Feasibility of Quantitative Diffusion-Weighted Imaging During Intra-Procedural MRI-Guided Brachytherapy of Locally Advanced Cervical and Vaginal Cancers

Authors

Megan C Jacobsen
Bastien Rigaud
Samantha J Simiele
Gaiane M Rauch
Matthew S Ning
Sastry Vedam
Ann H Klopp
R Jason Stafford
Kristy K Brock
Aradhana M Venkatesan

Publication Date

1-1-2023

Journal

Brachytherapy

Abstract

Purpose: To determine the feasibility of quantitative apparent diffusion coefficient (ADC) acquisition during magnetic resonance imaging-guided brachytherapy (MRgBT) using reduced field-of-view (rFOV) diffusion-weighted imaging (DWI).

Methods and materials: T2-weighted (T2w) MR and full-FOV single-shot echo planar (ssEPI) DWI were acquired in 7 patients with cervical or vaginal malignancy at baseline and prior to brachytherapy, while rFOV-DWI was acquired during MRgBT following brachytherapy applicator placement. The gross target volume (GTV) was contoured on the T2w images and registered to the ADC map. Voxels at the GTV's maximum Maurer distance comprised a central sub-volume (GTVcenter). Contour ADC mean and standard deviation were compared between timepoints using repeated measures ANOVA.

Results: ssEPI-DWI mean ADC increased between baseline and prebrachytherapy from 1.03 ± 0.18 10-3 mm2/s to 1.34 ± 0.28 10-3 mm2/s for the GTV (p = 0.06) and from 0.84 ± 0.13 10-3 mm2/s to 1.26 ± 0.25 10-3 mm2/s at the level of the GTVcenter (p = 0.03), consistent with early treatment response. rFOV-DWI during MRgBT demonstrated mean ADC values of 1.28 ± 0.14 10-3 mm2/s and 1.28 ± 0.19 10-3 mm2/s for the GTV and GTVcenter, respectively (p = 0.02 and p = 0.03 relative to baseline). No significant differences were observed between ssEPI-DWI and rFOV-DWI ADC measurements.

Conclusions: Quantitative ADC measurement in the setting of MRI guided brachytherapy implant placement for cervical and vaginal cancers is feasible using rFOV-DWI, with comparable mean ADC comparable to prebrachytherapy ssEPI-DWI, and may enable MRI-guided radiotherapy targeting of low ADC, radiation resistant sub-volumes of tumor.

Keywords

Female, Humans, Vaginal Neoplasms, Brachytherapy, Feasibility Studies, Diffusion Magnetic Resonance Imaging, Reproducibility of Results, Cervical cancer, vaginal cancer, brachytherapy, diffusion-weighted imaging, apparent diffusion coefficient

DOI

10.1016/j.brachy.2023.06.007

PMID

37612174

PMCID

PMC11798583

PubMedCentral® Posted Date

2-5-2025

PubMedCentral® Full Text Version

Author MSS

Published Open-Access

yes