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Pituitary Feb 2021Guidelines and consensus statements ensure that physicians managing acromegaly patients have access to current information on evidence-based treatments to optimize... (Review)
Review
Guidelines and consensus statements ensure that physicians managing acromegaly patients have access to current information on evidence-based treatments to optimize outcomes. Given significant novel recent advances in understanding acromegaly natural history and individualized therapies, the Pituitary Society invited acromegaly experts to critically review the current literature in the context of Endocrine Society guidelines and Acromegaly Consensus Group statements. This update focuses on how recent key advances affect treatment decision-making and outcomes, and also highlights the likely role of recently FDA-approved therapies as well as novel combination therapies within the treatment armamentarium.
Topics: Acromegaly; Animals; Female; Human Growth Hormone; Humans; Insulin-Like Growth Factor I; Male; Octreotide; Pituitary Neoplasms; Receptors, Somatostatin
PubMed: 33079318
DOI: 10.1007/s11102-020-01091-7 -
Cancer Science Jun 2022Theranostics is a term coined by combining the words "therapeutics" and "diagnostics," referring to single chemical entities developed to deliver therapy and diagnosis... (Review)
Review
Theranostics is a term coined by combining the words "therapeutics" and "diagnostics," referring to single chemical entities developed to deliver therapy and diagnosis simultaneously. Neuroendocrine tumors are rare cancers that occur in various organs of the body, and they express neuroendocrine factors such as chromogranin A and somatostatin receptor. Somatostatin analogs bind to somatostatin receptor, and when combined with diagnostic radionuclides, such as gamma-emitters, are utilized for diagnosis of neuroendocrine tumor. Somatostatin receptor scintigraphy when combined with therapeutic radionuclides, such as beta-emitters, are effective in treating neuroendocrine tumor as peptide receptor radionuclide therapy. Somatostatin receptor scintigraphy and peptide receptor radionuclide therapy are some of the most frequently used and successful theranostics for neuroendocrine tumor. In Japan, radiopharmaceuticals are regulated under a complex law system, creating a significant drug lag, which is a major public concern. It took nearly 10 years to obtain the approval for somatostatin receptor scintigraphy and peptide receptor radionuclide therapy use by the Japanese government. In 2021, Lu-DOTATATE (Lutathera), a drug for peptide receptor radionuclide therapy, was covered by insurance in Japan. In this review, we summarize the history of the development of neuroendocrine tumor theranostics and theranostics in general, as therapeutic treatment for cancer in the future. Furthermore, we briefly address the Japanese point of view regarding the development of new radiopharmaceuticals.
Topics: Humans; Neuroendocrine Tumors; Positron-Emission Tomography; Precision Medicine; Radioisotopes; Radionuclide Imaging; Radiopharmaceuticals; Receptors, Somatostatin
PubMed: 35271754
DOI: 10.1111/cas.15327 -
The Journal of Clinical Endocrinology... Jan 2022Currently, the first-generation somatostatin receptor ligands (fg-SRLs), octreotide LAR and lanreotide autogel, are the mainstays of acromegaly treatment and achieve... (Review)
Review
Currently, the first-generation somatostatin receptor ligands (fg-SRLs), octreotide LAR and lanreotide autogel, are the mainstays of acromegaly treatment and achieve biochemical control in approximately 40% of patients and tumor shrinkage in over 60% of patients. Pasireotide, a second-generation SRL, shows higher efficacy with respect to both biochemical control and tumor shrinkage but has a worse safety profile. In this review, we discuss the future perspectives of currently available SRLs, focusing on the use of biomarkers of response and precision medicine, new formulations of these SRLs and new drugs, which are under development. Precision medicine, which is based on biomarkers of response to treatment, will help guide the decision-making process by allowing physicians to choose the appropriate drug for each patient and improving response rates. New formulations of available SRLs, such as oral, subcutaneous depot, and nasal octreotide, may improve patients' adherence to treatment and quality of life since there will be more options available that better suit each patient. Finally, new drugs, such as paltusotine, somatropin, ONO-5788, and ONO-ST-468, may improve treatment adherence and present higher efficacy than currently available drugs.
