Management of Neuroendocrine Tumors of the Pancreas

Neuroendocrine tumors (NETs) comprise a heterogeneous group of malignancies, with differences in prognosis and effective therapies. Traditionally, NETs have been characterized by tumor grade, site of primary tumor, functional status, and presence of underlying familial syndrome. However, increased feasibility and use of next-generation sequencing and other methodologies have revealed new genomic and epigenetic aberrations. In the past decade, treatment options available for metastatic well-differentiated gastroenteropancreatic NETs have expanded, with the approval of antiangiogenic and mTOR-directed targeted therapies, and our armamentarium of active therapies is likely to further increase. Optimal surgical therapy both for nonfunctional and functional PNETs has become more personalized and strategic to optimize long-term quality of life time. Management of localized metastatic PNET has become a true multidisciplinary management opportunity that all treating physicians should use. Peptide receptor radioligand therapy is an emerging treatment that uses functional imaging to personalize dosimetry to the tumor and avoid nephrotoxicity. Nevertheless, there is a critical need for further biomarkers, particularly multianalyte biomarkers, to aid in prognostication and predict efficacy of therapies. This review contains 1 figure, 1 table, and 72 references. Key Words: carcinoid tumor, islet cell carcinoma, neuroendocrine tumors, pancreatic, surgical management, medical management, metastatic, localized.

Management of Neuroendocrine Tumors of the Pancreas

Neuroendocrine tumors (NETs) comprise a heterogeneous group of malignancies, with differences in prognosis and effective therapies. Traditionally, NETs have been characterized by tumor grade, site of primary tumor, functional status, and presence of underlying familial syndrome. However, increased feasibility and use of next-generation sequencing and other methodologies have revealed new genomic and epigenetic aberrations. In the past decade, treatment options available for metastatic well-differentiated gastroenteropancreatic NETs have expanded, with the approval of antiangiogenic and mTOR-directed targeted therapies, and our armamentarium of active therapies is likely to further increase. Optimal surgical therapy both for nonfunctional and functional PNETs has become more personalized and strategic to optimize long-term quality of life time. Management of localized metastatic PNET has become a true multidisciplinary management opportunity that all treating physicians should use. Peptide receptor radioligand therapy is an emerging treatment that uses functional imaging to personalize dosimetry to the tumor and avoid nephrotoxicity. Nevertheless, there is a critical need for further biomarkers, particularly multianalyte biomarkers, to aid in prognostication and predict efficacy of therapies. This review contains 1 figure, 1 table, and 72 references. Key Words: carcinoid tumor, islet cell carcinoma, neuroendocrine tumors, pancreatic, surgical management, medical management, metastatic, localized.

Small Intestine: Neuroendocrine and Miscellaneous Tumors

Carcinoid tumors are the most common nonduodenal small bowel tumors. Although the diagnosis of any small bowel tumor is challenging, serum tumor markers and specialized imaging can aid in the diagnosis of carcinoid. Localized carcinoids are treated with surgical resection, whereas metastatic tumors are treated with somatostatin analogues, although liver-directed therapies can improve disease-related symptoms. In contrast, small bowel lymphomas are primarily treated with chemotherapy and sometimes radiation, although surgical intervention may be necessary for diagnosis and resection for palliation of symptoms. Furthermore, there are many benign etiologies of small bowel tumors, including adenoma, leiomyoma, and lipoma. The small bowel can also be a site of distant metastases for which surgical management is reserved for the treatment of complications such as bleeding, obstruction, perforation, or pain. This review contains 3 figures, 3 tables and 17 references. Key words: carcinoid tumor, desmoid tumor, locoregional therapy, mesentery, neuroendocrine tumor, small bowel, small bowel lymphoma, somatostatin

Small Intestine: Neuroendocrine and Miscellaneous Tumors

Carcinoid tumors are the most common nonduodenal small bowel tumors. Although the diagnosis of any small bowel tumor is challenging, serum tumor markers and specialized imaging can aid in the diagnosis of carcinoid. Localized carcinoids are treated with surgical resection, whereas metastatic tumors are treated with somatostatin analogues, although liver-directed therapies can improve disease-related symptoms. In contrast, small bowel lymphomas are primarily treated with chemotherapy and sometimes radiation, although surgical intervention may be necessary for diagnosis and resection for palliation of symptoms. Furthermore, there are many benign etiologies of small bowel tumors, including adenoma, leiomyoma, and lipoma. The small bowel can also be a site of distant metastases for which surgical management is reserved for the treatment of complications such as bleeding, obstruction, perforation, or pain. This review contains 3 figures, 3 tables and 17 references. Key words: carcinoid tumor, desmoid tumor, locoregional therapy, mesentery, neuroendocrine tumor, small bowel, small bowel lymphoma, somatostatin