The study is being conducted to evaluate the efficacy, and safety of Lutetium (177Lu) Oxodotreotide Injection in subjects with advanced gastrointestinal pancreatic neuroendocrine tumors.

Inclusion Criteria:

1. Able and willing to provide a written informed consent;
2. 18~75 years old,male or female;
3. ECOG performance status 0 or 1;
4. Unresectable locally advanced or metastatic gastrointestinal neuroendocrine tumors (GEP-NETs) of low and medium grade (G1 or G2) confirmed by histopathology.

Exclusion Criteria:

1. Central nervous system metastasis is known. Patients who have previously received treatment ( radiotherapy or surgery ) for brain metastases and have no clinical symptoms can be enrolled if the pre-randomized pre-imaging is confirmed to be stable for at least 24 weeks;
2. There are clinical symptoms or diseases of the heart that are not well controlled;
3. Diabetes (fasting blood glucose > 2 × ULN) that cannot be well controlled after optimal medical support treatment;
4. Severe urinary incontinence, hydronephrosis, severe micturition dysfunction or indwelling catheter for any reason.