In this E-Learning module, the author provides a comprehensive overview of the classification, clinical presentation, diagnosis, assessment and treatment of gastrointestinal neuroendocrine tumours (NETs). The treatment options are in particular supported by reviewing evidence from the clinical studies for a range of medical, loco-regional and nuclear medicine and radiation options.
NETs are rare, usually slow growing, may secrete hormones, may have somatostatin receptors and can be treated with more than one option. In this module, the author provides a basis of histopathological and clinical classification of NETs and reviews the features of gastrointestinal NETs in terms of various localisations. Furthermore, the author reviews specific and non-specific symptoms in the clinical manifestation and details the biochemical tests. The potential role of novel biomarkers is emphasized as well.
Besides conventional imaging (anatomic and endoscopic) a significant part of the module is dedicated to the molecular imaging. The author first gives details about somatostatin receptors in NETs. In particular, octreoscan reveals the primary in 50-80%and the metastases in 95%of patients. It can predict the response with somatostatin analogues. However, it shows low sensitivity in poorly-differentiated NETs, small duodenal gastrinomas and insulinomas. 18F- FDG – PET is useful for evaluating the extension of the disease. Furthermore, the author provides specificities of PET scans specific for NETs, namely PET with 68Ga-somatostatin analogues, 18F-DOPA PET, 11C 5-HTP PET and combination of PETs for the evaluation of NET heterogeneity. The next chapter is dedicated to novel molecular imaging (imaging with somatostatin receptor antagonists). In particular, one of the strengths of this module is the provision of a very detailed diagnostic algorithm.
The treatment of NETs provides medical control of the patient’s symptoms. The goal is a resection of the tumour primary and if possible, metastatic lesions. The goal of treatment in advanced setting is the control of tumour growth, as well as the improvement and maintenance of patient’s quality of life.
The author provides a state-of-the-art in terms of medical therapy options (somatostatin analogues, interferon-α, molecular targeted therapies and systemic chemotherapy), loco-regional therapy options (radiofrequency ablation, embolization/chemoembolization/radioembolization), and nuclear medicine and radiation therapy (tumour-targeted radioactive therapy, external radiation).
A particular emphasis in the module is devoted to a multidisciplinary team approach to NETs, in terms of an accurate diagnosis and staging, evaluation of performance status and quality of life, consensus agreement on treatment plan, continuous reassessment, discussion and peer review of the individualised treatment plan.