Topics: Acromegaly; Antineoplastic Agents, Hormonal; Biomarkers, Tumor; Growth Hormone-Secreting Pituitary Adenoma; Humans; Octreotide; Peptides, Cyclic; Precision Medicine; Quality of Life; Randomized Controlled Trials as Topic; Receptors, Somatostatin; Somatostatin; Treatment Outcome
PubMed: 34618894
DOI: 10.1210/clinem/dgab726 -
Current Treatment Options in Oncology May 2022Neuroendocrine neoplasms (NEN) are a heterogeneous group of tumours derived from cells of neuroendocrine origin and can potentially arise everywhere in the human body.... (Review)
Review
Neuroendocrine neoplasms (NEN) are a heterogeneous group of tumours derived from cells of neuroendocrine origin and can potentially arise everywhere in the human body. The diagnostic assessment of NEN can be performed using a variety of PET radiopharmaceuticals. Well-differentiated NEN (NET) present a high expression of SSTR (somatostatin receptors) and can therefore be studied with 68Ga-DOTA-peptides ([68Ga]Ga-DOTANOC, [68Ga]Ga-DOTATOC, [68Ga]Ga-DOTATATE). Current guidelines recommend the use of SSTR imaging to assess disease extension at staging/restaging, follow-up, assessment of response to therapy and selection of patients who may benefit from radionuclide therapy (PRRT). [18F]F-FDG is used for the assessment of high-grade tumours (high-grade G2, G3 and NEC) and in every case, there is one or more mismatched lesions between diagnostic CT (positive) and SSTR-PET/CT (negative). [18F]F-DOPA is currently used for the assessment of medullary thyroid carcinoma, neuroblastoma, primary pheochromocytoma and abdominal paraganglioma. In recent years, however, several new tracers were designed exploiting the many potential targets of the neuroendocrine cell and were employed in clinical trials for both imaging and therapy. Currently, the real-life clinical impact of these tracers is still mostly not known; however, the favourable biodistribution (e.g. [68Ga]Ga-FAPI, SSTR antagonists) and the possibility to use new theranostic pairs may provide novel diagnostic as well as therapeutic options (e.g. [68Ga]Ga-PSMA, [64Cu]Cu-SARTATE, [68Ga]Ga-CXCR4) for NEN patients.
Topics: Copper Radioisotopes; Humans; Neuroendocrine Tumors; Positron Emission Tomography Computed Tomography; Positron-Emission Tomography; Radionuclide Imaging; Radiopharmaceuticals; Receptors, Somatostatin; Tissue Distribution
PubMed: 35325412
DOI: 10.1007/s11864-022-00967-z -
Frontiers in Endocrinology 2022Molecular therapeutic targets in growth hormone (GH)-secreting adenomas range from well-characterized surface receptors that recognize approved drugs, to surface and... (Review)
Review
Molecular therapeutic targets in growth hormone (GH)-secreting adenomas range from well-characterized surface receptors that recognize approved drugs, to surface and intracellular markers that are potential candidates for new drug development. Currently available medical therapies for patients with acromegaly bind to somatostatin receptors, GH receptor, or dopamine receptors, and lead to attainment of disease control in most patients. The degree of control is variable: however, correlates with both disease aggressiveness and tumor factors that predict treatment response including somatostatin receptor subtype expression, granulation pattern, kinases and their receptors, and other markers of proliferation. A better understanding of the mechanisms underlying these molecular markers and their relationship to outcomes holds promise for expanding treatment options as well as a more personalized approach to treating patients with acromegaly.
