Ewing Sarcoma
Information about the causes, symptoms, diagnostic methods, and treatments for this type of cancer.
Symptoms and Causes
The term "sarcoma" refers to cancers that originate in the bones or soft tissues of the body, which can include muscles, cartilage, fibers, blood vessels, or connective tissues. In 1921, James Ewing first described a variety that originates in the bones and periosteum (the membrane covering and giving sensitivity to bones), which came to bear his name. This is a particularly aggressive type of cancer that commonly affects children and adolescents, though it can occur at any age.
In most cases, Ewing sarcoma originates in the femur, tibia, humerus, pelvis, spine, or chest. Depending on its etiology, several types are recognized:
- Bone Ewing sarcoma: originates in a bone.
- Extraosseous or extraskeletal Ewing sarcoma: originates outside the bone, in areas close to but not within the bone.
- Primitive neuroectodermal Ewing sarcoma: damages small, round, blue cells and is of primitive nature, meaning it forms during embryonic development.
- Askin tumor: occurs in the soft tissues of the chest wall. It originates from the neural crest, which is an embryonic structure located between the neural tube and the epidermis.
Scientific advances in recent years have significantly increased the life expectancy of individuals with this type of cancer. According to data from the Spanish Association Against Cancer, the survival rate is 68% five years after diagnosis and 63% after 10 years.
Symptoms
The most characteristic symptoms of Ewing sarcoma include:
- Palpable lumps in the chest, arm, leg, or pelvis.
- Pain
- Bone fractures
- Fatigue
- Fever
Causes
The causes of Ewing sarcoma are unknown, though it is linked to changes in the DNA of cells. Ewing sarcoma typically presents a translocation of the EWS gene from chromosome 22 with the FLI1 gene from chromosome 11.
Risk Factors
Ewing sarcoma can develop at any age. However, it is more common between the ages of 5 and 15.
Complications
Throughout the treatment of Ewing sarcoma, complications may arise, whether from surgery (which can sometimes be quite mutilating) or from chemotherapy or radiotherapy treatments.
Ewing sarcomas often metastasize, especially to the lungs.
Prevention
Sarcomas are rare tumors, for which there are no screening tests or preventive habits.
Which doctor treats Ewing sarcoma?
The management of Ewing sarcoma requires a multidisciplinary approach, involving many specialists such as radiologists, orthopedic surgeons, radiation oncologists, and nuclear medicine specialists, typically led by the medical oncologist, who plans the treatment globally and in a consensus manner.
Diagnosis
The most commonly used tests to diagnose Ewing sarcoma include:
- X-rays: simple images of the bone that allow initial identification of lesions.
- CT and MRI: provide better assessment of the lesion, especially its extent, whether there is an associated fracture, and the damage to surrounding tissues.
- Bone scintigraphy: involves the administration of a radioactive tracer that binds to the lesion with high affinity, allowing detection of the primary lesion and any metastases in other bones.
- Bone tissue biopsy
Treatment
The treatment of Ewing sarcoma is highly complex and should be approached in a center with experience. Generally, it requires a combination of several procedures or treatments:
- Chemotherapy: involves the administration of a combination of drugs intravenously. It is often given before surgery to reduce the tumor.
- Radiotherapy: uses electron radiation as a complement to chemotherapy or surgery.
- Surgery: the fundamental approach for Ewing sarcoma, and should always be performed by a specialized orthopedic surgeon.
