Recurrent Ewing’s Sarcoma

When Ewing’s sarcoma returns after treatment or does not respond to initial therapy, patients face a challenging situation with limited standard treatment options. Understanding what recurrence means and what approaches are available can help patients and families navigate this difficult journey.

Table of contents

• What Is Recurrent Ewing’s Sarcoma?
• Prognosis and Factors That Matter
• Treatment Challenges and Approaches
• The Importance of Clinical Trials

What Is Recurrent Ewing’s Sarcoma?

Recurrent Ewing’s sarcoma is cancer that has returned after an initial response to treatment or that has not responded to treatment at all. This situation is also sometimes called relapsed or refractory disease.^[1] The cancer can come back in the same place where it first appeared (local recurrence), in nearby areas, or in distant parts of the body such as the lungs, which is the most common site for the disease to return.^[2]

Ewing’s sarcoma is a type of cancer that forms in bone or soft tissue and most commonly affects adolescents and young adults. While many patients with newly diagnosed Ewing’s sarcoma can become long-term survivors with initial treatment, relapse remains an important clinical problem.^[3]

Prognosis and Factors That Matter

The outlook for patients with recurrent Ewing’s sarcoma remains challenging. Research shows that the prognosis is generally poor, with the likelihood of cure remaining low.^[4] One study from England reported that among 64 patients who relapsed after initial therapy, average survival from the time of relapse was only 14 months.^[5]

Several factors have been identified that can help predict outcomes and guide treatment decisions. The time between the original diagnosis and when the cancer returns is particularly important. A longer interval between the primary diagnosis and the appearance of recurrent disease is associated with a better prognosis.^[6] Patients who relapse more than two years after diagnosis tend to have better outcomes than those who relapse earlier.^[7]

The location of the recurrence also matters. Research from St. Jude Children’s Hospital found that among 71 patients with recurrent Ewing’s sarcoma, those with local recurrence had a five-year relapse-free survival of 22 percent compared to 18 percent for those with distant recurrence. Patients with both local and distant recurrences had the poorest outcomes, with a five-year relapse-free survival of only 8 percent.^[8]

Patients who relapse while still receiving initial therapy generally do worse than patients who relapse after completing treatment.^[9]

Treatment Challenges and Approaches

There is currently no standard approach for treating recurrent Ewing’s sarcoma.^[10] This means that treatment decisions must be individualized based on each patient’s specific situation, including where the cancer has returned, how long it has been since the initial diagnosis, and what treatments were used before.

Treatment for recurrent disease typically involves multiple approaches. Options may include chemotherapy (medicines that kill cancer cells), surgery to remove tumors, radiation therapy (using high-energy rays to destroy cancer cells), or combinations of these methods.^[11] This approach using two or more treatment methods together is called multi-modality treatment.^[12]

A variety of chemotherapy regimens have produced responses in patients with recurrent Ewing’s sarcoma, but no studies have been completed to show that any one particular approach is better than another.^[13] Research has shown that the highest objective response rates have come from chemotherapy combinations that include a drug called irinotecan.^[14]

Surgery can play an important role in certain situations. Studies suggest that patients with local recurrences who undergo radical surgery have better survival than those who do not have surgery.^[15] For patients with cancer that has spread only to the lungs, radiation therapy may provide benefit.^[16]

Many questions remain unanswered about the best way to treat recurrent Ewing’s sarcoma. The optimal length of therapy for salvage regimens (treatments given after initial therapy has failed) and the best use of local control measures such as surgery and radiation are still unknown.^[17]

The Importance of Clinical Trials

Because the likelihood of cure remains low and the gaps in medical knowledge are significant, enrollment in clinical trials (research studies testing new treatments) should be strongly encouraged for patients with recurrent Ewing’s sarcoma when possible.^[18] Clinical trials may offer access to new therapies that are not yet widely available and contribute to advancing medical knowledge that could help future patients.

Patients with rare tumors such as Ewing’s sarcoma benefit from multidisciplinary collaboration, which brings together different types of doctors and specialists. This team approach can result in improved quality of care and better treatment outcomes.^[19] Because Ewing’s sarcoma is relatively rare, some pediatric and adult cancer doctors may be less familiar with managing patients who have relapsed disease.^[20]

The multi-modality approach to treatment for Ewing’s sarcoma requires that patients be treated by a team that may include the primary care physician, a surgeon experienced in bone tumors, specialists who study tissue samples, radiation oncologists, pediatric oncologists, rehabilitation specialists, nurses, social workers, and others. An experienced team is best found in specialty cancer centers that treat many patients with Ewing’s sarcoma.^[21]