Dataset Information

Sensitivity of ¹⁸F-fluorodihydrotestosterone PET-CT to count statistics and reconstruction protocol in metastatic castration-resistant prostate cancer.

ABSTRACT:

Objectives

Whole body [¹⁸F]-fluorodihydrotestosterone positron emission tomography ([¹⁸F]FDHT PET) imaging directly targets the androgen receptor and is a promising prognostic and predictive biomarker in metastatic castration-resistant cancer (mCRPC). To optimize [¹⁸F]FDHT PET-CT for diagnostic and response assessment purposes, we assessed how count statistics and reconstruction protocol affect its accuracy, repeatability, and lesion detectability.

Methods

Whole body [¹⁸F]FDHT PET-CT scans were acquired on an analogue PET-CT on two consecutive days in 14 mCRPC patients harbouring a total of 336 FDHT-avid lesions. Images were acquired at 45?min post-injection of 200?MBq [¹⁸F]FDHT at 3?min per bed position. List-mode PET data were split on a count-wise basis, yielding two statistically independent scans with each 50% of counts. Images were reconstructed according to current EANM Research Ltd. (EARL1, 4?mm voxel) and novel EARL2 guidelines (4?mm voxel + PSF). Per lesion, we measured SUVpeak, SUVmax, SUVmean, and contrast-to-noise ratio (CNR). SUV was normalized to dose per bodyweight as well as to the parent plasma input curve integral. Variability was assessed with repeatability coefficients (RCs).

Results

Count reduction increased liver coefficient of variation from 9.0 to 12.5% and from 10.8 to 13.2% for EARL1 and EARL2, respectively. SUVs of EARL2 images were 12.0-21.7% higher than EARL1. SUVs of 100% and 50% count data were highly correlated (R² >?0.98; slope?=?0.97-1.01; ICC?=?0.99-1.00). Intrascan variability was volume-dependent, and count reduction resulted in higher intrascan variability for EARL2 than EARL1 images. Intrascan RCs were lowest for SUVmean (8.5-10.6%), intermediate for SUVpeak (12.0-16.0%), and highest for SUVmax (17.8-22.2%). Count reduction increased test-retest variance non-significantly (p >?0.05) for all SUV types and normalizations. For SUVpeak at 50% of counts, RCs remained ConclusionsReducing [¹⁸F]FDHT PET acquisition time from 3?min to 1.5 per bed position resulted in a repeatability of SUVpeak (bodyweight) remaining ??30%, which is generally acceptable for response monitoring purposes. However, EARL2 reconstruction was more affected, especially for SUVmax whose repeatability tended to exceed 30%. Lesion detectability was only slightly impaired by reducing acquisition time, which might not be clinically relevant in mCRPC.

SUBMITTER: Cysouw MCF

PROVIDER: S-EPMC6667590 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature

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Publications

Sensitivity of <sup>18</sup>F-fluorodihydrotestosterone PET-CT to count statistics and reconstruction protocol in metastatic castration-resistant prostate cancer.

Cysouw Matthijs C F MCF Kramer Gerbrand M GM Heijtel Dennis D Schuit Robert C RC Morris Michael J MJ van den Eertwegh Alfons J M AJM Voortman Jens J Hoekstra Otto S OS Oprea-Lager Daniela E DE Boellaard Ronald R

EJNMMI research 20190730 1

<h4>Objectives</h4>Whole body [<sup>18</sup>F]-fluorodihydrotestosterone positron emission tomography ([<sup>18</sup>F]FDHT PET) imaging directly targets the androgen receptor and is a promising prognostic and predictive biomarker in metastatic castration-resistant cancer (mCRPC). To optimize [<sup>18</sup>F]FDHT PET-CT for diagnostic and response assessment purposes, we assessed how count statistics and reconstruction protocol affect its accuracy, repeatability, and lesion detectability.<h4>Met ...[more]

PMID: 31363939

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Dataset Information

Sensitivity of ¹⁸F-fluorodihydrotestosterone PET-CT to count statistics and reconstruction protocol in metastatic castration-resistant prostate cancer.

Objectives

Methods

Results

Publications

Sensitivity of <sup>18</sup>F-fluorodihydrotestosterone PET-CT to count statistics and reconstruction protocol in metastatic castration-resistant prostate cancer.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Dataset Information

Sensitivity of 18F-fluorodihydrotestosterone PET-CT to count statistics and reconstruction protocol in metastatic castration-resistant prostate cancer.

Objectives

Methods

Results

Publications

Sensitivity of <sup>18</sup>F-fluorodihydrotestosterone PET-CT to count statistics and reconstruction protocol in metastatic castration-resistant prostate cancer.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Sensitivity of ¹⁸F-fluorodihydrotestosterone PET-CT to count statistics and reconstruction protocol in metastatic castration-resistant prostate cancer.