68Ga-DOTA-MGS5 PET/CT in Patients With Advanced Neuroendocrine Tumours

Inclusion Criteria:

* ≥18 years, men and women
* Understanding and provision of signed and dated written informed consent by the patient or legally acceptable representative prior to any study-specific procedures
* Karnofsky performance status \>70
* Histopathologically diagnosed locally advanced or metastatic MTC with calcitonin level \>100 pg/mL after total thyroidectomy or other histologically diagnosed advanced gastroenteropancreatic and bronchopulmonary NET with known metastases
* Patients with an advanced stage of the disease as documented by local or distant metastasis in an alternative imaging procedure such as 68Ga-SSTR-PET/CT or 18F-DOPA-PET/CT, including a contrast enhanced CT performed up to six months before study inclusion
* Male subjects must-agree to use condoms throughout the study period and for 1 month after study termination if their partner is of childbearing potential and is using no contraception. They agree not to donate semen during study period and for 1 month after study termination.
* Women of childbearing potential (WOCBP) must have a negative urine/serum pregnancy test. WOCBP who are sexually active, agree to use highly-effective means of contraception during the study and for at least 6 months post-study treatment. Allowed are accepted and effective non-hormonal methods of contraception and sexual abstinence or vasectomised partners (\>3 months previously). Vasectomy has to be confirmed by two negative semen analyses.

Exclusion Criteria:

* Other known co-existing malignancies except patients with a history of malignant tumours in complete remission \>3 years, with no evidence of recurrence \<5 years
* Participation in any other investigational trial within 3 months of study entry
* Treatment with tyrosine kinase inhibitors within 1 month before study entry
* Organ allograft requiring immunosuppressive therapy
* Renal insufficiency with an eGFR \<30 mL/min/1.72m2
* Higher than grade 2 hematotoxicity (CTC \>2)
* Clinically abnormal ECG (signs of ischemia, high grade ventricular arrhythmia, high grade supra-ventricular arrhythmia)
* Pregnancy, breast-feeding
* Patients with concurrent illnesses or severe infectious diseases that might preclude study completion
* Patients with bladder outflow obstruction or unmanageable urinary incontinence
* Known hypersensitivity to gallium-68 or to any of the excipients of DOTA-MGS5
* Any condition that precludes raised arms position for prolonged imaging purposes
* Prior administration of a radiopharmaceutical within a period corresponding to 8 half-lives of the radionuclide used on such radiopharmaceutical
* Clinically significant illness or clinically relevant trauma within 3 weeks before the administration of the investigational product
* Persons with any kind of dependency on the investigator or employed by the sponsor or investigator
* Persons held in an institution by legal or official order