The purpose of this research study is to test new ways to improve the usefulness of the world's first total-body positron emission tomography (PET)/computed tomography (CT) scanner (EXPLORER) by collecting data from PET scans using one of three different imaging agents: 18F-PSMA; 18F-FES; or, 68Ga DOTATATE. These imaging agents are approved by the FDA to be used for patients diagnosed with prostate cancer (18F-PSMA), neuroendocrine tumor (68Ga DOTATATE), or breast cancer (18F-FES).

18F-PSMA (n=3) and 68Ga-PSMA (n=3)

Inclusion criteria:

• Persons >18 yo with suspected prostate cancer metastasis

• Prior imaging study (CT, and/or MRI and/or Bone scan and/or Fluciclovine scan) suspicious for metastatic disease, obtained within 4 months from the research scan date.

  68Ga DOTATATE (n=3) or 64Cu-DOTATATE (n=3)

Inclusion Criteria:

• Persons > 18 yo suspicious for or diagnosed with somatostatin receptor positive neuroendocrine tumors (NETs)
• Prior DOTATATE PET/CT scan suspicious for tumor obtained not earlier than 4 months from the research scan date.

Exclusion Criteria:

• Recent administration of long-acting somatostatin analogs

Exclusion Criteria for all participants:

• Adults unable to consent
• Pregnant/lactating persons
• Prisoners
• Unable to lie supine for up to 90 minutes at different timepoints in the PET scanner
• Uncontrolled claustrophobia
• Any significant medical condition that in the opinion of the investigator would prevent the participant from participating and/or adhering to study related procedures or interfere with participant safety

Participants will be recruited by physicians, primary care physicians, radiologists, and research team members who will identify potential participants and notify a research team member to assist with consenting. The research team will also screen potential patients from the oncology clinical schedules. When a potential participant is identified, a member of the research team will contact the referring physician and/or a clinical team member in charge of the patient's care and request permission to contact the patient. If the referring physician/clinical team agrees, a member of the research team will contact the patient.