The aim of this study is to evaluate the diagnostic performance and tumor burden of 18F-metafluorobenzylguanidine (18F-MFBG) positron emission tomography (PET) in patients with neuroendocrine tumors mainly in pheochromocytoma and paraganglioma (PPGL) and neuroblastoma (NB).

Pheochromocytoma and paraganglioma (PPGL) and neuroblastoma (NB) highly express norepinephrine transporter (NET) which is targeted by functional analogue of norepinephrine, 131I/123I-MIBG. However, low spatial resolution of 123/131I-MIBG and inaccurate attenuation correction of single photon emission tomography (SPECT/CT) will affect the image quality of MIBG SPECT and lead to poor diagnosis of small lesions. In addition, 123I-MIBG imaging is usually performed at 24 h after injection, while 131I-MIBG is performed at 48 h or even 72 h after injection. The procedure is complicated and takes a long time, which limits clinical application. 18F-labeled MFBG is an ideal tracer to show the expression of NET. Preliminary data show that 18F-MFBG imaging is safe and has favorable biodistribution and kinetics with good targeting of lesions. Patients can undergo PET 0.5 hours after injection without special preparation. Our study will assess the safety profile, image quality and evaluate the diagnostic performance and tumor burden of 18F-MFBG on nural crest tumors including PPGL and NB. Patients with histologically confirmed or clinically suspected neural crest tumor will be prospectively recruited in this study.

Inclusion Criteria:

- The subject has read, signed, and dated an informed consent form (ICF) prior to any study procedures being performed. Patients with histologically confirmed or clinically suspicious neural crest tumor.

For patients with neuroblastoma, subject should have a routine clinical 123I-MIBG scintigraphy (planar + SPECT/CT) performed within 6 months prior to the inclusion visit or scheduled within 3 months after the inclusion visit.

The subject is male or is a nonpregnant, nonlactating female who is either surgically sterile or is post-menopausal. The subject is able and willing to comply with all study procedures as described in the protocol.

Exclusion Criteria:

- Patients are potentially pregnant (serum and urinary hCG test will be performed in women where pregnancy is not excluded) or is breast-feeding.

Patients undergo surgery between the selection and inclusion visit. Patients who are pregnant, may possibly be pregnant, or wish (including their partners) to become pregnant during the study period, or are lactating. Patients who are not suitable to participate in the trial according to researchers.