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Boursier C, Zaragori T, Bros M, Bordonne M, Melki S, Taillandier L, Blonski M, Roch V, Marie PY, Karcher G, Imbert L, Verger A. Semi-automated segmentation methods of SSTR PET for dosimetry prediction in refractory meningioma patients treated by SSTR-targeted peptide receptor radionuclide therapy. Eur Radiol 2023; 33:7089-7098. [PMID: 37148355 DOI: 10.1007/s00330-023-09697-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 02/10/2023] [Accepted: 03/12/2023] [Indexed: 05/08/2023]
Abstract
OBJECTIVES Tumor dosimetry with somatostatin receptor-targeted peptide receptor radionuclide therapy (SSTR-targeted PRRT) by 177Lu-DOTATATE may contribute to improved treatment monitoring of refractory meningioma. Accurate dosimetry requires reliable and reproducible pretherapeutic PET tumor segmentation which is not currently available. This study aims to propose semi-automated segmentation methods to determine metabolic tumor volume with pretherapeutic 68Ga-DOTATOC PET and evaluate SUVmean-derived values as predictive factors for tumor-absorbed dose. METHODS Thirty-nine meningioma lesions from twenty patients were analyzed. The ground truth PET and SPECT volumes (VolGT-PET and VolGT-SPECT) were computed from manual segmentations by five experienced nuclear physicians. SUV-related indexes were extracted from VolGT-PET and the semi-automated PET volumes providing the best Dice index with VolGT-PET (Volopt) across several methods: SUV absolute-value (2.3)-threshold, adaptative methods (Jentzen, Otsu, Contrast-based method), advanced gradient-based technique, and multiple relative thresholds (% of tumor SUVmax, hypophysis SUVmean, and meninges SUVpeak) with optimal threshold optimized. Tumor-absorbed doses were obtained from the VolGT-SPECT, corrected for partial volume effect, performed on a 360° whole-body CZT-camera at 24, 96, and 168 h after administration of 177Lu-DOTATATE. RESULTS Volopt was obtained from 1.7-fold meninges SUVpeak (Dice index 0.85 ± 0.07). SUVmean and total lesion uptake (SUVmeanxlesion volume) showed better correlations with tumor-absorbed doses than SUVmax when determined with the VolGT (respective Pearson correlation coefficients of 0.78, 0.67, and 0.56) or Volopt (0.64, 0.66, and 0.56). CONCLUSION Accurate definition of pretherapeutic PET volumes is justified since SUVmean-derived values provide the best tumor-absorbed dose predictions in refractory meningioma patients treated by 177Lu-DOTATATE. This study provides a semi-automated segmentation method of pretherapeutic 68Ga-DOTATOC PET volumes to achieve good reproducibility between physicians. CLINICAL RELEVANCE STATEMENT SUVmean-derived values from pretherapeutic 68Ga-DOTATOC PET are predictive of tumor-absorbed doses in refractory meningiomas treated by 177Lu-DOTATATE, justifying to accurately define pretherapeutic PET volumes. This study provides a semi-automated segmentation of 68Ga-DOTATOC PET images easily applicable in routine. KEY POINTS • SUVmean-derived values from pretherapeutic 68Ga-DOTATOC PET images provide the best predictive factors of tumor-absorbed doses related to 177Lu-DOTATATE PRRT in refractory meningioma. • A 1.7-fold meninges SUVpeak segmentation method used to determine metabolic tumor volume on pretherapeutic 68Ga-DOTATOC PET images of refractory meningioma treated by 177Lu-DOTATATE is as efficient as the currently routine manual segmentation method and limits inter- and intra-observer variabilities. • This semi-automated method for segmentation of refractory meningioma is easily applicable to routine practice and transferrable across PET centers.
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Affiliation(s)
- Caroline Boursier
- Department of Nuclear Medicine, Université de Lorraine, CHRU Nancy, F-54000, Nancy, France.
- Université de Lorraine, IADI, INSERM U1254, F-54000, Nancy, France.