Topics: Humans; Acromegaly; Adenoma; Receptors, Somatostatin; Growth Hormone-Secreting Pituitary Adenoma; Pituitary Neoplasms
PubMed: 36545335
DOI: 10.3389/fendo.2022.1068061 -
International Journal of Molecular... Jun 2019In recent decades, the incidence of neuroendocrine tumors (NETs) has steadily increased. Due to the slow-growing nature of these tumors and the lack of early symptoms,... (Review)
Review
In recent decades, the incidence of neuroendocrine tumors (NETs) has steadily increased. Due to the slow-growing nature of these tumors and the lack of early symptoms, most cases are diagnosed at advanced stages, when curative treatment options are no longer available. Prognosis and survival of patients with NETs are determined by the location of the primary lesion, biochemical functional status, differentiation, initial staging, and response to treatment. Somatostatin analogue (SSA) therapy has been a mainstay of antisecretory therapy in functioning neuroendocrine tumors, which cause various clinical symptoms depending on hormonal hypersecretion. Beyond symptomatic management, recent research demonstrates that SSAs exert antiproliferative effects and inhibit tumor growth via the somatostatin receptor 2 (SSTR2). Both the PROMID (placebo-controlled, prospective, randomized study in patients with metastatic neuroendocrine midgut tumors) and the CLARINET (controlled study of lanreotide antiproliferative response in neuroendocrine tumors) trial showed a statistically significant prolongation of time to progression/progression-free survival (TTP/PFS) upon SSA treatment, compared to placebo. Moreover, the combination of SSA with peptide receptor radionuclide therapy (PRRT) in small intestinal NETs has proven efficacy in the phase 3 neuroendocrine tumours therapy (NETTER 1) trial. PRRT is currently being tested for enteropancreatic NETs versus everolimus in the COMPETE trial, and the potential of SSTR-antagonists in PRRT is now being evaluated in early phase I/II clinical trials. This review provides a synopsis on the pharmacological development of SSAs and their use as antisecretory drugs. Moreover, this review highlights the clinical evidence of SSAs in monotherapy, and in combination with other treatment modalities, as applied to the antiproliferative management of neuroendocrine tumors with special attention to recent high-quality phase III trials.
Topics: Animals; Antineoplastic Agents, Hormonal; Clinical Trials as Topic; Disease-Free Survival; Humans; Neuroendocrine Tumors; Octreotide; Peptides, Cyclic; Receptors, Somatostatin; Signal Transduction; Somatostatin
PubMed: 31234481
DOI: 10.3390/ijms20123049 -
Journal of Nuclear Medicine : Official... Sep 2022Peptide receptor radiotherapy with somatostatin analogs has been successfully used for years as a treatment for somatostatin-overexpressing tumors. Treatment of...
Peptide receptor radiotherapy with somatostatin analogs has been successfully used for years as a treatment for somatostatin-overexpressing tumors. Treatment of neuroendocrine tumors (NETs) with the β-particle emitter Lu-DOTATATE is currently considered the standard of care for subjects with gastroenteropancreatic NETs. Despite the success of Lu-DOTATATE, there remains significant room for improvement in terms of both safety and efficacy. Targeted α-emitter therapy with isotopes such as Pb has the potential to improve both. Here, we present the preliminary results of the phase 1 first-in-humans dose-escalation trial evaluating Pb-DOTAMTATE (a bifunctional metal chelator [DOTAM] and the SSTR-targeting peptide [TATE]) in patients with somatostatin receptor-positive NETs. Twenty subjects with histologically confirmed NETs, prior positive somatostatin analog scans, and no prior history of Lu/Y/In peptide receptor radiotherapy, with different primary sites of the disease, were enrolled. Treatment began with single ascending doses of Pb-DOTAMTATE, with subsequent cohorts receiving an incremental 30% dose increase, which was continued until a tumor response or a dose-limiting toxicity was observed. This was followed by a multiple ascending dose regimen. The recommended phase 2 dose regimen consisted of 4 cycles of 2.50 MBq/kg (67.6 μCi/kg) of Pb-DOTAMTATE administered at 8-wk intervals, intravenously. Ten subjects received the highest dose, 2.50 MBq/kg/cycle (67.6 μCi/kg/cycle). Treatment was well tolerated, with the most common treatment-emergent adverse events being nausea, fatigue, and alopecia. No serious treatment-emergent adverse events were related to the study drug, and no subjects required treatment delay or a dose reduction. An objective radiologic response of 80% was observed for the first 10 subjects treated at the recommended phase 2 dose. Targeted α-therapy with Pb-DOTAMTATE has been shown to be well tolerated. Preliminary efficacy results are highly promising. If these results are confirmed in a larger, multicenter clinical trial, Pb-DOTAMTATE would provide a substantial benefit over currently Food and Drug Administration-approved therapies for patients with metastatic or inoperable SSTR-expressing NETs regardless of the grade and location of the primary tumor.
