An interventional study of Proton GRID Radiotherapy in Unresectable Solid Tumor and Metastatic Cancer, sponsored by Washington University School of Medicine. Active, not recruiting at 1 site in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-07-13.
Sponsored by Washington University School of Medicine · Not applicable, Interventional, and Treatment
Spatially fractionated radiotherapy (SFRT or GRID) addresses some limitations of traditional stereotactic body radiation therapy by relying on beam collimation to create high-dose "peaks" and intervening low-dose "valleys" throughout the target volume. Standard palliative radiotherapy regimens provide limited durability of response, and there are challenges with delivery to large tumors or in previously irradiated fields. In this study, Proton GRID radiotherapy will be used to deliver three-fraction palliative radiotherapy to patients with tumors needing palliative radiation. The safety and efficacy of this approach will be assessed. It is hypothesized that GRID is highly effective, immunogenic, and associated with low rates of toxicity.
3,517 studies on the registry are indexed under Neoplasm Metastasis; 885 are open to participants now.
This study's enrollment of 24 is below the median of 54 across 2,767 interventional studies indexed under Neoplasm Metastasis.
Browse Neoplasm Metastasis studies →Washington University School of Medicine is the lead sponsor of 1,765 studies on the registry; 271 are open to participants now.
Of its 324 completed or terminated interventional studies of FDA-regulated products, 212 (65%) have results posted.
Counted across the registry records on this site, refreshed daily.
Planning to undergo palliative radiotherapy to unresectable or metastatic target lesion ≥ 4.5 cm in any dimension as measured with radiographic imaging or with calipers by clinical exam.
Exclusion Criteria:
Radiotherapy will consist of 20 Gy proton GRID radiotherapy x 3 fractions.
Radiation: Proton GRID Radiotherapy
Radiotherapy will consist of 20 Gy proton GRID radiotherapy x 3 fractions.
Radiation: Proton GRID Radiotherapy
The proton GRID radiotherapy prescription dose is 20 Gy x 3 fractions to the tumor, with an integrated dose of 6 Gy x 3 fractions to the PTV. Treatment to multiple lesions within the PTV is allowed (ex. a dominant lesion plus satellites). Multiple proton GRID radiotherapy plans may be delivered on the same day or different days, but they cannot overlap.
Rate of treatment-related acute toxicity
-Grade per CTCAE v5.0.
Time frame: From start of treatment through 90 days
Rate of treatment-related late toxicity
-Grade per CTCAE v5.0.
Time frame: From day 91 through 12 months
Change in PRO-CTCAE (General Inventory and Disease Specific Inventory Assessment)
PRO-CTCAE is a standardized inventory to collected patient reported symptomatic adverse events in clinical trials.
Time frame: Baseline, at last day of radiotherapy (day 3), within 2 weeks after completion of radiotherapy (day 14), 30 days, 90 days, 180 days, and 360 days
Change in PROMIS Global Health
PROMIS Global Health is a 10-item patient-reported questionnaire that assesses health related quality of life compared with normal values for the general population with the response options presented as a 5-point (as well as a single 11-point) rating scale. The question that uses an 11-point scale uses a response scale of 0-10 that is recoded to 5 categories (0 = 1; 1-3 = 2; 4-6 = 3; 7-9 = 4; 10 = 5). The results of the questions are used to calculate two summary scores: a Global Physical Health Score and a Global Mental Health score. These scores are then standardized to the general population, using the "T-Score". The average "T-Score" for the United States population is 50 points, with a standard deviation of 10 points. Higher scores are indicative of a healthier patient.
Time frame: Baseline, at last day of radiotherapy (day 3), within 2 weeks after completion of radiotherapy (day 14), 30 days, 90 days, 180 days, and 360 days
Rate of target lesion local control
Time frame: 3 months
Plan to share: Yes — Available data will include de-identified individual participant data collected during the trial.
Supporting information: Study protocol, Sap
This study is active, not recruiting, as verified in Jul 2026. You cannot join it, but the record below documents what was studied.
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Washington University School of Medicine