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SJPROTON2: Effects of Patient Positioning on Accuracy of Pediatric Proton Therapy

Estimating Setup Uncertainty in Pediatric Proton Therapy Using Volumetric Images



Diseases Treated:


Eligibility Overview:

This is a non-therapeutic clinical trial open only to St. Jude patients.

  • St. Jude patients receiving at least 5 daily fractions of proton therapy
  • All patients receiving proton therapy at St. Jude will be screened for participation.
  1. Brief Summary

    The sharp dose gradient from proton therapy with pencil beam scanning provides a great opportunity to deliver high radiation doses to tumors while sparing surrounding normal tissues. However, inaccurate patient positioning may lead to tumor under-dosing and increased risk of marginal recurrence.

    This research study establishes a repository for imaging data generated during image-guided proton therapy for various pediatric cancers. The data facilitate the estimation of patient positioning uncertainty, the comparison of image guidance methods, and the identification of factors contributing to large setup deviations to improve the accuracy of radiation therapy in the future.

    Primary Objective

    • To establish a repository of imaging data acquired during the radiation therapy course with linked radiation treatment plans and clinical information from pediatric patients of all cancer types receiving image-guided proton therapy to facilitate secondary and exploratory objectives

    Secondary Objectives

    • To estimate distributions of patient setup uncertainty measured with daily pre-treatment volumetric cone beam computed tomography (CBCT) scans
    • To compare patient setup corrections derived based on 2D (orthogonal radiographs) and 3D (volumetric CBCT scans) image guidance
    • To assess residual setup errors after CBCT-guided correction based on post-correction repeat CBCT
    • To estimate distributions and time trends of patient motion during a radiation therapy course based on weekly pre- and post-treatment CBCT scans
    • To identify clinical and treatment factors that contribute to significantly large setup uncertainty and intra-fractional movement in pediatric patients

    Exploratory Objectives

    • To determine variation in patient anatomy using images acquired during the treatment course.
    • To evaluate the usefulness of on-treatment CBCT scans for detecting daily changes in proton ranges, evaluating deviations from planned tumor dosimetry, and triggering adaptive replanning.

    Eligibility Criteria

    Inclusion criteria include:

    • St. Jude patients receiving at least 5 daily fractions of proton therapy

    Exclusion Criteria include:

    • Previous enrollment on this study
    • Pregnancy or breastfeeding

    Study Sites

    St. Jude Children’s Research Hospital, Memphis, Tennessee

  2. About this study

    Doctors use proton therapy to treat tumors with large amounts of radiation without hurting the surrounding tissue. This study will research how the patient’s position and setup affect the radiation procedure. The results may help to improve radiation therapy in the future.

    Purpose of this clinical trial

    The main goal of this study is to collect information about how a patient is positioned and set up for radiation therapy.

    Eligibility overview

    • St. Jude patients receiving at least 5 daily fractions of proton therapy
  3. SJPROTON2 Quick View
    Sponsors St. Jude Children's Research Hospital identifier NCT04125095
    Trial Start Date January 2020
    Estimated Enrollment 1,000
    Study Type Observational
    Conditions Pediatric cancer
    Ages All
    Principal Investigator Chia-ho Hua, PhD
    Study Sites St. Jude Children's Research Hospital
    For a consultation or to discuss SJPROTON2 St. Jude Physician/Patient Referral Office


Chia-ho Hua, PhD
St. Jude Children's Research Hospital
262 Danny Thomas Place
Memphis, TN  38105 USA
Voice: 1-888-226-4343 or 901-595-3384
24-Hour Emergency Access Pager: 1-800-349-433

The above information is intended to provide only a basic description about a research protocol that may be currently active at St. Jude. The details made available here may not be the most up-to-date information on protocols used by St. Jude. To receive full details about a protocol and its status and or use at St. Jude, a physician must contact St. Jude directly.