- Nancyclotep Imaging Platform, F-54000, Nancy, France.
| | | | - Marie Bros
- Department of Nuclear Medicine, Université de Lorraine, CHRU Nancy, F-54000, Nancy, France
| | - Manon Bordonne
- Department of Nuclear Medicine, Université de Lorraine, CHRU Nancy, F-54000, Nancy, France
| | - Saifeddine Melki
- Department of Nuclear Medicine, Université de Lorraine, CHRU Nancy, F-54000, Nancy, France
| | - Luc Taillandier
- Department of Neuro-Oncology, Université de Lorraine, CHRU Nancy, F-54000, Nancy, France
- Centre de Recherche en Automatique de Nancy CRAN, UMR 7039, Université de Lorraine, CNRS, F-54000, Nancy, France
| | - Marie Blonski
- Department of Neuro-Oncology, Université de Lorraine, CHRU Nancy, F-54000, Nancy, France
- Centre de Recherche en Automatique de Nancy CRAN, UMR 7039, Université de Lorraine, CNRS, F-54000, Nancy, France
| | - Veronique Roch
- Department of Nuclear Medicine, Université de Lorraine, CHRU Nancy, F-54000, Nancy, France
- Nancyclotep Imaging Platform, F-54000, Nancy, France
| | - Pierre-Yves Marie
- Department of Nuclear Medicine, Université de Lorraine, CHRU Nancy, F-54000, Nancy, France
- Université de Lorraine, IADI, INSERM U1254, F-54000, Nancy, France
- Nancyclotep Imaging Platform, F-54000, Nancy, France
| | - Gilles Karcher
- Department of Nuclear Medicine, Université de Lorraine, CHRU Nancy, F-54000, Nancy, France
- Nancyclotep Imaging Platform, F-54000, Nancy, France
| | - Laëtitia Imbert
- Department of Nuclear Medicine, Université de Lorraine, CHRU Nancy, F-54000, Nancy, France
- Université de Lorraine, IADI, INSERM U1254, F-54000, Nancy, France
- Nancyclotep Imaging Platform, F-54000, Nancy, France
| | - Antoine Verger
- Department of Nuclear Medicine, Université de Lorraine, CHRU Nancy, F-54000, Nancy, France
- Université de Lorraine, IADI, INSERM U1254, F-54000, Nancy, France
- Nancyclotep Imaging Platform, F-54000, Nancy, France
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Graillon T, Tabouret E, Salgues B, Horowitz T, Padovani L, Appay R, Farah K, Dufour H, Régis J, Guedj E, Barlier A, Chinot O. Innovative treatments for meningiomas. Rev Neurol (Paris) 2023; 179:449-463. [PMID: 36959063 DOI: 10.1016/j.neurol.2023.03.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 03/06/2023] [Accepted: 03/07/2023] [Indexed: 03/25/2023]
Abstract
Multi-recurrent high-grade meningiomas remain an unmet medical need in neuro-oncology when iterative surgeries and radiation therapy sessions fail to control tumor growth. Nevertheless, the last 10years have been marked by multiple advances in the comprehension of meningioma tumorigenesis via the discovery of new driver mutations, the identification of activated intracellular signaling pathways, and DNA methylation analyses, providing multiple potential therapeutic targets. Today, Anti-VEGF and mTOR inhibitors are the most used and probably the most active drugs in aggressive meningiomas. Peptide radioactive radiation therapy aims to target SSTR2A receptors, which are strongly expressed in meningiomas, but have an insufficient effect in most aggressive meningiomas, requiring the development of new techniques to increase the dose applied to the tumor. Based on the multiple potential intracellular targets, multiple targeted therapy clinical trials targeting Pi3K-Akt-mTOR and MAP kinase pathways as well as cell cycle and particularly, cyclin D4-6 are ongoing. Recently discovered driver mutations, SMO, Akt, and PI3KCA, offer new targets but are mostly observed in benign meningiomas, limiting their clinical relevance mainly to rare aggressive skull base meningiomas. Therefore, NF2 mutation remains the most frequent mutation and main challenging target in high-grade meningioma. Recently, inhibitors of focal adhesion kinase (FAK), which is involved in tumor cell adhesion, were tested in a phase 2 clinical trial with interesting but insufficient activity. The Hippo pathway was demonstrated to interact with NF2/Merlin and could be a promising target in NF2-mutated meningiomas with ongoing multiple preclinical studies and a phase 1 clinical trial. Recent advances in immune landscape comprehension led to the proposal of the use of immunotherapy in meningiomas. Except in rare cases of MSH2/6 mutation or high tumor mass burden, the activity of PD-1 inhibitors remains limited; however, its combination with various radiation therapy modalities is particularly promising. On the whole, therapeutic management of high-grade meningiomas is still challenging even with multiple promising therapeutic targets and innovations.
