Peptide Receptor Radionuclide Therapy (PRRT) for the Treatment of Neuroendocrine Tumors

Neuroendocrine tumors (NETs) make up a large range of malignancies that arise from neuroendocrine cells in multiple organs of the body. Hallet et al conducted a large population-based study that demonstrated that 21% of NET patients presented with metastatic disease and another 38% developed metastases after resection of the primary tumor (Hallet et al., 2015). This burden demonstrates the need for effective systemic therapy for advanced NETs. Options for systemic therapy include peptide receptor radionuclide therapy (PRRT).

A need for more prospective series are needed on treatment responses and survival outcomes related to gastroenteropancreatic primary NETs treated with PRRT was identified. Thus the purpose of this study is to collect clinical data related to treatment of gastroenteropancreatic primary NETs s with PRRT. Clinical data related to patient characteristics, treatment responses and survival outcomes related to the treatment of gastroenteropancreatic primary NETs with PRRT and on adverse events and complications related to PRRT treatment will be collected.

• Peptide Receptor Radionuclide Therapy (Procedure): a molecular therapy (also called radioisotope therapy) used to treat a specific type of cancer called neuroendocrine tumors or NETs

Primary outcomes

• Demographics and other patient data [7 years from date of procedure]: (such as age at diagnosis, sex, history of smoking alcohol use and symptoms at the time of diagnosis)
• Tumor specific data [7 years from date of procedure]: Tumor site, tumor grade, stage, presence of tumor necrosis, number of mitoses and percentage of Ki-67 and MIB-1 positive cells (proliferative index)
• Use of somatostatin analogs [7 years from date of procedure]: at the time of PRRT, location, isotope used and dose of isotope for each PRRT
• Biomarker data (chromogranin A and pancreastatin) [7 years from date of procedure]: at the time of diagnosis, before and after the first PRRT, and after the second PRRT were also extracted
• Diagnostic imaging findings [7 years from date of procedure]: prior to PRRT and response after PRRT, date of progression on imaging after PRRT, and status of disease on imaging at the last follow-up were also recorded
• Overall survival (OS) [7 years from date of procedure]: the time from diagnosis to death of any cause.
• Time to progression (TTP) [7 years from date of procedure]: the time from the first PRRT until any progression on diagnostic imaging
• Treatment responses and progression [7 years from date of procedure]: assessed with cross-sectional imaging with either computerized tomography (CT) or magnetic resonance imaging (MRI) or positron emission tomography (PET) or single-photon emission computed tomography (SPECT).
• Response [7 years from date of procedure]: any response of any magnitude
• Disease progression [7 years from date of procedure]: any increase in lesion sizes and/or appearance of new metastatic lesions on diagnostic imaging exams.
• Adverse events [7 years from date of procedure]: will be assessed by the investigator who will determine whether or not the event is related to PRRT or related to progression of disease (gastroenteropancreatic primary NET), and whether or not the event meets serious criteria. AEs related to PRRT will be recorded in the study registry.

Sex: All, ages: 18 Years to any

Inclusion Criteria:

1. > 18 years of age
2. Diagnosed with gastroenteropancreatic primary NET and has consented to undergo PRRT per the treating physician. Specifically:

   * Will consider other primaries on a case by case basis if dotatate scan (+) and meet all other criteria.
   * Metastatic or Locally Advanced AND Inoperable
   * Clear disease progression on Octreotide over less than 3 years (RECIST 1.1)
   * Presence of disease within 24 weeks as identified by PET/CT scans with Ga-68 DOTATATE reporting the Krenning score for low-grade NET and/or PET/CT scans with FDG for transformation to high-grade NET
   * Well differentiated on path - Ki67 < 20%
   * Octreotide positive on pathology (if not documented, acceptable if PET/CT imaging shows lesions with Ga-68 DOTATATE uptakeLabs:

     * Cr. <1.7
     * Hgb >8
     * WBC >2K
     * Plt >75K
     * Bili < 3x normal limit
   * No Octreotide within 30 days of administration.
3. Willing and able to comply with the protocol requirements
4. Able to comprehend and sign the Informed Consent Form in English.

Exclusion Criteria:

* Do not meet the Study Inclusion Criteria laid out in section 6.3

• Alejandro Mejia, MD, Principal investigator, Liver Institute at Methodist Dallas Medical Center