Cancer and Metastasis Reviews

, Volume 33, Issue 1, pp 353–359 | Cite as

Gastrointestinal neuroendocrine tumors (NETs): new diagnostic and therapeutic challenges

  • J. P. Castaño
  • A. Sundin
  • H. R. Maecke
  • C. Villabona
  • R. Vazquez-Albertino
  • E. Navarro
  • K. Öberg


This paper summarizes the current understanding of the biology of somatostatin receptor (sst), role of immunotherapy in neuroendocrine tumor (NET), new agents for PPRT, and methods to assess response and clinical benefit in NET. One of the most interesting aspects of sst biology is the recent discovery of truncated variants of the sst5 receptor subtype with unique tissue distribution and response to somatostatin (SST). These truncated receptors are associated with bad patient prognosis, decreased response to SST analogs, and may be new targets for diagnoses and treatment. IFN remains a cost-effective agent, particularly in classic mid gut carcinoids, and there is interest to continue examining immunotherapy's in this disease. PRRT remains a key strategy for treatment and imaging. In addition to the classic agents, there are a series of new agents targeting other receptors such as the incretin receptors (GLP-1R; GIPR) and other G-protein coupled receptors with great potential. With regards to therapy monitoring, the most commonly used criteria are Response Criteria Evaluation in Solid Tumors (RECIST). However, for different reasons, these criteria are not very useful in NET. Incorporation of other criteria such as Choi as well as functional imaging assessment with PET would be of great interest in this area.


Somatostatin Somatostatin receptor Splicing sst5TMD4 Interferon (IFN) Peptide receptor radionucleotide therapy (PRRT) Incretin receptor (GLP-1R; GIPR) RECIST, SWOG, WHO criteria Functional NET imaging PET 


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Copyright information

© Springer Science+Business Media New York 2014

Authors and Affiliations

  • J. P. Castaño
    • 1
  • A. Sundin
    • 2
  • H. R. Maecke
    • 3
  • C. Villabona
    • 4
  • R. Vazquez-Albertino
    • 5
  • E. Navarro
    • 6
  • K. Öberg
    • 7
  1. 1.Department of Cell Biology, Physiology and Immunology, Universidad de Córdoba, Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC) and Hospital Universitario Reina Sofia; and CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn)CordobaSpain
  2. 2.Department of Molecular Medicine and SurgeryKarolinska University HospitalStockholmSweden
  3. 3.Department of Nuclear MedicineUniversity Hospital FreiburgFreiburgGermany
  4. 4.Department of EndocrinologyHospital Universitario de BellvitgeBarcelonaSpain
  5. 5.Department of Nuclear MedicineHospital Universitario Virgen del RocíoSevillaSpain
  6. 6.Department of Endocrinology and NutritionHospital Universitario Virgen del RocíoSevillaSpain
  7. 7.Department of Endocrine OncologyUppsala UniversityUppsalaSweden

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