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Affiliation(s)
- T Graillon
- Aix-Marseille University, AP-HM, Inserm, MMG, Neurosurgery department, La Timone Hospital, Marseille, France.
| | - E Tabouret
- Aix-Marseille University, AP-HM, CNRS, INP, Inst Neurophysiopathol, CHU Timone, Service de Neurooncologie, Marseille, France
| | - B Salgues
- Nuclear Medicine Department, Groupe Hospitalier Pitié-Salpêtrière-Charles-Foix, Assistance publique-Hôpitaux de Paris, Sorbonne Université, Paris, France
| | - T Horowitz
- AP-HM, CNRS, centrale Marseille, Institut Fresnel, Timone Hospital, CERIMED, Nuclear Medicine Department, Aix-Marseille University, Marseille, France
| | - L Padovani
- AP-HM, Timone Hospital, Radiotherapy Department, Marseille, France
| | - R Appay
- AP-HM, CHU Timone, Service d'Anatomie Pathologique et de Neuropathologie, Marseille, France; Aix-Marseille University, CNRS, INP, Inst Neurophysiopathol, Marseille, France
| | - K Farah
- Aix-Marseille University, Institut de Neurosciences des Systèmes, UMR Inserm 1106, Functional Neurosurgery and Radiosurgery, Timone University Hospital, Marseille, France
| | - H Dufour
- Aix-Marseille University, AP-HM, Inserm, MMG, Neurosurgery department, La Timone Hospital, Marseille, France
| | - J Régis
- Aix-Marseille University, Institut de Neurosciences des Systèmes, UMR Inserm 1106, Functional Neurosurgery and Radiosurgery, Timone University Hospital, Marseille, France
| | - E Guedj
- AP-HM, CNRS, centrale Marseille, Institut Fresnel, Timone Hospital, CERIMED, Nuclear Medicine Department, Aix-Marseille University, Marseille, France
| | - A Barlier
- Aix-Marseille University, AP-HM, Inserm, MMG, Laboratory of Molecular Biology Hospital La Conception, Marseille, France
| | - O Chinot
- Aix-Marseille University, AP-HM, CNRS, INP, Inst Neurophysiopathol, CHU Timone, Service de Neurooncologie, Marseille, France
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Minczeles NS, Bos EM, de Leeuw RC, Kros JM, Konijnenberg MW, Bromberg JEC, de Herder WW, Dirven CMF, Hofland J, Brabander T. Efficacy and safety of peptide receptor radionuclide therapy with [ 177Lu]Lu-DOTA-TATE in 15 patients with progressive treatment-refractory meningioma. Eur J Nucl Med Mol Imaging 2023; 50:1195-1204. [PMID: 36454268 DOI: 10.1007/s00259-022-06044-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Accepted: 11/13/2022] [Indexed: 12/03/2022]
Abstract
PURPOSE There is no evidence-based systemic therapy for patients with progressive meningiomas for whom surgery or external radiotherapy is no longer an option. In this study, the efficacy and safety of peptide receptor radionuclide therapy (PRRT) in patients with progressive, treatment-refractory meningiomas were evaluated. METHODS Retrospective analysis of all meningioma patients treated with [177Lu]Lu-DOTA-TATE from 2000 to 2020 in our centre. Primary outcomes were response according to RANO bidimensional and volumetric criteria and progression-free survival (PFS). Overall survival (OS) and tumour growth rate (TGR) were secondary endpoints. TGR was calculated as the percentage change in surface or volume per month. RESULTS Fifteen meningioma patients received [177Lu]Lu-DOTA-TATE (7.5-29.6 GBq). Prior to PRRT, all patients had received external radiotherapy, and 14 patients had undergone surgery. All WHO grades were included WHO 1 (n=3), WHO 2 (n=5), and WHO 3 (n=6). After PRRT, stable disease was observed in six (40%) patients. The median PFS was 7.8 months with a 6-month PFS rate of 60%. The median OS was 13.6 months with a 12-month OS rate of 60%. All patients had progressive disease prior to PRRT, with an average TGR of 4.6% increase in surface and 14.8% increase in volume per month. After PRRT, TGR declined to 3.1% in surface (p=0.016) and 5.0% in volume (p=0.013) per month. CONCLUSION In this cohort of meningioma patients with exhaustion of surgical and radiotherapeutic options and progressive disease, it was shown that PRRT plays a role in controlling tumour growth.
