How I treat neuroendocrine tumours

Abstract

Neuroendocrine tumours (NETs) constitute a heterogeneous group of neoplasms characterised by variable endocrine activity and somatostatin receptor expression, with the latter allowing the use of targeted therapeutic concepts. Currently accepted treatment strategies for advanced well-differentiated NET include somatostatin analogues octreotide and lanreotide, peptide receptor radionuclide therapy using radiolabelled somatostatin analogues, mammalian target of Rapamycin inhibitor everolimus, tyrosine kinase inhibitor sunitinib, interferon alpha and classical cytostatic, such as streptozotocin-based and temozolomide-based treatment. Indication, use and approval of these treatments differ based on primary tumour origin, grading and symptomatic burden and require an optimised multidisciplinary cooperation of medical oncologists, endocrinologists and nuclear medicine specialists. Interestingly, hot topics in oncology including immunotherapy and use of next-generation-sequencing techniques currently play a minor role for the treatment of NETs. The recent revision of the WHO classification including the recognition of the novel NET G3 category allows for potentially more tailored treatment strategies in the near future. However, this new entity also poses a therapeutic challenge as only limited data are currently available. The present article aims to provide an overview on our personal treatment concepts for advanced NETs with a focus on tumours of gastroenteropancreatic origin.

Keywords: everolimus; midgut neuroendocrine tumours; neuroendocrine tumours; pancreatic neuroendocrine tumours; somatostatin analogs.

Figure 1

A potential treatment approach for well-differentiated neuroendocrine tumours of gastroenteropancreatic origin. We also refer to the recent ESMO 2020 guideline and the guidelines of the ENETS. CAPTEM, capecitabine and temozolomide; GEP-NET, gastroenteropancreatic neuroendocrine tumours; PRRT, peptide receptor radionuclide therapy; SSA, somatostatin analogues; SSR, somatostatin receptor positive; STZ-5FU, streptozotocin and 5-fluorouacil.