How does Ewing's sarcoma differ from osteosarcoma?
Both tumors occur in adolescents, but their nature is different. Osteosarcoma comes from bone-forming cells and produces abnormal bone itself, while Ewing's sarcoma consists of small, round cells and does not produce bone. The typical location also differs: osteosarcoma most often occurs near the knee, and Ewing's sarcoma occurs in the pelvis, ribs, scapula, spine and in the middle part of long bones. Ewing's sarcoma is sensitive to both chemotherapy and radiation therapy, which expands the choice of treatment options for difficult-to-reach locations.
- Different origins of tumor cells
- Ewing's sarcoma does not form bone tissue
- Typical locations: pelvis, ribs, spine
- Characteristic genetic rearrangement
- Sensitivity to radiation therapy
- Can also grow in soft tissues
Symptoms
The leading symptom is pain in the affected bone, at first intermittent, then more and more persistent, worsening at night and not associated with load. A swelling appears above the lesion, sometimes with redness and a local increase in temperature, which resembles inflammation. General manifestations are often observed: low-grade fever, weakness, decreased appetite, weight loss, increased ESR and leukocytosis. If located in the spine or pelvic bones, back pain, weakness in the legs, impaired sensitivity and function of the pelvic organs are possible.
- Increasing bone pain, especially at night
- Swelling and redness over the lesion
- Fever and weakness
- Loss of appetite and weight
- Lameness and limitation of movement
- Neurological disorders due to spinal lesions
- Increased ESR in blood test
Diagnostics
The first step is an x-ray of the affected bone, where destruction of bone tissue and characteristic multilayer detachment of the periosteum are visible. MRI accurately shows the extent of the tumor and the soft tissue component, which is often significant in this sarcoma. An assessment of the prevalence is required: CT scan of the chest, examination of the entire skeleton and bone marrow, since Ewing's sarcoma often produces lesions in the lungs, bones and bone marrow. The diagnosis is confirmed by a biopsy with mandatory molecular genetic testing, which reveals characteristic gene rearrangements.
- X-ray of the affected bone
- MRI with evaluation of the soft tissue component
- CT chest
- Whole skeleton examination
- Bone marrow puncture and biopsy
- Tumor biopsy with molecular testing
- LDH and complete blood count
Treatment
Ewing's sarcoma is always considered a disease that requires systemic treatment, even if there is only one focus: microscopic tumor cells may be present in other organs. Therefore, treatment begins with several courses of chemotherapy, which reduces the tumor and affects hidden lesions. Then local treatment is carried out: surgery to remove the tumor, radiation therapy, or a combination of both - the choice depends on the location and the ability to remove the lesion. After the local stage, chemotherapy is continued. All treatment is carried out according to the protocol in a specialized center.
- Chemotherapy as a mandatory basis of treatment
- Surgical removal of the tumor
- Radiation therapy for difficult-to-reach locations
- Combination of surgery and radiation according to indications
- Continuation of chemotherapy after local treatment
- Rehabilitation and restoration of limb function
- Long-term follow-up after completion of treatment
Why is it important not to wait
The interval between the first complaints and diagnosis of this tumor often exceeds several months, and the main reason is the similarity with trauma and inflammation. The child is prescribed rest, physiotherapy and painkillers, which temporarily reduce pain and create the illusion of improvement. Meanwhile, it is the extent of the tumor at the time of treatment that most strongly influences the outcome. Therefore, for bone pain that lasts longer than two to three weeks, an x-ray is needed, and for suspicious changes, a referral to a pediatric oncologist without intermediate courses of treatment.
- Symptoms can easily be mistaken for injury or osteomyelitis
- Painkillers mask the problem
- Physiotherapy for unclear bone pain is not indicated
- X-ray for pain longer than two to three weeks
- Early treatment improves outcome
- Referral to a pediatric oncologist without delay
