Dataset Information

The superior predictive value of ¹⁶⁶Ho-scout compared with ^99mTc-macroaggregated albumin prior to ¹⁶⁶Ho-microspheres radioembolization in patients with liver metastases.

ABSTRACT:

Purpose

As an alternative to technetium-99m-macroaggregated albumin (^99mTc-MAA), a scout dose of holmium-166 (¹⁶⁶Ho) microspheres can be used prior to ¹⁶⁶Ho-radioembolization. The use of identical particles for pre-treatment and treatment procedures may improve the predictive value of pre-treatment analysis of distribution. The aim of this study was to analyze the agreement between ¹⁶⁶Ho-scout and ¹⁶⁶Ho-therapeutic dose in comparison with the agreement between ^99mTc-MAA and ¹⁶⁶Ho-therapeutic dose.

Methods

Two separate scout dose procedures were performed (^99mTc-MAA and ¹⁶⁶Ho-scout) before treatment in 53 patients. First, qualitative assessment was performed by two blinded nuclear medicine physicians who visually rated the agreement between the ^99mTc-MAA, ¹⁶⁶Ho-scout, and ¹⁶⁶Ho-therapeutic dose SPECT-scans (i.e., all performed in the same patient) on a 5-point scale. Second, agreement was measured quantitatively by delineating lesions and normal liver on FDG-PET/CT. These volumes of interest (VOIs) were co-registered to the SPECT/CT images. The predicted absorbed doses (based on ^99mTc-MAA and ¹⁶⁶Ho-scout) were compared with the actual absorbed dose on post-treatment SPECT.

Results

A total of 23 procedures (71 lesions, 22 patients) were included for analysis. In the qualitative analysis, ¹⁶⁶Ho-scout was superior with a median score of 4 vs. 2.5 for ^99mTc-MAA (p?166Ho-scout in comparison with ^99mTc-MAA when evaluating lesion absorbed dose (-?90.3 and 105.3 Gy vs. -?164.1 and 197.0 Gy, respectively). Evaluation of normal liver absorbed dose did not show difference in agreement between both scout doses and ¹⁶⁶Ho-therapeutic dose (-?2.9 and 5.5 Gy vs -?3.6 and 4.1 Gy for ^99mTc-MAA and ¹⁶⁶Ho-scout, respectively).

Conclusions

In this study, ¹⁶⁶Ho-scout was shown to have a superior predictive value for intrahepatic distribution in comparison with ^99mTc-MAA.

SUBMITTER: Smits MLJ

PROVIDER: S-EPMC7075844 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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The superior predictive value of 166Ho-scout compared with 99mTc-macroaggregated albumin prior to 166Ho-microspheres radioembolization in patients with liver metastases.

Smits Maarten L J MLJ Dassen Mathijs G MG Prince Jip F JF Braat Arthur J A T AJAT Beijst Casper C Bruijnen Rutger C G RCG de Jong Hugo W A M HWAM Lam Marnix G E H MGEH

European journal of nuclear medicine and molecular imaging 20190809 4

<h4>Purpose</h4>As an alternative to technetium-99m-macroaggregated albumin (99mTc-MAA), a scout dose of holmium-166 (166Ho) microspheres can be used prior to 166Ho-radioembolization. The use of identical particles for pre-treatment and treatment procedures may improve the predictive value of pre-treatment analysis of distribution. The aim of this study was to analyze the agreement between 166Ho-scout and 166Ho-therapeutic dose in comparison ...[more]

PMID: 31399801

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