Topics: Chelating Agents; Humans; Lead; Lead Radioisotopes; Neuroendocrine Tumors; Octreotide; Organometallic Compounds; Positron-Emission Tomography; Radionuclide Imaging; Radiopharmaceuticals; Receptors, Somatostatin; Somatostatin
PubMed: 34992153
DOI: 10.2967/jnumed.121.263230 -
Journal of Nuclear Medicine : Official... Sep 2017The molecular imaging and treatment of neuroendocrine tumors (NETs) with radiolabeled somatostatin analogs represent a milestone in the development of theranostic... (Review)
Review
The molecular imaging and treatment of neuroendocrine tumors (NETs) with radiolabeled somatostatin analogs represent a milestone in the development of theranostic compounds. Whole-body scintigraphy with In-pentetreotide has revolutionized the diagnosis and staging of NETs and the evaluation of treatment outcomes. At present, diagnostic accuracy with positron-emitting radionuclides is greater than 90%. Peptide receptor radionuclide therapy (PRRT) has become a well-accepted treatment for patients with well-differentiated inoperable or metastatic NETs and disease progression after first-line treatment. Disease control rates (complete or partial remission or stable disease in patients with formerly progressive disease) of up to 95%, with a low incidence of long-term hematologic and renal toxicity, have been reported. In a recently published randomized trial, compared with intensified treatment of midgut NETs with long-acting and repeatable octreotide, PRRT reduced the hazard of disease progression and death by 79%. Upcoming developments in PRRT include the use of somatostatin receptor antagonists and α-emitting radionuclides, which may further enhance treatment outcomes.
Topics: Animals; Diagnostic Imaging; Drug Discovery; Humans; Molecular Targeted Therapy; Receptors, Somatostatin; Safety
PubMed: 28864613
DOI: 10.2967/jnumed.117.191015 -
The Journal of Clinical Endocrinology... Sep 2023Pheochromocytomas and paragangliomas (PPGLs) with pathogenic mutations in the succinate dehydrogenase subunit B (SDHB) are associated with a high metastatic risk....
CONTEXT
Pheochromocytomas and paragangliomas (PPGLs) with pathogenic mutations in the succinate dehydrogenase subunit B (SDHB) are associated with a high metastatic risk. Somatostatin receptor 2 (SSTR2)-dependent imaging is the most sensitive imaging modality for SDHB-related PPGLs, suggesting that SSTR2 expression is a significant cell surface therapeutic biomarker of such tumors.
OBJECTIVE
Exploration of the relationship between SSTR2 immunoreactivity and SDHB immunoreactivity, mutational status, and clinical behavior of PPGLs. Evaluation of SSTR-based therapies in metastatic PPGLs.
METHODS
Retrospective analysis of a multicenter cohort of PPGLs at 6 specialized Endocrine Tumor Centers in Germany, The Netherlands, and Switzerland. Patients with PPGLs participating in the ENSAT registry were included. Clinical data were extracted from medical records, and immunohistochemistry (IHC) for SDHB and SSTR2 was performed in patients with available tumor tissue. Immunoreactivity of SSTR2 was investigated using Volante scores. The main outcome measure was the association of SSTR2 IHC positivity with genetic and clinical-pathological features of PPGLs.
