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Tests tumor-adapted radiation doses in people with Ewing sarcoma

Tests radiation doses adjusted to tumor features in people with Ewing sarcoma.

Plain-language title generated from the registry record
Registry title: Biologically-Adapted, Dose-Escalated Radiotherapy for the Treatment of Ewing Sarcoma, BEAR Trial

Key facts

Where
Phoenix and Rochester, United StatesSee the 2 sites

Where in United States

  • Mayo Clinic in ArizonaPhoenix, United StatesTaking people
  • Mayo Clinic in RochesterRochester, United StatesTaking people

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Trial details

Who runs it
Mayo Clinic
Trial code
NCT07188532
Record updated
6 October 2026
Original description
This clinical trial evaluates the effect of radiotherapy doses based on tumor size and tumor-specific characteristics (biologically-adapted) in treating patients with Ewing sarcoma. Radiotherapy uses high energy x-rays, particles, or radioactive seeds to kill tumor cells and shrink tumors. Conventional radiotherapy uses minimal imaging support to determine the positioning of radiotherapy. Hypofractionated radiotherapy delivers higher doses of radiotherapy over a shorter period of time and may kill more tumor cells and have fewer side effects. Dose-escalated radiotherapy uses doses that are higher than those used in conventional radiotherapy. Larger tumor sizes and other tumor-specific characteristics have been shown to be related to poorer outcomes. In addition, after dose-escalated radiotherapy, patients with larger tumors have demonstrated improved control of the disease at the primary tumor site. Giving biologically-adapted, dose-escalated radiotherapy may reduce the return of the cancer at the primary tumor site in patients with Ewing sarcoma with large tumors and other unfavorable characteristics. This clinical trial also evaluates the role of biomarkers in patients with Ewing sarcoma. Studying samples of blood and tumor tissue from patients with Ewing sarcoma in the laboratory may help doctors learn more about predicting the amount of disease and the likelihood of the cancer coming back.Read full original descriptionShow less

Biologically-Adapted, Dose-Escalated Accelerated Radiotherapy for Ewing Sarcoma (BEAR)

This clinical trial evaluates the effect of radiotherapy doses based on tumor size and tumor-specific characteristics (biologically-adapted) in treating patients with Ewing sarcoma. Radiotherapy uses high energy x-rays, particles, or radioactive seeds to kill tumor cells and shrink tumors. Conventional radiotherapy uses minimal imaging support to determine the positioning of radiotherapy. Hypofractionated radiotherapy delivers higher doses of radiotherapy over a shorter period of time and may kill more tumor cells and have fewer side effects. Dose-escalated radiotherapy uses doses that are higher than those used in conventional radiotherapy. Larger tumor sizes and other tumor-specific characteristics have been shown to be related to poorer outcomes. In addition, after dose-escalated radiotherapy, patients with larger tumors have demonstrated improved control of the disease at the primary tumor site. Giving biologically-adapted, dose-escalated radiotherapy may reduce the return of the cancer at the primary tumor site in patients with Ewing sarcoma with large tumors and other unfavorable characteristics. This clinical trial also evaluates the role of biomarkers in patients with Ewing sarcoma. Studying samples of blood and tumor tissue from patients with Ewing sarcoma in the laboratory may help doctors learn more about predicting the amount of disease and the likelihood of the cancer coming back.

Inclusion: Histological confirmation of Ewing sarcoma, including both skeletal and extra-skeletal primary tumors. Patients with "Ewing-like" sarcoma may be eligible if patients are planned to be treated per Ewing treatment paradigms, as defined in this clinical trial; Patients of age ≥ 2 years are eligible for the study; Lansky or Karnofsky performance status ≥ 70; Ability to provide written informed consent and complete questionnaire(s) by themselves or with assistance; Willing to provide blood samples for correlative research purposes; Willing to provide biopsy sample to run Mayo Complete Solid Tumor Panel if tumor size is >= 8 cm.

Exclusion: Prior chemotherapy or radiotherapy that, in the opinion of the treating medical oncologist or radiation oncologist, is considered to interfere with the current treatment or measurement of outcomes; Receiving any investigational agent which would be considered as a treatment for the primary neoplasm that is considered by the investigator to interfere with the current treatment or measurement of outcomes; Note: Co-enrollment on another clinical trial is allowed per the treating radiation oncologist's discretion; Other active malignancy ≤ 1 year prior to registration that is considered by the investigator to interfere with the current treatment or measurement of outcomes; Patients that have severe co-morbid systemic illness or other disease which would interfere significantly with the current treatment or measurement of outcomes; Patients that have active uncontrolled systemic infection, symptomatic congestive heart failure, unstable angina, cardiac arrhythmia, or psychiatric illness or social situation that would limit study adherence; Any of the following:; Pregnant patients; Nursing patients.

ClinicalTrials.gov NCT07188532