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Tow DH, Tran CG, Borbon LC, Ridder M, Li G, Kaemmer CA, Abusada E, Mahalingam AH, Sadanandam A, Chandrasekaran C, Dillon J, Spitz DR, Quelle DE, Chan CHF, Bellizzi A, Howe JR, Ear PH. Inhibition of serotonin biosynthesis in neuroendocrine neoplasm suppresses tumor growth in vivo. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.07.536013. [PMID: 37066322 PMCID: PMC10104152 DOI: 10.1101/2023.04.07.536013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/18/2023]
Abstract
Small bowel neuroendocrine tumors (SBNETs) originate from enterochromaffin cells in the intestine which synthesize and secrete serotonin. SBNETs express high levels of tryptophan hydroxylase 1 (Tph1), a key enzyme in serotonin biosynthesis. Patients with high serotonin level may develop carcinoid syndrome, which can be treated with somatostatin analogues and the Tph1 inhibitor telotristat ethyl in severe cases. Although the active drug telotristat can efficiently reduce serotonin levels, its effect on tumor growth is unclear. This study determined the effect of serotonin inhibition on tumor cell growth in vitro and in vivo . The levels of Tph1 in various neuroendocrine neoplasms (NENs) were determined and the biological effects of Tph1 inhibition in vitro and in vivo using genetic and pharmacologic approaches was tested. Gene and protein expression analyses were performed on patient tumors and cancer cell lines. shRNAs targeting TPH1 were used to create stable knockdown in BON cells. Control and knockdown lines were assessed for their growth rates in vitro and in vivo , angiogenesis potential, serotonin levels, endothelial cell tube formation, tumor weight, and tumor vascularity. TPH1 is highly expressed in SBNETs and many cancer types. TPH1 knockdown cells and telotristat treated cells showed similar growth rates as control cells in vitro . However, TPH1 knockdown cells formed smaller tumors in vivo and tumors were less vascularized. Although Tph1 inhibition with telotristat showed no effect on tumor cell growth in vitro , Tph1 inhibition reduced tumor formation in vivo . Serotonin inhibition in combination with other therapies is a promising new avenue for targeting metabolic vulnerabilities in NENs.
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High-Dose Somatostatin Analogs for the Treatment of Neuroendocrine Neoplasms: where are we Now? Curr Treat Options Oncol 2022; 23:1001-1013. [PMID: 35501552 DOI: 10.1007/s11864-022-00983-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/18/2022] [Indexed: 11/03/2022]
Abstract
OPINION STATEMENT Neuroendocrine tumors (NET) represent a complex and heterogeneous group of malignancies arising from the diffuse endocrine cells and other cells derived from the neural crest. Advanced disease is observed at diagnosis in more than one-third of patients. Somatostatin analogs (SSA) are the cornerstone in advanced well-differentiated NET treatment. Unfortunately, most patients will eventually develop resistance to SSA treatment by different mechanisms that are not fully understood. In some cases of refractory carcinoid syndrome or progressive disease, the increase of SSA dose may help to reach out a symptomatic and/or tumor growth control. The clinical evidence behind above-label SSA administration is limited and should be individualized and discussed patient by patient. Some questions regarding high-dose SSA use are unsolved, such as the optimal dose to use, the frequency of administration, or the need of deepen molecular understanding that could help to adequately select patients for this approach.
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Abstract
Carcinoid syndrome, a paraneoplastic condition linked with the release of multiple humoral factors, affects around 30-40% of patients with well-differentiated neuroendocrine tumours. Carcinoid syndrome has a major and unfavourable impact on patients' quality of life; it raises costs when compared to non-functioning neuroendocrine tumours; and it causes patients' lifestyles to alter, such as food, job, physical activity, and social life. Somatostatin analogues have been the first-line therapy for individuals with neuroendocrine tumours and carcinoid disease for decades. While these drugs give considerable relief from carcinoid syndrome symptoms, clinical progression is unavoidable, necessitating further research into newer treatment measures. Carcinoid tumours are sometimes difficult to diagnose because of their vague or nonspecific symptoms. There have been several advancements in all aspects of carcinoid syndrome, as well as novel therapeutics, in the previous few years. New epidemiological studies show that it is becoming more common; increasing insights into the pathogenesis of its various clinical manifestations and its natural history: definition of prognostic factors; new methods to verify its presence; the development of new drugs to treat its various manifestations, both initially and in somatostatin-refractory cases; and an increased understanding of the pathogenesis, natural history, and management of the disease. An all language literature search was conducted on MEDLINE, COCHRANE, EMBASE, and Google Scholar till November 2021. The following search strings and Medical Subject Headings (MeSH) terms were used: "Recent advances", "Carcinoid syndrome", "Neuroendocrine Neoplasms" and "Carcinoid heart disease". We comprehensively reviewed the literature on the pathogenesis, clinical features, and newer treatment modalities for Carcinoid Syndrome. Recent advancements in research and management have resulted from advances in our understanding of the aetiology of carcinoid syndrome. The development of molecular indicators of aggressiveness improved serum tumour markers, and the molecular aetiology of carcinoid heart disease are all possible because of advances in molecular biology. We conducted a comprehensive review to update knowledge regarding the pathophysiology, diagnostic protocols, and current and newer treatments for carcinoid syndrome, which presently requires a multidisciplinary approach, due to the complexity of the illness's aetiology, diagnosis, and therapy.
