Non-Target Activity Detection by Post-Radioembolization Yttrium-90 PET/CT: Image Assessment Technique and Case Examples

Yung Hsiang Kao; Andrew E H Tan; Richard H G Lo; Kiang Hiong Tay; Bien Soo Tan; Pierce K H Chow; David C E Ng; Anthony S W Goh

doi:10.3389/fonc.2014.00011

Non-Target Activity Detection by Post-Radioembolization Yttrium-90 PET/CT: Image Assessment Technique and Case Examples

Front Oncol. 2014 Feb 3:4:11. doi: 10.3389/fonc.2014.00011. eCollection 2014.

Authors

Yung Hsiang Kao¹, Andrew E H Tan², Richard H G Lo³, Kiang Hiong Tay³, Bien Soo Tan³, Pierce K H Chow⁴, David C E Ng², Anthony S W Goh²

Affiliations

¹ Department of Nuclear Medicine and PET , Singapore General Hospital , Singapore ; Department of Nuclear Medicine, Austin Hospital , Melbourne, VIC , Australia.
² Department of Nuclear Medicine and PET , Singapore General Hospital , Singapore.
³ Department of Diagnostic Radiology , Singapore General Hospital , Singapore.
⁴ Department of General Surgery , Singapore General Hospital , Singapore ; Department of Surgical Oncology , National Cancer Centre Singapore , Singapore ; Office of Clinical Sciences , Duke-NUS Graduate Medical School , Singapore.

Abstract

High resolution yttrium-90 ((90)Y) imaging of post-radioembolization microsphere biodistribution may be achieved by conventional positron emission tomography with integrated computed tomography (PET/CT) scanners that have time-of-flight capability. However, reconstructed (90)Y PET/CT images have high background noise, making non-target activity detection technically challenging. This educational article describes our image assessment technique for non-target activity detection by (90)Y PET/CT, which qualitatively overcomes the problem of background noise. We present selected case examples of non-target activity in untargeted liver, stomach, gallbladder, chest wall, and kidney, supported by angiography and (90)Y bremsstrahlung single-photon emission computed tomography with integrated computed tomography (SPECT/CT) or technetium-99m macroaggregated albumin SPECT/CT.

Keywords: SIR-spheres; bremsstrahlung SPECT/CT; diagnostic reporting technique; non-target activity; selective internal radiation therapy; yttrium-90 PET/CT; yttrium-90 radioembolization; yttrium-90 resin microspheres.