Intra-arterial peptide-receptor radionuclide therapy for neuro-endocrine tumour liver metastases:an in-patient randomised controlled trial (LUTIA)

Purpose: Peptide receptor radionuclide therapy (PRRT) using [177Lu]Lu-DOTATATE has been shown to effectively prolong progression free survival in grade 1–2 gastroenteropancreatic neuroendocrine tumours (GEP-NET), but is less efficacious in patients with extensive liver metastases. The aim was to investigate whether tumour uptake in liver metastases can be enhanced by intra-arterial administration of [177Lu]Lu-DOTATATE into the hepatic artery, in order to improve tumour response without increasing toxicity. Methods: Twenty-seven patients with grade 1–2 GEP-NET, and bi-lobar liver metastases were randomized to receive intra-arterial PRRT in the left or right liver lobe for four consecutive cycles. The contralateral liver lobe and extrahepatic disease were treated via a “second-pass” effect and the contralateral lobe was used as the control lobe. Up to three metastases (&gt; 3 cm) per liver lobe were identified as target lesions at baseline on contrast-enhanced CT. The primary endpoint was the tumour-to-non-tumour (T/N) uptake ratio on the 24 h post-treatment [177Lu]Lu-SPECT/CT after the first cycle. This was calculated for each target lesion in both lobes using the mean uptake. T/N ratios in both lobes were compared using paired-samples t-test. Findings: After the first cycle, a non-significant difference in T/N uptake ratio was observed: T/NIA = 17·4 vs. T/Ncontrol = 16·2 (p = 0·299). The mean increase in T/N was 17% (1·17; 95% CI [1·00; 1·37]). Of all patients, 67% (18/27) showed any increase in T/N ratio after the first cycle. Conclusion: Intra-arterial [177Lu]Lu-DOTATATE is safe, but does not lead to a clinically significant increase in tumour uptake.</p

The value of yttrium-90 PET/CT after hepatic radioembolization : a pictorial essay

Introduction: Distribution of microspheres after radioembolization can be accurately visualized using PET/CT. In this pictorial essay, we aim to demonstrate the value of 90Y-PET/CT after radioembolization. Methods: 90Y-PET/CT imaging was routinely performed after radioembolization at our institute. Patients were scanned the same day or the day after treatment, using a scanner with time-of-flight technology. We retrospectively reviewed all 90Y-PET/CTs from patients treated with radioembolization (both glass and resin microspheres) between January 2011 and January 2019. Five cases were selected that are illustrative of the added value of PET/CT after radioembolization. Results: 90Y-PET/CT allows for distribution assessment and dosimetry of 90Y-microspheres. It was used for the assessment of treatment success by visualization of tumor targeting, quantification of the absorbed dose, prediction of complications such as radioembolization-induced liver disease, and determining the required dosage for retreatment. Conclusion: PET/CT is an excellent modality for post-treatment imaging of 90Y-microspheres and could lead to improved dose planning and more personalized treatment