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Time to Sustained Improvement in Bowel Movement Frequency with Telotristat Ethyl: Analyses of Phase III Studies in Carcinoid Syndrome. J Gastrointest Cancer 2021; 52:212-221. [PMID: 32146619 PMCID: PMC7714089 DOI: 10.1007/s12029-020-00375-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Background Telotristat ethyl is approved to treat carcinoid syndrome diarrhea in combination with somatostatin analogs. In TELESTAR and TELECAST phase III studies, patients with carcinoid syndrome received telotristat ethyl 250 or 500 mg 3 times per day (tid) or placebo tid in addition to somatostatin analogs. The aim of this prespecified analysis was to examine the time to reductions in bowel movements (BMs) in the TELESTAR and TELECAST studies using survival analysis methods. Methods First occurrence of sustained response was defined as the time to the first day of 2 consecutive weeks with a mean BM frequency improvement of ≥ 30% from baseline during the 12-week double-blind treatment periods. Time to first ≥ 30% worsening in BM frequency was also measured. Treatments were compared with the log-rank test; Cox regression models provided point and confidence interval estimates of the hazard ratios for each trial. Results In TELESTAR and TELECAST, majority of patients (69%) on telotristat ethyl experienced a sustained ≥ 30% improvement in BM frequency. The median time to sustained reduction of at least 30% in BM frequency was significantly faster (fewer days to onset) for telotristat ethyl compared with placebo in both TELESTAR (250 mg, HR = 2.3 [95% CI, 1.3–4.1, P = 0.004]; 500 mg, HR = 2.2 [95% CI, 1.2–3.9, P = 0.009]) and TELECAST (250 mg, HR = 3.9 [95% CI, 1.6–11.1, P = 0.003]; 500 mg, HR = 4.2 [95% CI, 1.7–11.7, P = 0.002]). In TELECAST, 42% of patients on placebo experienced sustained worsening in BM frequency compared with 20% on telotristat ethyl; no significant difference was observed in TELESTAR. Conclusion The time of onset of sustained BM frequency improvement mean and range are important when considering use of telotristat ethyl in patients with carcinoid syndrome diarrhea. Telotristat ethyl may also reduce sustained worsening in BM frequency. Trial Registration ClinicalTrials.gov Identifiers: NCT01677910, NCT02063659
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Kanova M, Kohout P. Serotonin-Its Synthesis and Roles in the Healthy and the Critically Ill. Int J Mol Sci 2021; 22:ijms22094837. [PMID: 34063611 PMCID: PMC8124334 DOI: 10.3390/ijms22094837] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2021] [Revised: 04/25/2021] [Accepted: 04/30/2021] [Indexed: 12/12/2022] Open
Abstract
Serotonin (5-hydroxytryptamine, 5-HT) plays two important roles in humans-one central and the other peripheral-depending on the location of the 5-HT pools of on either side of the blood-brain barrier. In the central nervous system it acts as a neurotransmitter, controlling such brain functions as autonomic neural activity, stress response, body temperature, sleep, mood and appetite. This role is very important in intensive care, as in critically ill patients multiple serotoninergic agents like opioids, antiemetics and antidepressants are frequently used. High serotonin levels lead to altered mental status, deliria, rigidity and myoclonus, together recognized as serotonin syndrome. In its role as a peripheral hormone, serotonin is unique in controlling the functions of several organs. In the gastrointestinal tract it is important for regulating motor and secretory functions. Apart from intestinal motility, energy metabolism is regulated by both central and peripheral serotonin signaling. It also has fundamental effects on hemostasis, vascular tone, heart rate, respiratory drive, cell growth and immunity. Serotonin regulates almost all immune cells in response to inflammation, following the activation of platelets.
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Affiliation(s)
- Marcela Kanova
- Department of Anaesthesiology and Intensive Care Medicine, University Hospital Ostrava, 70852 Ostrava-Poruba, Czech Republic
- Institute of Physiology and Pathophysiology, Faculty of Medicine, University of Ostrava, Syllabova 19, 70300 Ostrava-Vítkovice, Czech Republic
- Correspondence: ; Tel.: +420-59737-2707
| | - Pavel Kohout
- Department of Internal Medicine, 3rd Faculty of Medicine, Charles University Prague and Teaching Thomayer Hospital, 14059 Prague, Czech Republic;
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A literature-based treatment algorithm for low-grade neuroendocrine liver metastases. HPB (Oxford) 2021; 23:63-70. [PMID: 32448647 DOI: 10.1016/j.hpb.2020.04.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Revised: 03/03/2020] [Accepted: 04/20/2020] [Indexed: 12/12/2022]
Abstract
BACKGROUND The optimal timing of treatment of liver metastases from low-grade neuroendocrine tumors (LG-NELM) varies significantly due to numerous treatment modalities and the literature supporting various treatment(s). This study sought to create and validate a literature-based treatment algorithm for LG-NELM. METHODS A treatment algorithm to maximize overall survival (OS) was designed using peer-reviewed articles evaluating treatment of LG-NELM. This algorithm was retrospectively applied to patients treated for LG-NELM at our institution. Deviation was determined based on whether or not a patient received treatment consistent with that recommended by the algorithm. Patients who did and did not deviate from the algorithm were compared with respect to OS and number of treatments. RESULTS Applying our algorithm to a 149-patient cohort, 57 (38%) deviated from recommended treatment. Deviation occurred in the form of alternative (28, 49%) versus additional procedures (29, 51%). Algorithm deviators underwent significantly more procedures than non-deviators (median 1 vs. 2, p < 0.001). Cox model indicated no difference in OS associated with algorithm deviation (HR 1.19, p = 0.58) when controlling for age and tumor characteristics. CONCLUSION This literature-based algorithm helps standardize treatment protocols in patients with LG-NELM and can reduce cost and risk by minimizing unnecessary procedures. Prospective implementation and validation is required.
