Improved resolution and sensitivity of [¹⁸F]MFBG PET compared with [¹²³I]MIBG SPECT in a patient with a norepinephrine transporter–expressing tumour

Excerpt

The most widely used radiopharmaceutical for molecular imaging targeting the norepinephrine transporter in neuroendocrine tumours is meta-[¹²³I]iodobenzylguanidine ([¹²³I]MIBG). However, [¹²³I]MIBG only allows for planar and SPECT imaging, which has a lower sensitivity and poorer spatial resolution compared with PET. Other disadvantages include the need for a 2-day protocol and thyroid blockade. Due to the lack of clinically available PET ligands for norepinephrine transporter imaging, often PET tracers for other molecular targets are used/recommended, such as gallium-68-labelled somatostatin analogues ([⁶⁸Ga]Ga-DOTA-TATE/-TOC/-NOC) and [¹⁸F]FDOPA [1‐3]. However, to assess suitability for [¹³¹I]MIBG therapy, [¹²³I]MIBG remains the diagnostic agent of choice for this theranostic approach. Moreover, if neural crest tumour patients are considered for peptide receptor radionuclide therapy, addition of norepinephrine transporter imaging to the pre-therapeutic work-up allows evaluating whether [¹³¹I]MIBG or a combination treatment may increase therapeutic efficacy. …