Mediastinal Germ Cell Tumors

Primary mediastinal germ cell tumors represent a unique group of tumors that share similar histopathological features with their counterparts in the gonads. The histogenesis of mediastinal germ cell tumors is not completely understood. Because the histology and in some cases the clinical features of these tumors may also be similar to those in the gonads, it is highly important to properly evaluate the imaging in those patients. Nevertheless, these tumors represent a diagnostic challenge and often a mediastinal biopsy may be the one used to start medical treatment in these patients. Therefore, it is highly important to become familiar not only with the different histopathological growth patterns of these tumors but also with their immunohistochemical characteristics. In general, mediastinal germ cell tumors follow similar immunophenotypes as those in the gonads. However, it is important to highlight that clinically, the majority of patients with mediastinal germ cell tumors are young men and these tumors appear to affect this particular population.