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Pusceddu S, Rossi RE, Torchio M, Prinzi N, Niger M, Coppa J, Giacomelli L, Sacco R, Facciorusso A, Corti F, Raimondi A, Prisciandaro M, Colombo E, Beninato T, Del Vecchio M, Milione M, Di Bartolomeo M, de Braud F. Differential Diagnosis and Management of Diarrhea in Patients with Neuroendocrine Tumors. J Clin Med 2020; 9:E2468. [PMID: 32752158 PMCID: PMC7464810 DOI: 10.3390/jcm9082468] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 07/22/2020] [Accepted: 07/26/2020] [Indexed: 02/07/2023] Open
Abstract
Diarrhea is a recurrent symptom in patients with neuroendocrine tumors (NETs) and can represent different etiologies; thus, differential diagnosis is challenging. This paper distinguishes the different causes of chronic diarrhea in patients with gastroenteropancreatic NETs, with the aim to identify the most appropriate therapeutic approach. Underlying causes of diarrhea can be multifactorial, including not only diarrhea that is related to specific hormonal hypersecretory syndromes, but also diarrhea that is secondary to the following: extensive surgery which can cause pancreatic exocrine insufficiency or short bowel syndrome, treatment with somatostatin analogs or other antineoplastic agents, and bile acid malabsorption. After initial management of diarrhea with general treatments (dietary modification, use of antidiarrheals), a proper differential diagnosis is necessary to treat patients with specific etiology-driven therapeutic approaches, such as somatostatin analogs, pancreatic enzyme replacement therapy, and tryptophan hydroxylase inhibitors. In conclusion, NETs should be considered in the differential diagnosis of patients suffering from chronic diarrhea, after the exclusion of more common etiologies. Furthermore, physicians should keep in mind that several different etiologies might be responsible for diarrhea occurrence in NET patients. A prompt diagnosis of the actual cause of diarrhea is necessary to guide the treatment and a multidisciplinary approach is mandatory.
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Affiliation(s)
- Sara Pusceddu
- Department of Medical Oncology, Gastro-entero-pancreatic and Neuroendocrine Unit 1, ENETS Center of Excellence, Fondazione IRCCS Istituto Nazionale dei Tumori, Via Venezian 1, 20133 Milan, Italy; (M.T.); (N.P.); (M.N.); (F.C.); (A.R.); (M.P.); (E.C.); (T.B.); (M.D.B.); (F.d.B.)
| | - Roberta Elisa Rossi
- Gastro-intestinal Surgery and Liver Transplantation Unit, Fondazione IRCCS Istituto Nazionale dei Tumori, 20133 Milan, Italy; (R.E.R.); (J.C.)
- Department of Pathophysiology and Organ Transplant, Università degli Studi di Milano, 20122 Milan, Italy
| | - Martina Torchio
- Department of Medical Oncology, Gastro-entero-pancreatic and Neuroendocrine Unit 1, ENETS Center of Excellence, Fondazione IRCCS Istituto Nazionale dei Tumori, Via Venezian 1, 20133 Milan, Italy; (M.T.); (N.P.); (M.N.); (F.C.); (A.R.); (M.P.); (E.C.); (T.B.); (M.D.B.); (F.d.B.)
| | - Natalie Prinzi
- Department of Medical Oncology, Gastro-entero-pancreatic and Neuroendocrine Unit 1, ENETS Center of Excellence, Fondazione IRCCS Istituto Nazionale dei Tumori, Via Venezian 1, 20133 Milan, Italy; (M.T.); (N.P.); (M.N.); (F.C.); (A.R.); (M.P.); (E.C.); (T.B.); (M.D.B.); (F.d.B.)
| | - Monica Niger
- Department of Medical Oncology, Gastro-entero-pancreatic and Neuroendocrine Unit 1, ENETS Center of Excellence, Fondazione IRCCS Istituto Nazionale dei Tumori, Via Venezian 1, 20133 Milan, Italy; (M.T.); (N.P.); (M.N.); (F.C.); (A.R.); (M.P.); (E.C.); (T.B.); (M.D.B.); (F.d.B.)
| | - Jorgelina Coppa
- Gastro-intestinal Surgery and Liver Transplantation Unit, Fondazione IRCCS Istituto Nazionale dei Tumori, 20133 Milan, Italy; (R.E.R.); (J.C.)
| | - Luca Giacomelli
- Polistudium SRL, 20135 Milan, Italy;
- Department of Surgical Sciences and Integrated Diagnostics, University of Genoa, 16126 Genoa, Italy
| | - Rodolfo Sacco
- Department of Medical Sciences, Section of Gastroenterology, University of Foggia, 71122 Foggia, Italy; (R.S.); (A.F.)
| | - Antonio Facciorusso
- Department of Medical Sciences, Section of Gastroenterology, University of Foggia, 71122 Foggia, Italy; (R.S.); (A.F.)
| | - Francesca Corti
- Department of Medical Oncology, Gastro-entero-pancreatic and Neuroendocrine Unit 1, ENETS Center of Excellence, Fondazione IRCCS Istituto Nazionale dei Tumori, Via Venezian 1, 20133 Milan, Italy; (M.T.); (N.P.); (M.N.); (F.C.); (A.R.); (M.P.); (E.C.); (T.B.); (M.D.B.); (F.d.B.)
| | - Alessandra Raimondi
- Department of Medical Oncology, Gastro-entero-pancreatic and Neuroendocrine Unit 1, ENETS Center of Excellence, Fondazione IRCCS Istituto Nazionale dei Tumori, Via Venezian 1, 20133 Milan, Italy; (M.T.); (N.P.); (M.N.); (F.C.); (A.R.); (M.P.); (E.C.); (T.B.); (M.D.B.); (F.d.B.)
| | - Michele Prisciandaro
- Department of Medical Oncology, Gastro-entero-pancreatic and Neuroendocrine Unit 1, ENETS Center of Excellence, Fondazione IRCCS Istituto Nazionale dei Tumori, Via Venezian 1, 20133 Milan, Italy; (M.T.); (N.P.); (M.N.); (F.C.); (A.R.); (M.P.); (E.C.); (T.B.); (M.D.B.); (F.d.B.)
