Dataset Information

Dynamic Characteristics and Predictive Capability of Tumor Voxel Dose-Response Assessed Using ¹⁸F-FDG PET/CT Imaging Feedback.

ABSTRACT:

Purpose

Tumor voxel dose-response matrix (DRM) can be quantified using feedback from serial FDG-PET/CT imaging acquired during radiotherapy. This study investigated the dynamic characteristics and the predictive capability of DRM.

Methods

FDG-PET/CT images were acquired before and weekly during standard chemoradiotherapy with the treatment dose 2 Gy × 35 from 31 head and neck cancer patients. For each patient, deformable image registration was performed between the pretreatment/baseline PET/CT image and each weekly PET/CT image. Tumor voxel DRM was derived using linear regression on the logarithm of the weekly standard uptake value (SUV) ratios for each tumor voxel, such as SUV measured at a dose level normalized to the baseline SUV₀. The dynamic characteristics were evaluated by comparing the DRM_i estimated using a single feedback image acquired at the ith treatment week (i = 1, 2, 3, or 4) to the DRM estimated using the last feedback image for each patient. The predictive capability of the DRM estimated using 1 or 2 feedback images was evaluated using the receiver operating characteristic test with respect to the treatment outcome of tumor local-regional control or failure.

Results

The mean ± SD of tumor voxel SUV measured at the pretreatment and the 1st, 2nd, 3rd, 4th, and last treatment weeks was 6.76 ± 3.69, 5.72 ± 3.43, 3.85 ± 2.22, 3.27 ± 2.25, 2.5 ± 1.79, and 2.23 ± 1.27, respectively. The deviations between the DRM_i estimated using the single feedback image obtained at the ith week and the last feedback image were 0.86 ± 4.87, -0.06 ± 0.3, -0.09 ± 0.17, and -0.09 ± 0.12 for DRM₁, DRM₂, DRM₃, and DRM₄, respectively. The predictive capability of DRM₃ and DRM₄ was significant (p < 0.001). The area under the curve (AUC) was increased with the increase in treatment dose level. The DRMs constructed using the single feedback image achieved an AUC of 0.86~1. The AUC was slightly improved to 0.94~1 for the DRMs estimated using 2 feedback images.

Conclusion

Tumor voxel metabolic activity measured using FDG-PET/CT fluctuated noticeably during the first 2 treatment weeks and obtained a stabilized reduction rate thereafter. Tumor voxel DRM constructed using a single FDG-PET/CT feedback image after the 2nd treatment week (>20 Gy) has a good predictive capability. The predictive capability improved continuously using a later feedback image and marginally improved when two feedback images were applied.

SUBMITTER: Chen S

PROVIDER: S-EPMC9299377 | biostudies-literature | 2022

REPOSITORIES: biostudies-literature

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Publications

Dynamic Characteristics and Predictive Capability of Tumor Voxel Dose-Response Assessed Using <sup>18</sup>F-FDG PET/CT Imaging Feedback.

Chen Shupeng S Qin An A Yan Di D

Frontiers in oncology 20220706

<h4>Purpose</h4>Tumor voxel dose-response matrix (DRM) can be quantified using feedback from serial FDG-PET/CT imaging acquired during radiotherapy. This study investigated the dynamic characteristics and the predictive capability of DRM.<h4>Methods</h4>FDG-PET/CT images were acquired before and weekly during standard chemoradiotherapy with the treatment dose 2 Gy × 35 from 31 head and neck cancer patients. For each patient, deformable image registration was performed between the pretreatment/ba ...[more]

PMID: 35875108

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Dataset Information

Dynamic Characteristics and Predictive Capability of Tumor Voxel Dose-Response Assessed Using ¹⁸F-FDG PET/CT Imaging Feedback.

Purpose

Methods

Results

Conclusion

Publications

Dynamic Characteristics and Predictive Capability of Tumor Voxel Dose-Response Assessed Using <sup>18</sup>F-FDG PET/CT Imaging Feedback.

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Dataset Information

Dynamic Characteristics and Predictive Capability of Tumor Voxel Dose-Response Assessed Using 18F-FDG PET/CT Imaging Feedback.

Purpose

Methods

Results

Conclusion

Publications

Dynamic Characteristics and Predictive Capability of Tumor Voxel Dose-Response Assessed Using <sup>18</sup>F-FDG PET/CT Imaging Feedback.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Dynamic Characteristics and Predictive Capability of Tumor Voxel Dose-Response Assessed Using ¹⁸F-FDG PET/CT Imaging Feedback.