Inhale and Exhale Breath Holds to Improve the Radiation Therapy Accuracy in People With Upper Abdominal Cancers

NCT07594691 | Not Yet Recruiting

• 1 other identifier: 26-5095
• Study Type: interventional
• Target: 15
• Locations: 1 country
• Sites: 1

Brief Summary

This is a prospective quality improvement study. The INEX RT P study will prospectively evaluate INEX RT R that optimizes radiation dose delivery to the target while minimizing dose to critical organs at risk (OAR) by treating patients with different phases of breath hold (inhale and exhale) during the same course of SBRT. 15 patients with abdominal cancer whom are expected to achieve a dosimetric advantage from this technique due to OAR proximity to target will be treated using INEX RT. We hypothesize that we can increase the dose to the RT target by at least 10% while simultaneously decreasing or maintaining dose to adjacent critical OARs when using a combination of breath hold positions to purposefully vary the position of OARs during different fractions of the same treatment course when compared to RT treatments planned on a single breath hold phase alone (present standard of care).

Conditions

Abdominal Cancer

Keywords

INEX RT; SBRT; Breath; Breath Hold Immobilization

Outcome Measures

Primary Outcomes (1)

• Total dose to radiation targets and OARs

  Total dose to radiation targets and OARs on standard workflow (FB ITV or exhale/inhale single breath hold phase only) compared to INEX RT. Unit: Gy

  12 Months

Secondary Outcomes (1)

• Positional change between a deep inhale and deep exhale breath hold

  12 Months

Study Arms (1)

Imaging

EXPERIMENTAL

Diagnostic Test: Simulation and treatment imaging

Interventions

Simulation and treatment imaging DIAGNOSTIC_TEST

Obtain inhale and exhale breath hold images planned to split radiation delivery between inhale and exhale breath hold phases. For radiotherapy courses with an odd number of fractions, the phase of breath hold with higher reproducibility or anatomic advantage will be used for the additional fraction of radiotherapy. If during the treatment planning the investigators determine that the patients will benefit from the multiple breath holds technique, the patients will be treated using the composite breath hold plan. Additional one or two cone beam CTs will be obtained on treatment days for all patients using the inhale and exhale breath hold technique.

Imaging

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age ≥ 18
• Any patient undergoing radiation therapy for a cancer lesion in the abdomen in close proximity to OARs that is hypothesized to have differential displacement on inhale and exhale breath hold CT scans of the OAR relative to the tumor.
• Patients need at least 3 fractions of RT
• Critical OARs are within 2 cm of luminal GI structures, chest wall, or previous radiation fields
• Able to receive and understand verbal and written information regarding study and able to give written informed consent

You may not qualify if:

• Inability to perform inhale or exhale breath holds during standard workflow CT simulation evaluation

Sponsors & Collaborators

• University Health Network, Toronto: lead

Study Sites (1)

Princess Margaret Cancer Centre Toronto, Ontario

Toronto, Ontario, M5G 2M9, Canada

Location

Central Study Contacts

Laura Dawson, MD FRCPSC FASTRO FCAHS

CONTACT

416-946-4501; Laura.Dawson@uhn.ca

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: May 13, 2026
• First Posted: May 19, 2026
• Study Start: May 20, 2026
• Primary Completion (Estimated): May 30, 2027
• Study Completion (Estimated): January 30, 2028
• Last Updated: May 19, 2026

Record last verified: 2026-05

Locations

CA (1)