Utility of ¹¹¹indium-pentetreotide scintigraphy in patients with neuroendocrine tumors

Management of neuroendocrine tumor liver metastases

BACKGROUND

Neuroendocrine Tumors (NETs) are a group of tumors that arise from neuroendocrine cells, and are increasing in incidence worldwide. These tumors often metastasize to the liver, and management of these neuroendocrine tumor liver metastases (NELMs) requires a multi-disciplinary approach. We aim to provide a comprehensive update for treatment of NELMs.

METHODS

We completed a comprehensive systemic review of papers involving the diagnosis, treatment, and outcomes of NELMs. We identified 1612 records via Scopus database literature search. Two independent authors reviewed these records, with 318 meeting criteria for inclusion in the final systemic review.

RESULTS

Primary tumor resection with resection of liver metastases is the treatment of choice for patients with NELMs. Liver-directed therapies and liver transplantation can be considered for patients with unresectable liver metastases. Systemic medical therapy is used for managing tumor burden and symptoms caused by NELMs.

CONCLUSIONS

Advancement in liver-directed and targeted systemic therapies provide improved options for patients with unresectable tumors. Given the complexity of NELMs, management of NELMs necessitates multidisciplinary teams at comprehensive health centers.

Multimodality Imaging of Neuroendocrine Tumors

Neuroendocrine tumors are rare solid tumors with an estimated 12,000 people in the United States diagnosed each year. Neuroendocrine tumors can occur in any part of the body. There is a wide spectrum of disease, ranging from slow-growing and indolent tumors found incidentally to highly aggressive malignancies with a poor prognosis. Knowledge of neuroendocrine tumor pathology is essential in the diagnostic workup of these patients. This article focuses on the evaluation, detection, and staging of common neuroendocrine tumors with multiple imaging modalities; the information gained with a multimodality approach is often complementary and leads to image-guided treatment decision making.

Recurrent Adenomatous Neuroendocrine Tumor of the Middle Ear: A Diagnostic Challenge

Middle ear adenomatous neuroendocrine tumor (MEANT) poses a diagnostic challenge. Clinical symptoms are nonspecific. Definite diagnosis is made by histopathological analysis of the tumor after a complete surgical resection based on an extensive computed tomography/magnetic resonance imaging (CT/MRI). Controversial terminology of the neoplasm arises from the differentiation of this tumor composed of both endocrine and exocrine glands. Middle ear (ME) localization is rare and less aggressive than gastrointestinal tract or lung localizations. Nevertheless, clinical and CT/MRI analyses are necessary follow-ups for preventing or detecting recurrence or metastasis. A case of a female patient aged 26 with recurrent middle ear neuroendocrine adenoma is presented herein.

Octreoscan Versus FDG-PET for Neuroendocrine Tumor Staging: A Biological Approach

BACKGROUND

Clinicians may order Octreoscan or positron emission tomography (PET) scan for staging patients with neuroendocrine tumors (NETs). (111)In-Octreoscan (Octreoscan) identifies tumors by radiolabeled targeting of somatostatin receptors, while 18F-fluorodeoxyglucose-positron emission tomography ((18)FDG-PET) measures differential tissue glucose transport. We assessed the sensitivity of both nuclear imaging modalities with pathologic correlation to define the best initial choice for NET staging after standard cross-sectional imaging.

METHODS

We identified all patients diagnosed with NETs of gastrointestinal or pancreatic origin who underwent nuclear imaging staging by Octreoscan and/or PET from 2000 to 2013. Imaging results were correlated with tumor differentiation and grade of pathology specimens.

RESULTS

Imaging and pathology results were identified for 153 patients. Of these, 131 underwent Octreoscan, 43 underwent PET, and 21 patients had both performed. Overall sensitivity of Octreoscan and PET for NET detection was similar (77 vs. 72 %; p = not significant). For well-differentiated NETs, Octreoscan (n = 124) demonstrated sensitivity of 80 vs. 60 % (p = 0.28) for PET (n = 30). For poorly-differentiated NETs, Octreoscan (n = 7) proved significantly less sensitive than PET (n = 13) (57 vs. 100 %; p = 0.02). The sensitivity of Octreoscan versus PET varied similarly when analyzed by WHO tumor grade: Grade 1 (79 vs. 52 %; p = 0.16), Grade 2 (85 vs. 86 %; p = not significant), and Grade 3 (57 vs. 100 %; p = 0.02).

CONCLUSIONS

Tumor differentiation can be used to guide selection of nuclear imaging modalities for staging gastrointestinal and pancreatic NETs. Octreoscan appears more sensitive than (18)FDG-PET for well-differentiated NETs, whereas (18)FDG-PET demonstrates superior sensitivity for poorly-differentiated NETs.