A Novel Polymer-Encapsulated Multi-Imaging Modality Fiducial Marker with Positive Signal Contrast for Image-Guided Radiation Therapy

Li Wang; Jeremiah Sanders; John F Ward; Stephen R Lee; Falk Poenisch; David Michael Swanson; Narayan Sahoo; Xiaorong Ronald Zhu; Jingfei Ma; Rajat J Kudchadker; Seungtaek L Choi; Quynh-Nhu Nguyen; Lauren L Mayo; Shalin J Shah; Steven J Frank

doi:10.3390/cancers16030625

A Novel Polymer-Encapsulated Multi-Imaging Modality Fiducial Marker with Positive Signal Contrast for Image-Guided Radiation Therapy

Cancers (Basel). 2024 Jan 31;16(3):625. doi: 10.3390/cancers16030625.

Authors

Affiliations

¹ Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
² Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
³ Department of Urology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
⁴ Department of Interventional Radiology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
⁵ Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
⁶ Department of Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
⁷ Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.

Abstract

Background: Current fiducial markers (FMs) in external-beam radiotherapy (EBRT) for prostate cancer (PCa) cannot be positively visualized on magnetic resonance imaging (MRI) and create dose perturbation and significant imaging artifacts on computed tomography (CT) and MRI. We report our initial experience with clinical imaging of a novel multimodality FM, NOVA.

Methods: We tested Gold Anchor [G-FM], BiomarC [carbon, C-FM], and NOVA FMs in phantoms imaged with kilovoltage (kV) X-rays, transrectal ultrasound (TRUS), CT, and MRI. Artifacts of the FMs on CT were quantified by the relative streak artifacts level (rSAL) metric. Proton dose perturbations (PDPs) were measured with Gafchromic EBT3 film, with FMs oriented either perpendicular to or parallel with the beam axis. We also tested the performance of NOVA-FMs in a patient.

Results: NOVA-FMs were positively visualized on all 4 imaging modalities tested. The rSAL on CT was 0.750 ± 0.335 for 2-mm reconstructed slices. In F-tests, PDP was associated with marker type and depth of measurement (p < 10^-6); at 5-mm depth, PDP was significantly greater for the G-FM (12.9%, p = 10^-6) and C-FM (6.0%, p = 0.011) than NOVA (4.5%). EBRT planning with MRI/CT image co-registration and daily alignments using NOVA-FMs in a patient was feasible and reproducible.

Conclusions: NOVA-FMs were positively visible and produced less PDP than G-FMs or C-FMs. NOVA-FMs facilitated MRI/CT fusion and identification of regions of interest.

Keywords: NOVA; fiducial marker; magnetic resonance imaging; prostate cancer; radiation therapy.

Grants and funding

This research was supported in part by Cancer Center Support (Core) Grant P30 CA016672 from the US National Cancer Institute, National Institutes of Health, to The University of Texas MD Anderson Cancer Center.