An interventional study of Proton Therapy (Adaptive) in Pediatric Solid Tumors, Rhabdomyosarcoma and Ewing Sarcoma, sponsored by St. Jude Children's Research Hospital. Recruiting at 1 site in United States. Per ClinicalTrials.gov, last updated 2026-08-21.
Sponsored by St. Jude Children's Research Hospital · Not applicable, Interventional, and Other
Pediatric patients receiving proton therapy for solid tumors or Hodgkin's lymphoma may experience anatomical changes during treatment that can affect proton therapy accuracy. This prospective single-arm study uses regular low-dose imaging to monitor these changes and adjust treatment plans as needed. Participants will receive weekly or every-other-week CT scans, with MRI when appropriate, to assess whether the original plan remains accurate. Treatment plans will be updated if tumor coverage decreases by more than 5% or if radiation dose to normal tissues increases by more than 10%; otherwise, the original plan will continue. The study aims to determine how often plan adjustments are needed and to identify which disease sites are most likely to experience significant anatomical changes during treatment.
Primary Objective:
Secondary Objectives
Proton therapy is a type of radiation treatment that can target tumors very precisely while protecting healthy organs. This is especially important for children. However, during the several weeks of treatment, a child's body and tumor can change. These changes may cause the radiation dose to miss part of the tumor or give too much dose to nearby organs.
In usual care, proton therapy plans are based on one CT scan taken before treatment starts. New scans are only done if the care team thinks a change has occurred. There is no standard process to regularly check whether the treatment plan is still accurate during therapy.
This study tests a structured approach to monitoring and adjusting proton therapy plans during treatment in children with solid tumors or Hodgkin's lymphoma.
About 100 pediatric patients receiving proton therapy at St. Jude Children's Research Hospital will take part. All patients will receive their prescribed proton therapy as usual. The study does not change the radiation dose or schedule.
Participants will receive additional CT scans, and MRI when needed, during treatment. Imaging will be done weekly or every other week to check whether the original treatment plan still provides good tumor coverage and protects healthy organs.
The treatment plan will be updated if:
If these changes are not seen, the original plan will continue. The extra imaging uses a low radiation dose.
The goal of this study is to learn how often proton therapy plans need to be adjusted to keep treatment accurate and safe. Results may help improve proton therapy care for children in the future.
238 studies on the registry are indexed under Rhabdomyosarcoma; 49 are open to participants now.
This study's planned enrollment of 100 is above the median of 42 across 202 interventional studies indexed under Rhabdomyosarcoma.
Browse Rhabdomyosarcoma studies →St. Jude Children's Research Hospital is the lead sponsor of 440 studies on the registry; 102 are open to participants now.
Of its 61 completed or terminated interventional studies of FDA-regulated products, 37 (61%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
All participants receiving proton therapy at St. Jude Children's Research Hospital will be screened for participation on this research protocol based on the Inclusion Criteria and the Exclusion Criteria. Qualified candidates will be selected during the consultation.
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
All enrolled participants receive standard of care proton therapy combined with systematic on therapy imaging (CT and/or MRI) during treatment. Imaging is used to generate verification plans to assess dose delivery relative to the original plan. Adaptive replanning is implemented if predefined dosimetric thresholds are exceeded.
Radiation: Proton Therapy (Adaptive)
Proton beam radiation therapy delivered per standard disease or site specific protocols, with additional on therapy CT and/or MRI imaging performed weekly or bi weekly during treatment. Verification planning is conducted using updated imaging, and treatment plans are adaptively replanned when tumor coverage decreases by ≥5% or organ at risk dose increases by ≥10% compared with the originally approved plan. Total dose, fractionation, and treatment schedule follow standard of care and are determined by the treating physician.
Rate of Replanning Treatment
Descriptive statistics for number of cases replanned during treatment course will be reported
Time frame: Captured during on-therapy imaging (occurring either weekly or bi-weekly) for the duration of the patient's treatment course (varies depending on individual cases, anywhere from roughly 6 weeks to 10 weeks)
Tumor Control Probability (TCP) and Normal Tissue Complication Probability (NTCP)
Descriptive statistics for V95% (tumor coverage) and OAR (organs-at-risk) will be reported, as well as signed-rank tests to evaluate adaptive planning effectiveness
Time frame: Captured during on-therapy imaging (occurring either weekly or bi-weekly) for the duration of the patient's treatment course (varies depending on individual cases, anywhere from roughly 6 weeks to 10 weeks)
Correlation between tissue discrepancies and changes in proton range, and deviations from intended plan quality
Spearman correlation will be reported, assessing the associations between factors
Time frame: Captured during on-therapy imaging (occurring either weekly or bi-weekly) for the duration of the patient's treatment course (varies depending on individual cases, anywhere from roughly 6 weeks to 10 weeks)
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