Definition
A primary mediastinal germ cell tumour composed of epithelial-looking cells.
This is a tumour of young males. A few patients have Klinefelter's syndrome.
There is often invasion of adjacent structures.
The tumour cells form sheets, tubules or papillae. The cells are large and polygonal or columnar with large vesicular nuclei having one or more prominent nucleoli. The cytoplasm is variably basophilic, eosinophilic or clear. There is a high mitotic rate, with atypical mitoses. Necrosis is particularly common in combined yolk sac tumours.
It may occur as a pure form or a mixed germ cell tumour in combination with teratoma, choriocarcinoma or seminoma. In the second decade, it may occur in association with yolk sac tumour. In total, pure and mixed embryonal carcinoma accounts for 12% of mediastinal germ cell tumours.
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CD30 |
85-100%0 |
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Low MW cytokeratins |
positive0 |
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30%0 |
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negative0 |
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33%0 |
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|
negative0 |
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negative0 |
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30%0 |
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Choriocarcinoma if the tumour is extensively syncytial, but embryonal carcinoma lacks a cytotrophoblastic component.
Most prepubertal germ cell tumours are yolk sac tumours.
Large cell carcinoma of the lung.
Metastasis from a gonadal primary.
About 25% of cases show pulmonary metastases at presentation. Other sites of metastasis are liver, brain and bone. There is about 50% long term survival in adults, 80% in children, after chemotherapy.
0 Tumours of the Lung, Pleura, Thymus and Heart. WHO Classification of Tumours. IARC Press 2004.
This page last revised 19.1.2006.
©SMUHT/PW Bishop