Per-Lesion Assessment of Individual MRI Sequences and 68 Ga-DOTATATE PET in Neuroendocrine Liver Metastases.

Abstract

ObjectivesTo explore magnetic resonance imaging (MRI) and gallium-68 ( 68 Ga)-DOTATATE positron emission tomography (PET) performance in the assessment of neuroendocrine liver metastases (NELMs) on a per-lesion basis, with particular attention to the contribution of individual MRI sequences and assessment of other factors that might influence their detection.Materials and methodsThis observational retrospective study included patients with histologically confirmed neuroendocrine tumors who underwent both contrast-enhanced MRI and 68 Ga-DOTATATE PET within 12 weeks between August 2017 and December 2023. Three readers in consensus assessed individual MRI sequences [diffusion-weighted imaging (DWI), dynamic contrast-enhanced imaging (DCE), and hepatobiliary phase (HBP) imaging when available], entire MRI data set, and PET in random order. The reference standard was histopathology or follow-up imaging. Diagnostic performance metrics were calculated using generalized estimating equations with Bonferroni correction. Correlations were assessed using Pearson correlation coefficients.ResultsA total of 1249 lesions, comprising 1050 metastases, were analyzed in 60 patients (mean age: 64.9±11.5 years; 56.7% male). Compared with PET, MRI demonstrated superior sensitivity (93% vs. 59%, P 20 mm lesions, P ConclusionsMRI outperformed 68 Ga-DOTATATE PET in detecting NELMs, with DWI and HBP providing particularly high sensitivity for small metastases.