Pediatric rhabdomyosarcoma

Pediatric rhabdomyosarcoma (RMS) composes just under one half of all pediatric soft tissue sarcomas in the United States (US) (Li et al. 2008). It is a highly malignant neoplasm, originating from mesenchymal cells destined for striated muscle differentiation. It can arise anywhere in the body, including the head and neck (35%), genitourinary tract (24%), extremities (19%), and elsewhere (22%) (Pappo 1995). Pediatric RMS treatment represents a diverse and challenging paradigm, due to the differing prognoses based on site of origin and histology. Chemotherapy comprises the backbone of curative treatment, as RMS tends to disseminate early in its course, with surgery and/or radiotherapy used for local control of the primary site. Since the creation of the Intergroup Rhabdomyosarcoma Study Group (IRSG) in the early 1970s, rates of cure have steadily increased from 15 to 20% in the earliest studies to currently better than 80% for all non-metastatic patients (Crist et al. 1990, 2001; Maurer et al. 1993; Arndt et al. 2009; Raney et al. 2011).