Neuroendocrine cancer is an unusual disease and often goes undetected by routine imaging. The 68Ga-DOTATATE PET scan is a new generation of scans that might have improved sensitivity and resolution specifically for neuroendocrine tumors. The investigators will scan people with this cancer and compare it to other conventional imaging methods to see if it improves patient care.

Eligible participants will undergo baseline assessments at enrollment. Study participants will receive a one-time administration of 68GaDOTATATE and undergo a PET/CT imaging study. Scans will be performed with "negative" oral contrast (e.g. Volumen™ or equivalent), as many NETs involve the GI tract.

Inclusion Criteria:

• Known diagnosis of neuroendocrine tumor
• At least 18 years of age
• Able to provide informed consent
• Karnofsky score greater than 50
• Females of childbearing potential must have a negative pregnancy test at screening/baseline

Exclusion Criteria:

• Serum creatinine >3.0 mg/dL (270 μM/L)
• Hepatic enzyme levels more than 5 times upper limit of normal.
• Known severe allergy or hypersensitivity to IV radiographic contrast.
• Use of any other investigational product or device within 30 days prior to dosing, or known requirement for any other investigational agent prior to completion of all scheduled study assessments.
• Patients with a body weight of 400 pounds or more or not able to enter the bore of the PET/CT scanner due to BMI, because of the compromise in image quality with CT, PET/CT and MRI that will result.
• Inability to lie still for the entire imaging time (e.g. cough, severe arthritis, etc.).
• Inability to complete the needed investigational and standard-of-care imaging examinations due to other reasons (severe claustrophobia, radiation phobia, etc.)
• Recognized concurrent active infection
• Any additional medical condition, serious intercurrent illness, or other extenuating circumstance that, in the opinion of the Investigator, may significantly interfere with study compliance.

Data are primarily imaging data and toxicity data submitted for peer-review publication and US FDA review, but not shared with a public data archive.

patients with known or suspected pulmonary or gastroenteropancreatic (GEP) neuroendocrine tumors (NETS)

Adverse event data were collected for 10 days minimum and up to 3 years, and/or until lost to follow-up. Some patients living outside the local region had limited long term follow-up.

Toxicity data were compiled and individual patient test results pre-and-post-scans were compared. Non-systematic assessment was used for patients with limited long term follow-up.

Long term follow-up of lab values was limited in some patients who lived outside the local region.