| | - Elena Colombo
- Department of Medical Oncology, Gastro-entero-pancreatic and Neuroendocrine Unit 1, ENETS Center of Excellence, Fondazione IRCCS Istituto Nazionale dei Tumori, Via Venezian 1, 20133 Milan, Italy; (M.T.); (N.P.); (M.N.); (F.C.); (A.R.); (M.P.); (E.C.); (T.B.); (M.D.B.); (F.d.B.)
| | - Teresa Beninato
- Department of Medical Oncology, Gastro-entero-pancreatic and Neuroendocrine Unit 1, ENETS Center of Excellence, Fondazione IRCCS Istituto Nazionale dei Tumori, Via Venezian 1, 20133 Milan, Italy; (M.T.); (N.P.); (M.N.); (F.C.); (A.R.); (M.P.); (E.C.); (T.B.); (M.D.B.); (F.d.B.)
| | - Marta Del Vecchio
- Unit of Pharmacy, Fondazione IRCCS Istituto Nazionale dei Tumori, 20133 Milan, Italy;
| | - Massimo Milione
- Department of Pathology and Laboratory Medicine, Fondazione IRCCS–Istituto Nazionale dei Tumori, 20133 Milan, Italy;
| | - Maria Di Bartolomeo
- Department of Medical Oncology, Gastro-entero-pancreatic and Neuroendocrine Unit 1, ENETS Center of Excellence, Fondazione IRCCS Istituto Nazionale dei Tumori, Via Venezian 1, 20133 Milan, Italy; (M.T.); (N.P.); (M.N.); (F.C.); (A.R.); (M.P.); (E.C.); (T.B.); (M.D.B.); (F.d.B.)
| | - Filippo de Braud
- Department of Medical Oncology, Gastro-entero-pancreatic and Neuroendocrine Unit 1, ENETS Center of Excellence, Fondazione IRCCS Istituto Nazionale dei Tumori, Via Venezian 1, 20133 Milan, Italy; (M.T.); (N.P.); (M.N.); (F.C.); (A.R.); (M.P.); (E.C.); (T.B.); (M.D.B.); (F.d.B.)
- Oncology and Hematology-Oncology Department, University of Milan, 20122 Milan, Italy
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Abstract
The rate-limiting enzyme in serotonin synthesis is tryptophan hydroxylase (TPH). There are two independent serotonin systems in the body characterized by two isoforms of TPH, TPH1 and TPH2. While TPH2 synthesizes serotonin in the brain, TPH1 is expressed in the gut and in other peripheral tissues and supplies platelets in the circulation with serotonin. This duality of the serotonin system is enforced by the blood-brain barrier which is impermeable for serotonin. In the brain serotonin acts as neurotransmitter and is a main target for the treatment of psychiatric disorders. In the periphery it is released by platelets at the site of activation and elicits numerous physiological effects. TPH1 deficient mice were shown to be protected from diverse diseases including hemostatic, inflammatory, fibrotic, gastrointestinal, and metabolic disorders and therefore serotonin synthesis inhibition emerged as a reasonable therapeutic paradigm. Recently the first TPH inhibitor, telotristat ethyl, came on the market for the treatment of carcinoid syndrome. This review summarizes the state of development and the therapeutic opportunities of such compounds.
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Affiliation(s)
- Michael Bader
- Max-Delbrück Center for Molecular Medicine (MDC), Robert-Rössle-Str. 10, 13125 Berlin-Buch, Germany; University of Lübeck, Institute for Biology, Ratzeburger Allee 160, 23562 Lübeck, Germany; Charité University Medicine, Charitéplatz 1, 10117 Berlin, Germany; German Center for Cardiovascular Research (DZHK), Partner Site, Berlin, Germany.
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Scotton WJ, Hill LJ, Williams AC, Barnes NM. Serotonin Syndrome: Pathophysiology, Clinical Features, Management, and Potential Future Directions. Int J Tryptophan Res 2019; 12:1178646919873925. [PMID: 31523132 PMCID: PMC6734608 DOI: 10.1177/1178646919873925] [Citation(s) in RCA: 72] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Accepted: 08/13/2019] [Indexed: 12/18/2022] Open
Abstract
Serotonin syndrome (SS) (also referred to as serotonin toxicity) is a potentially life-threatening drug-induced toxidrome associated with increased serotonergic activity in both the peripheral (PNS) and central nervous systems (CNS). It is characterised by a dose-relevant spectrum of clinical findings related to the level of free serotonin (5-hydroxytryptamine [5-HT]), or 5-HT receptor activation (predominantly the 5-HT1A and 5-HT2A subtypes), which include neuromuscular abnormalities, autonomic hyperactivity, and mental state changes. Severe SS is only usually precipitated by the simultaneous initiation of 2 or more serotonergic drugs, but the syndrome can also occur after the initiation of a single serotonergic drug in a susceptible individual, the addition of a second or third agent to long-standing doses of a maintenance serotonergic drug, or after an overdose. The combination of a monoamine oxidase inhibitor (MAOI), in particular MAO-A inhibitors that preferentially inhibit the metabolism of 5-HT, with serotonergic drugs is especially dangerous, and may lead to the most severe form of the syndrome, and occasionally death. This review describes our current understanding of the pathophysiology, clinical presentation and management of SS, and summarises some of the drugs and interactions that may precipitate the condition. We also discuss the newer novel psychoactive substances (NPSs), a growing public health concern due to their increased availability and use, and their potential risk to evoke the syndrome. Finally, we discuss whether the inhibition of tryptophan hydroxylase (TPH), in particular the neuronal isoform (TPH2), may provide an opportunity to pharmacologically target central 5-HT synthesis, and so develop new treatments for severe, life-threatening SS.
