Retroperitoneal tumors constitute a common and important problem in infants and children. Although they differ pathologically, their clinical features are so similar that they may be studied as one basic group. This review is concerned only with the neoplasms of surgical importance arising in the kidneys and in the autonomic nervous system and adrenal medulla. The teratomas and the retroperitoneal malignancies of other origin are statistically much less important and will be separately reported.
All of the lesions discussed herein arose in the retroperitoneal space, roughly extending from the 12th rib and diaphragm to the brim of the pelvis. We have not included tumors of lymphatic, mesenteric, pancreatic, intestinal, or ureteral origin. Neoplasms in infancy and childhood are usually derived from embryonic tissues, not from epithelial structures.
Incidence
Retroperitoneal tumors make up a major portion of the malignant neoplasms of the very young. After the fifth year, their relative proportion,