Mediastinal germ cell tumors are uncommon (2 to 10% of germ cell tumors), and around 100 new cases are diagnosed annually. Their relationship with hematological disorders is an unique aspect of these tumors. The hematological disorder may be part of the natural history of the germ cell tumor, both sharing the same abnormal totipotential stem cell. The two most common hematological neoplasms seen in this syndrome are acute leukemia and malignant histiocytosis. The finding of the marker chromosome isochromosome i(12p) in the mediastinal germ cell tumors and associated malignant disorder is a suggestion that both tumors may arise from a common progenitor cell. A more remote possibility is that the hematological disorder is secondary to the chemotherapy used to treat the mediastinal germ cell tumors, mainly when etoposide is part of the treatment. In this instance, association with abnormalities of chromosome 11 is common. Habitually, both malignant diseases have an aggressive behaviour and carry a poor prognosis. New approaches are advisable in the staging and treatment of these patients.
mediastinal germ cell tumor; hematological disorders; isochromosome; etoposide related-leukemia