This chapter covers the rare tumors of childhood. No attempt has been made to consider the rarest of the rare tumors, and the focus is on the more common of the rare pediatric tumors that do not fall into other…
The histiocytoses constitute a collection of rare hematologic diseases that resist easy classification, at least in part because of the imprecise definition of “histiocyte.” “Histiocyte” broadly refers both to cells of the macrophage lineage and to dendritic cells (DCs), only…
Germ cell tumor (GCT) is the designation given to neoplasms arising from the cells of the germline—the cells that are destined to become either the egg or the sperm. A number of unique features of these tumors including their bimodal…
Osteosarcoma is the most common primary bone tumor. There are approximately 600 cases/year in the United States. The term osteosarcoma was first used in the early 1800s by Alexis Boyer, the imperial family surgeon for Napoleon. Although low-grade forms of…
In 1921 James Ewing described the cancer that came to carry his name: a primary bone tumor composed of small round blue cells and devoid of the malignant osteoid that characterizes osteosarcoma. Subsequently, pathologists described other clinicopathologic entities initially thought…
Soft tissue sarcomas of childhood and adolescence constitute a heterogeneous group of tumors that exhibit features of mesenchymal differentiation ( Tables 60-1 and 60-2 ). From a pediatric oncology perspective, the various types of rhabdomyosarcoma, the most common soft tissue…
Pathologic Classification of Rhabdomyosarcoma The term rhabdomyosarcoma (RMS) comprises a heterogeneous family of soft tissue cancers that are related in poorly understood ways to the skeletal muscle lineage. Some of these tumors occur in the vicinity of skeletal muscle, but…
Introduction and Epidemiology Liver tumors in children account for approximately 1.1% of all malignancies in children younger than 20 years of age according to the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) reports. The age-adjusted incidence rate of…
Tumors of the central nervous system (CNS) account for approximately 25% of pediatric cancer but are now the leading cause of cancer-related mortality in children. The complexities of tumors in this site are related to the large number of different…
Retinoblastoma is the most frequent neoplasm of the eye in childhood and the third most common intraocular malignancy in all ages, following malignant melanoma and metastatic carcinoma. Retinoblastoma represents 2.5% to 4% of all pediatric cancers but 11% of cancers…