Intra-individual qualitative and quantitative comparison of [68Ga]Ga-DOTATATE PET/CT and PET/MRI

Géraldine Lens; Niloefar Ahmadi Bidakhvidi; Vincent Vandecaveye; Steven Grauwels; Annouschka Laenen; Wies Deckers; Ronald Peeters; Raphaëla C Dresen; Jeroen Dekervel; Chris Verslype; Kristiaan Nackaerts; Paul M Clement; Eric Van Cutsem; Michel Koole; Karolien Goffin; Koen Van Laere; Christophe M Deroose

doi:10.1177/17588359231189133

Intra-individual qualitative and quantitative comparison of [⁶⁸Ga]Ga-DOTATATE PET/CT and PET/MRI

Ther Adv Med Oncol. 2023 Oct 24:15:17588359231189133. doi: 10.1177/17588359231189133. eCollection 2023.

Authors

Géraldine Lens¹, Niloefar Ahmadi Bidakhvidi², Vincent Vandecaveye³, Steven Grauwels⁴, Annouschka Laenen⁵, Wies Deckers¹, Ronald Peeters³, Raphaëla C Dresen³, Jeroen Dekervel⁶, Chris Verslype⁶, Kristiaan Nackaerts⁷, Paul M Clement⁸, Eric Van Cutsem⁶, Michel Koole⁹, Karolien Goffin², Koen Van Laere², Christophe M Deroose^{1

10}

Affiliations

¹ Nuclear Medicine, University Hospitals Leuven, Leuven, Belgium.
² Nuclear Medicine, University Hospitals Leuven, Leuven, BelgiumNuclear Medicine and Molecular Imaging, Department of Imaging and Pathology, KU Leuven, Leuven, Belgium.
³ Radiology, University Hospitals Leuven, Leuven, Belgium.
⁴ Radiology, Isala Hospitals, Zwolle, The Netherlands.
⁵ Interuniversity Institute for Biostatistics and Statistical Bioinformatics, Leuven, Belgium.
⁶ Digestive Oncology, University Hospitals Leuven, Leuven, Belgium.
⁷ Respiratory Oncology, University Hospitals Leuven, Leuven, Belgium.
⁸ General Medical Oncology, University Hospitals Leuven, Leuven, Belgium.
⁹ Nuclear Medicine and Molecular Imaging, Department of Imaging and Pathology, KU Leuven, Leuven, Belgium.
¹⁰ Nuclear Medicine and Molecular Imaging, Department of Imaging and Pathology, KU Leuven, Herestraat 49, 3000 Leuven, Flanders, Belgium.

Abstract

Background: Somatostatin receptor (SSTR) positron emission tomography (PET) is a cornerstone of neuroendocrine tumor (NET) management. Hybrid PET/magnetic resonance imaging (MRI) is now available for NET-imaging, next to PET/computed tomography (CT).

Objectives: To determine whether CT or MRI is the best hybrid partner for [⁶⁸Ga]Ga-DOTATATE PET.

Design: Monocentric, prospective study.

Methods: Patients received a same-day [⁶⁸Ga]Ga-DOTATATE PET/CT and subsequent PET/MRI, for suspicion of NET, (re)staging or peptide receptor radionuclide therapy-selection. The union (PET_union) of malignant lesions detected on PET_CT and PET_MRI was the reference standard. Concordance of detection of malignant lesions in an organ was measured between PET_union and CT and PET_union and MRI. Seven bins were used to categorize the number of malignant lesions, containing following ordinal variables: 0, 1, 2-5, 6-10, 11-20, >20 countable and diffuse/uncountable. The difference in number of malignant lesions was obtained as the difference in bin level ('Δbin') between PET_union and CT and PET_union and MRI with a Δbin closer to zero implying a higher concordance rate.

Results: Twenty-nine patients were included. Primary tumors included 17 gastroenteropancreatic-NETs, 1 colon neuroendocrine carcinoma, 7 lung-NETs and 2 meningiomas. Patient level concordance with PET_union was 96% for MRI and 67% for CT (p = 0.039). Organ level concordance with PET_union was 74% for MRI and 40% for CT (p < 0.0001). In bone, there was a higher concordance rate for MRI compared to CT, 92% and 33%, respectively (p = 0.016). Overall, a mean Δbin of 0.5 ± 1.1 for PET_union/MRI and 1.4 ± 1.2 for PET_union/CT (p < 0.0001) was noted. In liver, a mean Δbin of 0.0 ± 1.1 for PET_union/MRI and 1.7 ± 1.2 for PET_union/CT was observed (p = 0.0078). In bone, a mean Δbin closer to zero was observed for PET_union/MRI compared to PET_union/CT, 0.6 ± 1.4 and 2.0 ± 1.5, respectively (p = 0.0098).

Conclusions: Compared to SSTR PET/CT, SSTR PET/MRI had a higher patient and organ level concordance for malignant tumoral involvement and number of malignant lesions, with a clear added value in bone and liver specifically.

Keywords: Krenning score; PET/CT; PET/MRI; SSTR; [68Ga]Ga-DOTATATE; neuroendocrine tumor.