Ewing Sarcoma

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This blog is for informational purposes only and should not be taken as medical advice. Content is sourced from third parties, and we do not guarantee accuracy or accept any liability for its use. Always consult a qualified healthcare professional for medical guidance.

What is Ewing Sarcoma?

Ewing sarcoma is a rare, aggressive bone/soft tissue cancer, part of the Ewing family of tumors, originating from primitive neuroectodermal cells with EWSR1 gene translocations. It affects bones (85%, pelvis, long bones) or soft tissues (15%), primarily in children/teens (peak 10-20 years), with ~250 US cases annually in 2025. It’s the second most common bone cancer in youth, often metastatic at diagnosis (25%).

Symptoms

Symptoms include localized pain (intermittent, worsening at night), swelling/lump at tumor site, limited motion, fever, fatigue, weight loss, and pathological fractures. Metastatic disease causes lung symptoms (cough, shortness of breath) or bone pain. Symptoms mimic infections or injuries, delaying diagnosis by 3-6 months.

Causes

The primary cause is t(11;22) translocation creating EWS-FLI1 fusion gene in 85%, disrupting cell regulation. Risk factors include Caucasian ethnicity, male gender (1.5:1), and age (adolescents). No strong environmental or hereditary links, though rare in African/Asian populations. In 2025, genomic studies explore fusion protein’s role in oncogenesis.

Diagnosis

Diagnosis uses X-ray (showing onion-skin periosteal reaction), MRI/CT for extent, PET/bone scan for metastasis, and biopsy with immunohistochemistry (CD99+) and FISH/PCR for EWSR1. Bone marrow biopsy checks involvement. In 2025, NGS identifies fusions in 95%.

Treatment

Multimodal: neoadjuvant chemotherapy (vincristine, doxorubicin, cyclophosphamide, ifosfamide, etoposide) shrinks tumor, followed by surgery (limb-salvage) and adjuvant chemo/radiation. SCT for high-risk. In 2025, targeted therapies (e.g., lurbinectedin) show promise in trials.

Future Outlook

In 2025, 5-year survival is 70-80% for localised, 30-40% for metastatic. Multi-agent chemo improves localised survival to 75%. Research on EWS-FLI1 inhibitors and immunotherapy could raise metastatic survival to 50% by 2030.

Sources

The information for Ewing sarcoma is sourced from Mayo Clinic’s “Ewing sarcoma – Symptoms and causes” for symptoms; WebMD’s “Ewing’s Sarcoma: Symptoms, Causes, Diagnosis, Treatment” for causes; NCBI’s “Ewing Sarcoma” for pathology; NCI’s “Ewing Sarcoma Treatment” for treatment; NORD’s “Ewing Sarcoma – Symptoms, Causes, Treatment” for overview; Cancer Therapy Advisor’s “Ewing Sarcoma – Diagnosis & Disease Information” for diagnosis; St. Jude’s “Ewing Sarcoma – Symptoms, Diagnosis and Treatment” for pediatric; OncoDaily’s “Ewing Sarcoma: Symptoms , Causes, Stages, Diagnosis and Treatment” for stages; Dana-Farber’s “Ewing Sarcoma” for symptoms.