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Affiliation(s)
- William J Scotton
- Department of Neurology, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
| | - Lisa J Hill
- Institute of Clinical Sciences, University of Birmingham, Birmingham, UK
| | - Adrian C Williams
- Department of Neurology, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
| | - Nicholas M Barnes
- Institute of Clinical Sciences, University of Birmingham, Birmingham, UK
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Naraev BG, Halland M, Halperin DM, Purvis AJ, O'Dorisio TM, Halfdanarson TR. Management of Diarrhea in Patients With Carcinoid Syndrome. Pancreas 2019; 48:961-972. [PMID: 31425482 PMCID: PMC6867674 DOI: 10.1097/mpa.0000000000001384] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Accepted: 07/10/2019] [Indexed: 02/06/2023]
Abstract
Neuroendocrine tumors (NETs) arise from enterochromaffin cells found in neuroendocrine tissues, with most occurring in the gastrointestinal tract. The global incidence of NETs has increased in the past 15 years, likely due to better diagnostic methods. Small-bowel NETs are frequently associated with carcinoid syndrome (CS). Carcinoid syndrome diarrhea occurs in 80% of CS patients and poses a substantial symptomatic and economic burden. Patients with CS diarrhea frequently suffer from diarrhea and flushing and report corresponding impairment in quality of life, requiring substantial changes in daily activities and lifestyle. Treatment paradigms range from surgical debulking to liver-directed therapies to treatment with somatostatin analogs, nonspecific anti-diarrheal agents, and a tryptophan hydroxylase inhibitor. Other causes of diarrhea, including steatorrhea, short bowel syndrome, and bile acid malabsorption, should be considered in NET patients with refractory diarrhea. More therapeutic options are needed for symptomatic management of patients with NETs, and better understanding of the pathophysiology can empower clinicians with improved patient care.
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Affiliation(s)
| | - Magnus Halland
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, MN
| | - Daniel M. Halperin
- Department of Gastrointestinal Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX
| | - Amy J. Purvis
- University of Arizona Cancer Center (UACC), Phoenix, AZ
| | - Thomas M. O'Dorisio
- Neuroendocrine Cancer Program, University of Iowa Health Care, Iowa City, IA
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Saavedra C, Barriuso J, McNamara MG, Valle JW, Lamarca A. Spotlight on telotristat ethyl for the treatment of carcinoid syndrome diarrhea: patient selection and reported outcomes. Cancer Manag Res 2019; 11:7537-7556. [PMID: 31496810 PMCID: PMC6690650 DOI: 10.2147/cmar.s181439] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Accepted: 06/21/2019] [Indexed: 12/12/2022] Open
Abstract
Neuroendocrine tumors (NETs) are rare cancers with an associated prolonged survival in some patients. A proportion of patients diagnosed with NETs will present with carcinoid syndrome symptoms, characterized by diarrhea, flushing and/or wheezing. This review summarizes the current treatment options for carcinoid syndrome, focusing on the latest novel treatment option, telotristat ethyl. In addition, information on patient-reported outcomes and impact of carcinoid syndrome on quality of life (QOL) and improvement of following treatment with telotristat ethyl are reviewed. This article also provides an overview of the current QOL questionnaires for patients with NETs and addresses unmet needs in this field of patient-reported outcomes.
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Affiliation(s)
- Cristina Saavedra
- Medical Oncology Department, The Christie NHS Foundation Trust, Manchester, UK.,Medical Oncology Department, Ramon Y Cajal University Hospital, Madrid, Spain
| | - Jorge Barriuso
- Medical Oncology Department, The Christie NHS Foundation Trust, Manchester, UK.,Division of Cancer Sciences, University of Manchester, Manchester, UK
| | - Mairéad G McNamara
- Medical Oncology Department, The Christie NHS Foundation Trust, Manchester, UK.,Division of Cancer Sciences, University of Manchester, Manchester, UK
| | - Juan W Valle
- Medical Oncology Department, The Christie NHS Foundation Trust, Manchester, UK.,Division of Cancer Sciences, University of Manchester, Manchester, UK
| | - Angela Lamarca
- Medical Oncology Department, The Christie NHS Foundation Trust, Manchester, UK.,Division of Cancer Sciences, University of Manchester, Manchester, UK
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Molina-Cerrillo J, Grande E, Alonso-Gordoa T. Inhibition of Serotonin Synthesis May Have Antitumor Activity? Long-Term Efficacy in a Patient with Gastrointestinal Neuroendocrine Tumor. Oncologist 2019; 24:e597-e599. [PMID: 30877189 DOI: 10.1634/theoncologist.2018-0776] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Accepted: 02/20/2019] [Indexed: 12/14/2022] Open
Abstract
In this article, we propose, based on a clinical case, the potential antitumor effect related to the inhibition of serotonin in neuroendocrine tumors (NETs). Currently, the only drug that exists for the symptomatic treatment of carcinoid syndrome refractory to somatostatin analogues is telotristat, based on its pivotal study, the TELESTAR trial. Based on the existing preclinical rationale, it seems that the inhibition of serotonin may have an antitumoral role in NETs. Briefly, serotonin may act as an autocrine growth factor of NETs, and it may also play an immunomodulatory role by enhancing macrophage polarization to an immunotolerant M2 phenotype. To our knowledge, this rationale for the possible antitumor effect of serotonin in NETs has not yet been published in the literature.
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Affiliation(s)
| | - Enrique Grande
- Medical Oncology Department, MD Cancer Center, Madrid, Spain
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13
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Abstract
Neuroendocrine tumors, including carcinoids, are rare and insidiously growing tumors. Related to their site of origin, tumors can be functional, causing various forms of the carcinoid syndrome, owing to the overproduction of serotonin, histamine, or other bioactive substances. They often invade adjacent structures or metastasize to the liver and elsewhere. Treatment includes multimodal approaches, including cytoreductive surgery, locoregional embolization, cytotoxic therapy, peptide receptor radionuclide therapy, and various targeted therapies with goals of symptom relief and control of tumor growth. This article summarizes current and emerging approaches to management and reviews several promising future therapies.
