Recent trends in the treatment of well-differentiated endocrine carcinoma of the small bowel

Abstract

Well-differentiated endocrine carcinomas of the small bowel are fairly rare neoplasms that present many clinical challenges. They secrete peptides and neuroamines that may cause carcinoid syndrome. However, many are clinically silent until late presentation with major effects. Initial treatment aims to control carcinoid syndrome with somatostatin analogs. Even if there is metastatic spread, surgical resection of the primitive tumor should be discussed in cases of retractile mesenteritis, small bowel ischemia or subocclusive syndrome in order to avoid any acute complication, in particular at the beginning of somatostatin analog treatment. The choice of treatment depends on the symptoms, general health of the patient, tumor burden, degree of uptake of radionuclide, histological features of the tumor, and tumor growth. Management strategies include surgery for cure (which is rarely achieved) or for cytoreduction, radiological interventions (transarterial embolization or radiofrequency ablation), and chemotherapy (interferon and somatostatin analogs). New biological agent and radionuclide targeted therapies are under investigation. Diffuse and non-evolving lesions should also be simply monitored. Finally, it has to be emphasized that it is of the utmost importance to enroll these patients with a rare disease in prospective clinical trials assessing new therapeutic strategies.

Figure 1

Management algorithm for patients with non metastatic well-differentiated endocrine carcinoma of the small bowel (stage I-III of TNM classification). 5HIAA: 5-hydroxyindoleacetic acid.

Figure 2

Management algorithm for patients with metastatic well-differentiated endocrine carcinoma of the small bowel (stage IV of TNM classification). TAE: Transarterial embolization; TACE: Transarterial chemoembolization; RFA: Radiofrequency ablation; mTOR: Mammalian target of rapamycin; CT: Computed tomography; MRI: Magnetic resonance imaging.