3D Printed Mask for GBM and Brain Mets

Official Title

MRI-based Immobilization and Planning: A Feasibility Study of a Novel Inverse Method for CNS Radiation Therapy


This is a single site, investigator initiated study that aims to explore the feasibility of using a personalized 3D printed immobilization mask for CNS patients undergoing radiation therapy. For the purpose of this study, patients will undergo the standard CT SIM, and MR SIM necessary for radiation therapy, creating the masks from the MRIs. Prior to the start of their treatment, patients will have an additional CT scan with the 3D printed mask to confirm safety and treatment accuracy. Patients will then proceed with their standard radiation therapy, immobilized with the mask. There will be a control group that will be treated with the standard thermoplastic mask, as a comparison measure. Both groups will complete a mask tolerability questionnaire throughout the course of their treatment to capture the level of discomfort patients may feel with either masks.

Trial Description

Primary Outcome:

  • Treatment planning time
  • 3D-mask confection time
  • Inter- and intra-fraction motion
  • Patient reported adverse events and tolerability of mask
Secondary Outcome:
  • Gamma values and histograms for MRI-based plans

All patients referred for radiation therapy have had a previous diagnostic imaging study (CT-scan or more commonly MRI) showing the disease at the central nervous system (CNS). Moreover, after surgical biopsy or resection, many Centres perform repeated post-operative imaging. Despite all prior imaging, when radiation therapy treatment is decided, all patients undergo another imaging study (CT simulation [CT-sim]) in which patient's head is placed in a reproducible position, and endure a moulding procedure to create a personalized plastic mask for securing the patient's head in a fixed position during the CT acquisition, and reproduced at the subsequent radiation treatment sessions. Typical wait times between moulding, CT-sim and the first radiation treatment is 3-7 days. If a method would be available to accurately recreate the patient's position during diagnostic imaging and reproduce it during radiation treatments without the need for a moulding session or CT-sim, the treatment process can be streamlined and wait times shortened for patients.

Previous studies using 3D printing technology in radiation therapy (such as brachytherapy applicators) have shown that these employed materials are safe for use in clinical settings, and 3D printers can accurately produce devices of various shapes and sizes for clinical use.

In this study, we propose a novel workflow in which patient's position at diagnostic imaging is reproduced with a 3D-printed patient-specific immobilization device, enabling the use of the same diagnostic imaging for planning purposes in lieu of dedicated simulation and moulding sessions, to decrease wait times for patients between diagnostic imaging and start of radiation treatment.

View this trial on ClinicalTrials.gov

Interested in this trial?

Print this page and take it to your doctor to discuss your eligibilty and treatment options. Only your doctor can refer you to a clinical trial.


Canadian Cancer Society

These resources are provided in partnership with the Canadian Cancer Society