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Affiliation(s)
- Paul Benjamin Loughrey
- Department of Ophthalmology, Royal Victoria Hospital, Belfast Trust, Grosvenor Road, Belfast, BT12 6BA, UK; Department of Endocrinology and Diabetes, Royal Victoria Hospital, Belfast Trust, Grosvenor Road, Belfast, BT12 6BA, UK
| | - Dongyun Zhang
- Department of Medicine, David Geffen School of Medicine, University of California, 700 Tiverton Avenue, Los Angeles, CA 90095, USA
| | - Anthony P Heaney
- Department of Medicine, David Geffen School of Medicine, University of California, 700 Tiverton Avenue, Los Angeles, CA 90095, USA; Department of Neurosurgery, David Geffen School of Medicine, University of California, 700 Tiverton Avenue, Los Angeles, CA 90095, USA.
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14
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Jin XF, Spampatti MP, Spitzweg C, Auernhammer CJ. Supportive therapy in gastroenteropancreatic neuroendocrine tumors: Often forgotten but important. Rev Endocr Metab Disord 2018; 19:145-158. [PMID: 29464446 DOI: 10.1007/s11154-018-9443-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Neuroendocrine tumors (NETs) are a group of rare and heterogeneous malignancies that can develop in various organs. A significant number of gastroenteropancreatic neuroendocrine tumours (GEP-NETs) is functionally active and presents with symptoms related to the secretion of biologically active substances, leading to the development of distinct clinical syndromes. There are various therapeutic approaches for GEP-NETs, including curative surgery, palliative surgery, local-ablative and loco-regional therapies as well as systemic therapeutic options including peptide receptor radionuclide therapy, cytotoxic therapy, and molecularly targeted therapies. Specific supportive therapy of patients with NETs includes management or prevention of hormone-related clinical syndromes and paraneoplastic states. Supportive therapy plays a key role in NET treatment. Supportive therapy includes debulking surgery and interventional radiologic techniques to reduce tumour bulk or load, as well as systemic medical treatment options to manage or prevent hypersecretion syndromes and treatment-related side effects. Supportive therapies are a type of of comprehensive treatment addressing the patient as a whole person throughout the process of NET treatment. Therefore, supportive therapy also encompasses psychosocial support, expert nursing, nutritional support and management of cancer related pain.
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Affiliation(s)
- Xi-Feng Jin
- Department of Internal Medicine IV, University-Hospital Campus Grosshadern, Ludwig-Maximilian University of Munich, Munich, Germany
| | - Matilde P Spampatti
- Department of Internal Medicine II, University-Hospital Campus Grosshadern, Ludwig-Maximilian University of Munich, Munich, Germany
- Interdisciplinary Center of Neuroendocrine Tumours of the GastroEnteroPancreatic System (GEPNET-KUM), Klinikum der Universitaet Muenchen, Ludwig-Maximilians-University of Munich, Campus Grosshadern, Marchioninistr, 15, 81377, Munich, Germany
| | - Christine Spitzweg
- Department of Internal Medicine IV, University-Hospital Campus Grosshadern, Ludwig-Maximilian University of Munich, Munich, Germany
- Interdisciplinary Center of Neuroendocrine Tumours of the GastroEnteroPancreatic System (GEPNET-KUM), Klinikum der Universitaet Muenchen, Ludwig-Maximilians-University of Munich, Campus Grosshadern, Marchioninistr, 15, 81377, Munich, Germany
| | - Christoph J Auernhammer
- Department of Internal Medicine IV, University-Hospital Campus Grosshadern, Ludwig-Maximilian University of Munich, Munich, Germany.
- Interdisciplinary Center of Neuroendocrine Tumours of the GastroEnteroPancreatic System (GEPNET-KUM), Klinikum der Universitaet Muenchen, Ludwig-Maximilians-University of Munich, Campus Grosshadern, Marchioninistr, 15, 81377, Munich, Germany.
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15
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Matthes S, Bader M. Peripheral Serotonin Synthesis as a New Drug Target. Trends Pharmacol Sci 2018; 39:560-572. [PMID: 29628275 DOI: 10.1016/j.tips.2018.03.004] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Revised: 03/13/2018] [Accepted: 03/14/2018] [Indexed: 12/19/2022]
Abstract
The first step in serotonin (5-HT) biosynthesis is catalyzed by tryptophan hydroxylase (TPH). There are two independent sources of the monoamine that have distinct functions: first, the TPH1-expressing enterochromaffin cells (ECs) of the gut; second, TPH2-expressing serotonergic neurons. TPH1-deficient mice revealed that peripheral 5-HT plays important roles in platelet function and in inflammatory and fibrotic diseases of gut, pancreas, lung, and liver. Therefore, TPH inhibitors were developed which cannot pass the blood-brain barrier to specifically block peripheral 5-HT synthesis. They showed therapeutic efficacy in several rodent disease models, and telotristat ethyl is the first TPH inhibitor to be approved for the treatment of carcinoid syndrome. We review this development and discuss further therapeutic options for these compounds.
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Affiliation(s)
- Susann Matthes
- Max-Delbrück Center for Molecular Medicine (MDC), Robert-Rössle-Straße 10, 13125 Berlin-Buch, Germany; University of Lübeck, Institute for Biology, Ratzeburger Allee 160, 23562 Lübeck, Germany
| | - Michael Bader
- Max-Delbrück Center for Molecular Medicine (MDC), Robert-Rössle-Straße 10, 13125 Berlin-Buch, Germany; University of Lübeck, Institute for Biology, Ratzeburger Allee 160, 23562 Lübeck, Germany; Berlin Institute of Health (BIH), Anna-Louisa-Karsch-Straße 2, 10178 Berlin, Germany; Charité University Medicine, Charitéplatz 1, 10117 Berlin, Germany; German Center for Cardiovascular Research (DZHK), Partner Site Berlin, Berlin, Germany.
