Testicular cancer with enlarged mediastinal lymph nodes: a diagnostic pitfall.

A patient with embryonal cell carcinoma restricted to the left testicle, without retroperitoneal but with mediastinal lymph node enlargement and highly elevated serum alpha-fetoprotein levels, is presented (T1N4M0). Because stage III of the disease was presumed, he received chemotherapy, which was unfortunately complicated by a bleomycin-induced pneumonitis. At re-evaluation after chemotherapeutic treatment, it appeared that the tumor marker level had decreased exponentially after the operation and that the mediastinal lymph node enlargement was due not to metastatic disease but to sarcoidosis. The necessity of calculating the half-life of tumor markers after operation and histological examination of the mediastinal lymph nodes prior to chemotherapy in such cases, is discussed.