous dissemination at the time of diagnosis.