Clinical Background
The Ewing family of sarcomas are mesenchymal neoplasms that most frequently arise from soft tissue and bone, and are members of the group of small round cell malignancies.
Epidemiology
- Prevalence - approximately 225 new cases per year in U.S.
- Age
- Peak incidence in second decade
- 20% diagnosed in patients >20 years and patients <10 years
- Sex - slightly more common in adolescent males
- Ethnicity - unusual tumor in Asians and Africans
Risk Factors
- Chromosomal translocations
- Approximately 85% of cases demonstrate a translocation between chromosomes 11 and 22 [t(11;22)(q24;q12)]
- Remaining 15% may have translocations between chromosomes 22 and either chromosome 2, 7, 17, or 21
- Translocations between chromosomes 16 and 21 have also been rarely described
Pathophysiology
- Classic Ewing sarcoma is a monotonous population of small round cells with a high nuclear to cytoplasmic ratio
Clinical Presentation
- Symptoms and signs are based on location of tumor
- Tumor typically involves long bones and trunk
- Pain can be intermittent and variable
- Tumor can also be found in soft tissues
- Palpable mass at affected site
- May present at any site
- Metastatic disease
- Presence of metastatic disease is an unfavorable feature
See Also