RESULTS
Of 202 patients with PPGLs, 50% were SSTR2 positive. SSTR2 positivity was significantly associated with SDHB- and SDHx-related PPGLs, with the strongest SSTR2 staining intensity in SDHB-related PPGLs (P = .01). Moreover, SSTR2 expression was significantly associated with metastatic disease independent of SDHB/SDHx mutation status (P < .001). In metastatic PPGLs, the disease control rate with first-line SSTR-based radionuclide therapy was 67% (n = 22, n = 11 SDHx), and with first-line "cold" somatostatin analogs 100% (n = 6, n = 3 SDHx).
CONCLUSION
SSTR2 expression was independently associated with SDHB/SDHx mutations and metastatic disease. We confirm a high disease control rate of somatostatin receptor-based therapies in metastatic PPGLs.
Topics: Humans; Adrenal Gland Neoplasms; Neoplasms, Second Primary; Paraganglioma; Pheochromocytoma; Receptors, Somatostatin; Retrospective Studies; Succinate Dehydrogenase
PubMed: 36946182
DOI: 10.1210/clinem/dgad166 -
Annals of Oncology : Official Journal... Aug 2015Pulmonary carcinoids (PCs) are rare tumors. As there is a paucity of randomized studies, this expert consensus document represents an initiative by the European... (Review)
Review
Pulmonary neuroendocrine (carcinoid) tumors: European Neuroendocrine Tumor Society expert consensus and recommendations for best practice for typical and atypical pulmonary carcinoids.
BACKGROUND
Pulmonary carcinoids (PCs) are rare tumors. As there is a paucity of randomized studies, this expert consensus document represents an initiative by the European Neuroendocrine Tumor Society to provide guidance on their management.
PATIENTS AND METHODS
Bibliographical searches were carried out in PubMed for the terms 'pulmonary neuroendocrine tumors', 'bronchial neuroendocrine tumors', 'bronchial carcinoid tumors', 'pulmonary carcinoid', 'pulmonary typical/atypical carcinoid', and 'pulmonary carcinoid and diagnosis/treatment/epidemiology/prognosis'. A systematic review of the relevant literature was carried out, followed by expert review.
RESULTS
PCs are well-differentiated neuroendocrine tumors and include low- and intermediate-grade malignant tumors, i.e. typical (TC) and atypical carcinoid (AC), respectively. Contrast CT scan is the diagnostic gold standard for PCs, but pathology examination is mandatory for their correct classification. Somatostatin receptor imaging may visualize nearly 80% of the primary tumors and is most sensitive for metastatic disease. Plasma chromogranin A can be increased in PCs. Surgery is the treatment of choice for PCs with the aim of removing the tumor and preserving as much lung tissue as possible. Resection of metastases should be considered whenever possible with curative intent. Somatostatin analogs are the first-line treatment of carcinoid syndrome and may be considered as first-line systemic antiproliferative treatment in unresectable PCs, particularly of low-grade TC and AC. Locoregional or radiotargeted therapies should be considered for metastatic disease. Systemic chemotherapy is used for progressive PCs, although cytotoxic regimens have demonstrated limited effects with etoposide and platinum combination the most commonly used, however, temozolomide has shown most clinical benefit.
CONCLUSIONS
PCs are complex tumors which require a multidisciplinary approach and long-term follow-up.
Topics: Antineoplastic Combined Chemotherapy Protocols; Bronchoscopy; Carboplatin; Carcinoid Heart Disease; Carcinoid Tumor; Cisplatin; Dacarbazine; Etoposide; Europe; Humans; Lung Neoplasms; Pneumonectomy; Positron-Emission Tomography; Receptors, Somatostatin; Societies, Medical; Temozolomide; Tomography, X-Ray Computed; Ultrasonography
PubMed: 25646366
DOI: 10.1093/annonc/mdv041