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16
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Abstract
PURPOSE OF REVIEW To review recent advances and controversies in all aspects of carcinoid-syndrome. RECENT FINDINGS Over the last few years there have been a number of advances in all aspects of carcinoid syndrome as well as new therapies. These include new studies on its epidemiology which demonstrate it is increasing in frequency; increasing insights into the pathogenesis of its various clinical manifestations and into its natural history: definition of prognostic factors; new methods to verify its presence; the development of new drugs to treat its various manifestations, both initially and in somatostatin-refractory cases; and an increased understanding of the pathogenesis, natural history and management of carcinoid heart disease. These advances have generated several controversies and these are also reviewed. SUMMARY There have been numerous advances in all aspects of the carcinoid-syndrome, which is the most common functional syndrome neuroendocrine tumors produce. These advances are leading to new approaches to the management of these patients and in some cases to new controversies.
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Affiliation(s)
- Tetsuhide Ito
- Neuroendocrine Tumor Centre, Fukuoka Sanno Hospital, International University of Health and Welfare
| | - Lingaku Lee
- Department of Medicine and Bioregulatory Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
- Digestive Diseases Branch, NIDDK, NIH, Bethesda, Maryland, USA
| | - Robert T Jensen
- Digestive Diseases Branch, NIDDK, NIH, Bethesda, Maryland, USA
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17
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Khay K, Arous S, Bentaoune T, Drighil A, Habbal R. Carcinoid heart disease revealed by cyanosis with both right and left valvular involvement: a case report. J Med Case Rep 2018; 12:23. [PMID: 29386066 PMCID: PMC5791312 DOI: 10.1186/s13256-018-1574-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2017] [Accepted: 01/15/2018] [Indexed: 01/02/2023] Open
Abstract
Background Carcinoid heart disease is a frequent complication of carcinoid syndrome. It is related to the release by the carcinoid tumor and/or its metastases of bioactive substances such as serotonin. It is characterized by right-sided valvular involvement and can lead to right-sided heart failure. It is a prognostic factor of carcinoid syndrome. Case presentation We report the case of a 53-year-old African woman with an endocrine tumor of her small intestine complicated by carcinoid heart disease, revealed by right-sided heart failure. The diagnosis was confirmed by transthoracic echocardiography, which showed a severe tricuspid regurgitation with a patent foramen ovale, and by increased serum chromogranin A and urinary 5-hydroxyindoleacetic acid. Initially she was treated with medical therapy (furosemide and injection of somatostatin). Afterwards she was proposed for surgery. The evolution of her treatment was good. Conclusions Carcinoid syndrome is complicated in 60% of the cases of a heart disease, and is responsible for an important morbidity and mortality. The prognosis of patients with carcinoid heart disease has improved in recent years through somatostatin analogues and the cardiac surgery.
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Affiliation(s)
- Khadija Khay
- Department of Cardiology, Ibn Rushd University Hospital, Casablanca, Morocco
| | - Salim Arous
- Department of Cardiology, Ibn Rushd University Hospital, Casablanca, Morocco.
| | - Tarik Bentaoune
- Department of Cardiology, Ibn Rushd University Hospital, Casablanca, Morocco
| | - Abdenasser Drighil
- Department of Cardiology, Ibn Rushd University Hospital, Casablanca, Morocco
| | - Rachida Habbal
- Department of Cardiology, Ibn Rushd University Hospital, Casablanca, Morocco
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18
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Abstract
PURPOSE OF REVIEW Neuroendocrine tumors (NETs) were initially identified as a separate entity in the early 1900s as a unique malignancy that secretes bioactive amines. GI-NETs are the most frequent type and represent a unique subset of NETs, because at least 75% of these tumors represent gastrin stimulation of the enterochromaffin-like cell located in the body of the stomach. The purpose of this review is to understand the specific role of gastrin in the generation of Gastric NETs (G-NETs). RECENT FINDINGS We review here the origin of enterochromaffin cells gut and the role of hypergastrinemia in gastric enteroendocrine tumorigenesis. We describe generation of the first genetically engineered mouse model of gastrin-driven G-NETs that mimics the human phenotype. The common mechanism observed in both the hypergastrinemic mouse model and human carcinoids is translocation of the cyclin-dependent inhibitor p27kip to the cytoplasm and its subsequent degradation by the proteasome. Therapies that block degradation of p27kip, the CCKBR2 gastrin receptor, or gastrin peptide are likely to facilitate treatment.
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Affiliation(s)
- Sinju Sundaresan
- Division of Gastroenterology, Department of Internal Medicine, University of Michigan, BSRB, 2051, 109 Zina Pitcher PL, Ann Arbor, MI, 48109-2200, USA
| | - Anthony J Kang
- Division of Gastroenterology, Department of Internal Medicine, University of Michigan, BSRB, 2051, 109 Zina Pitcher PL, Ann Arbor, MI, 48109-2200, USA
| | - Juanita L Merchant
- Division of Gastroenterology, Department of Internal Medicine, University of Michigan, BSRB, 2051, 109 Zina Pitcher PL, Ann Arbor, MI, 48109-2200, USA.
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA.
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19
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Riechelmann RP, Pereira AA, Rego JFM, Costa FP. Refractory carcinoid syndrome: a review of treatment options. Ther Adv Med Oncol 2017; 9:127-137. [PMID: 28203303 PMCID: PMC5298401 DOI: 10.1177/1758834016675803] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Carcinoid syndrome (CSy) is a constellation of symptoms that may commonly present in patients with well differentiated neuroendocrine tumors (NETs), with somatostatin analogs (SSAs) being the first-line option for symptom management. However, symptomatic progression eventually occurs and in this scenario of a refractory CSy; several treatment options have been studied such as dose escalation of SSA, interferon and liver-directed therapies. Nevertheless, recent phase III trials have contributed to the understanding and management of this condition. We performed a comprehensive review of interventional studies examining refractory CSy to provide the evidence for current treatment options and propose a treatment sequence.
