Interesting Image

Almost Complete Response with a Single Administration 225Ac-DOTATATE in a Patient with a Metastatic Neuroendocrine Tumor of Unknown Primary


  • Nalan Alan Selçuk
  • Emre Demirci
  • Meltem Ocak
  • Türkay Toklu
  • Selçuk Ergen
  • Levent Kabasakal

Received Date: 30.07.2021 Accepted Date: 07.01.2022 Mol Imaging Radionucl Ther 2022;31(2):139-141 PMID: 35771003

Neuroendocrine tumors (NETs) are being seen increasingly frequently, and the only known curative treatment method is surgical resection. Peptide receptor radionuclide therapy (PRRT) is a treatment option that the most contributes to progression-free survival and overall survival in metastatic cases.β-emitting radionuclides are traditionally used for PRRT. Nowadays, alpha particle-emitting radionuclides are being developed, with advantages in terms of very high energy and a short path length, which should theoretically show higher efficacy. In this case; in a patient with NET diagnosis who had multiple (>50) lesions in the abdomen, almost all the lesions disappeared with a single dose application. This paper aims to present a case in which we observed the efficacy of 225Ac-DOTATATE treatment, which is an alpha treatment.

Keywords: 225Ac targeted alpha therapy, neuroendocrine tumors, peptide receptor radionuclide therapy


Informed Consent: Obtained from the patient.

Peer-review: Externally and internally peer-reviewed.

Authorship Contributions

Surgical and Medical Practices: L.K., N.A.S., E.D., Concept: L.K., Design: N.A.S., E.D., Data Collection or Processing: E.D., T.T., M.O., S.E., Analysis or Interpretation: T.T., M.O., Literature Search: T.T., M.O., Writing: L.K., N.A.S., E.D., T.T., M.O.

Conflict of Interest: No conflict of interest was declared by the authors.

Financial Disclosure: The authors declared that this study received no financial support.


  1. Bodei L, Kidd M, Paganelli G, Grana CM, Drozdov I, Cremonesi M, Lepensky C, Kwekkeboom DJ, Baum RP, Krenning EP, Modlin IM. Long-term tolerability of PRRT in 807 patients with neuroendocrine tumours: the value and limitations of clinical factors. Eur J Nucl Med Mol Imaging 2015;42:5-19.
  2. Navalkissoor S, Grossman A. Targeted alpha particle therapy for neuroendocrine tumours: the next generation of peptide receptor radionuclide therapy. Neuroendocrinology 2019;108:256-264.
  3. Nayak TK, Norenberg JP, Anderson TL, Prossnitz ER, Stabin MG, Atcher RW. Somatostatin-receptor-targeted alpha-emitting 213Bi is therapeutically more effective than beta(-)-emitting 177Lu in human pancreatic adenocarcinoma cells. Nucl Med Biol 2007;34:185-193.
  4. Ocak M, Toklu T, Demirci E, Selçuk N, Kabasakal L. Post-therapy imaging of 225Ac-DOTATATE treatment in a patient with recurrent neuroendocrine tumor. Eur J Nucl Med Mol Imaging 2020;47:2711-2712.
  5. Ballal S, Yadav MP, Bal C, Sahoo RK, Tripathi M. Broadening horizons with 225Ac-DOTATATE targeted alpha therapy for gastroenteropancreatic neuroendocrine tumour patients stable or refractory to 177Lu-DOTATATE PRRT: first clinical experience on the efficacy and safety. Eur J Nucl Med Mol Imaging 2020;47:934-946.