Primary mediastinal tumors are relatively rare. The relative incidence of these tumors indicates that neurogenic tumors are the most common tumor seen constituting 21 % of all cases, thymomas 19%, lymphomas 12.5%, germ cell tumors 10%, primary carcinomas 4.6%, mesenchymal tumors 6%, endocrine tumors 6%, cysts 18%. In adults, the majority of thyroid tumors, thymomas, mediastinal germ cell tumors and teratomas are located in the superior and anterior mediastinum. Of the neurogenic tumors 18% are located in the posterior mediastinum, and 50% of mediastinal lymphomas are in the middle mediastinum. In adults, the incidence of anterosuperior, middle and posterior mediastinal tumors is about 54%, 20% and 26% respectively. However, in children the posterior mediastinum contains 63% of the lesions, the anterior mediastinum contains 26% and the middle mediastinum II %. The majority of the tumors are benign in character with a ratio of benign to malig nant of about 60 to 40. The relative incidence of malignant mediastinal tumors in children is about 50%. Even though mediastinal tumors are not common, they represent a unique problem with regards to treatment whether by surgery, radiation therapy and/or systemically administered chemotherapy. The volume by WOOD and THOMAS deals with each of these issues in detail and presents a logical and important approach to the management of mediastinal tumors.