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Affiliation(s)
- Rachel P. Riechelmann
- Instituto do Câncer do Estado de São Paulo,Universidade de São Paulo, Ave. Dr Arnaldo, 251, São Paulo, SP – Brazil
| | - Allan A. Pereira
- Department of Radiology and Oncology, Instituto do Câncer do Estado de São Paulo, São Paulo, Brazil
| | - Juliana F. M. Rego
- Hospital Universitário Onofre Lopes, Universidade Federal do Rio Grande do Norte, Natal, Brazil
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20
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Lamarca A, Barriuso J, McNamara MG, Hubner RA, Valle JW. Telotristat ethyl: a new option for the management of carcinoid syndrome. Expert Opin Pharmacother 2016; 17:2487-2498. [PMID: 27817224 DOI: 10.1080/14656566.2016.1254191] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
INTRODUCTION Many patients with neuroendocrine tumour-related carcinoid syndrome treated with somatostatin analogues (SSA) won't achieve adequate symptom relief with the SSA alone; new treatment options are required. Telotristat ethyl is a tryptophan hydroxylase inhibitor, developed for the treatment of carcinoid syndrome. Areas covered: This review summarises the evidence supporting the role of telotristat ethyl in the management of carcinoid syndrome. Rationale, pharmacodynamics, pharmacokinetics, metabolism, clinical experience, efficacy and toxicity profiles are covered. Expert opinion: The efficacy of telotristat ethyl in producing a statistically-significant and clinically-meaningful reduction in daily bowel movements has been confirmed in phase III clinical trials. Two pivotal trials, TELESTAR and TELECAST, explored the role of telotristat ethyl in the management of patients with carcinoid syndrome refractory to SSAs focusing on patients with ≥4 and <4 daily bowel movements, respectively. In addition, benefit was confirmed in patient-reported outcomes. Based on activity and safe toxicity profile, telotristat ethyl is pending regulatory agencies evaluation and is likely to add to the armamentarium used to treat carcinoid syndrome. Long-term safety and efficacy data will be available from the ongoing TELEPATH study. The impact on carcinoid heart disease, mesenteric fibrosis and other long-term complications of carcinoid syndrome as well as its role earlier in patients' pathways remain investigational.
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Affiliation(s)
- Angela Lamarca
- a Department of Medical Oncology , The Christie NHS Foundation Trust , Manchester , UK
| | - Jorge Barriuso
- a Department of Medical Oncology , The Christie NHS Foundation Trust , Manchester , UK.,b Faculty of Medical, Biological and Human Sciences , University of Manchester , Manchester , UK
| | - Mairéad G McNamara
- a Department of Medical Oncology , The Christie NHS Foundation Trust , Manchester , UK.,c Institute of Cancer Sciences , University of Manchester , Manchester , UK
| | - Richard A Hubner
- a Department of Medical Oncology , The Christie NHS Foundation Trust , Manchester , UK
| | - Juan W Valle
- a Department of Medical Oncology , The Christie NHS Foundation Trust , Manchester , UK.,c Institute of Cancer Sciences , University of Manchester , Manchester , UK
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21
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Ito T, Lee L, Jensen RT. Treatment of symptomatic neuroendocrine tumor syndromes: recent advances and controversies. Expert Opin Pharmacother 2016; 17:2191-2205. [PMID: 27635672 DOI: 10.1080/14656566.2016.1236916] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
INTRODUCTION Neuroendocrine tumors(NETs), once thought rare, are increasing in frequency in most countries and receiving increasing-attention. NETs present two-treatment problems. A proportion is aggressive and a proportion has a functional, hormone-excess-state(F-NET), each of which must be treated. Recently, there have been many advances, well-covered in reviews/consensus papers on imaging-NETs; new, novel anti-tumor treatments and understanding their pathogenesis. However, little attention has been paid to advances in the treatment of the hormone-excess-state. These advances are usually reported in case-series, and case-reports with few large studies. In this paper these advances are reviewed. Areas covered: Advances in the last 5-years are concentrated on, but a review of literature from the last 10-years was performed. PubMed and other databases (Cochrane, etc.) were searched for F-NET-syndromes including carcinoid-syndrome, as well as meeting-abstracts on NETs. All advances that controlled hormone-excess-states or facilitated-control were covered. These include new medical-therapies [serotonin-synthesis inhibitors(telotristat), Pasireotide, new agents for treating ACTHomas], increased dosing with conventional therapies (octreotide-LAR, Lanreotide-Autogel), mTor inhibitors(everolimus), Tyrosine-kinase inhibitors(sunitinib),cytoreductive surgery, liver-directed therapies (embolization, chemoembolization, radioembolization, RFA), peptide radio-receptor-therapy(PRRT) and 131I-MIBG, ablation of primary F-NETs. Expert opinion: Although many of the newer therapies controlling the hormone-excess-states in F-NETs are reported in relatively few patients, all the approaches show promise. Their description also generates some controversies/unresolved areas,such as the order of these new treatments, their longterm-efficacy, and effectiveness of combinations which may require large,controlled studies.
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Affiliation(s)
- Tetsuhide Ito
- a Department of Medicine and Bioregulatory Science, Graduate School of Medical Sciences , Kyushu University , Fukuoka , Japan
| | - Lingaku Lee
- a Department of Medicine and Bioregulatory Science, Graduate School of Medical Sciences , Kyushu University , Fukuoka , Japan
| | - Robert T Jensen
- b Digestive Diseases Branch , NIDDK, NIH , Bethesda , MD , USA
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