Evaluation and Staging of Ewing Sarcoma and Rhabdomyosarcoma

Ewing sarcoma family of tumors (ESFT) is a malignant small round blue cell tumor of bone. Approximately 80% of ESFT cases manifest in the first two decades of life, with 80% originating in the bones. ESFT most often manifests as a large, rapidly growing solitary mass and can occur virtually anywhere in the body involving bone or soft tissues, superficial or deep. Symptoms vary and depend on tumor location and extent, influenced by mass effect or invasion of adjacent structures. Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma in children and represents a high-grade neoplasm of embryonal mesenchyme which is destined to become skeletal muscles; that means they have a propensity for myogenic differentiation. Although a rare disease, RMS is a fairly common form of childhood cancer and is the most common soft tissue sarcoma in children. The chapter describes the presentation, evaluation, and staging of ESFT and RMS.