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Affiliation(s)
- Noémie S Minczeles
- Department of Internal Medicine, Section of Endocrinology, ENETS Centre of Excellence Rotterdam, Erasmus MC and Erasmus MC Cancer Institute, Rotterdam, The Netherlands. .,Department of Radiology & Nuclear Medicine, ENETS Centre of Excellence Rotterdam, Erasmus MC, Rotterdam, The Netherlands.
| | - Eelke M Bos
- Department of Neurosurgery, Erasmus MC, Rotterdam, The Netherlands
| | - Reinoud C de Leeuw
- Department of Radiology & Nuclear Medicine, ENETS Centre of Excellence Rotterdam, Erasmus MC, Rotterdam, The Netherlands
| | - Johan M Kros
- Department of Pathology, ENETS Centre of Excellence Rotterdam, Erasmus MC, Rotterdam, The Netherlands
| | - Mark W Konijnenberg
- Department of Radiology & Nuclear Medicine, ENETS Centre of Excellence Rotterdam, Erasmus MC, Rotterdam, The Netherlands
| | | | - Wouter W de Herder
- Department of Internal Medicine, Section of Endocrinology, ENETS Centre of Excellence Rotterdam, Erasmus MC and Erasmus MC Cancer Institute, Rotterdam, The Netherlands
| | | | - Johannes Hofland
- Department of Internal Medicine, Section of Endocrinology, ENETS Centre of Excellence Rotterdam, Erasmus MC and Erasmus MC Cancer Institute, Rotterdam, The Netherlands
| | - Tessa Brabander
- Department of Radiology & Nuclear Medicine, ENETS Centre of Excellence Rotterdam, Erasmus MC, Rotterdam, The Netherlands
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Somatostatin Receptor Theranostics for Refractory Meningiomas. Curr Oncol 2022; 29:5550-5565. [PMID: 36005176 PMCID: PMC9406720 DOI: 10.3390/curroncol29080438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 07/31/2022] [Accepted: 08/01/2022] [Indexed: 11/17/2022] Open
Abstract
Somatostatin receptor (SSTR)-targeted peptide receptor radionuclide therapy (PRRT) represents a promising approach for treatment-refractory meningiomas progressing after surgery and radiotherapy. The aim of this study was to provide outcomes of patients harboring refractory meningiomas treated by 177Lu-DOTATATE and an overall analysis of progression-free survival at 6 months (PFS-6) of the same relevant studies in the literature. Eight patients with recurrent and progressive WHO grade II meningiomas were treated after multimodal pretreatment with 177Lu-DOTATATE between 2019 and 2022. Primary and secondarily endpoints were progression-free survival at 6-months (PFS-6) and toxicity, respectively. PFS-6 analysis of our case series was compared with other similar relevant studies that included 86 patients treated with either 177Lu-DOTATATE or 90Y-DOTATOC. Our retrospective study showed a PFS-6 of 85.7% for WHO grade II progressive refractory meningiomas. Treatment was clinically and biologically well tolerated. The overall analysis of the previous relevant studies showed a PFS-6 of 89.7% for WHO grade I meningiomas (n = 29); 57.1% for WHO grade II (n = 21); and 0 % for WHO grade III (n = 12). For all grades (n = 86), including unknown grades, PFS-6 was 58.1%. SSTR-targeted PRRT allowed us to achieve prolonged PFS-6 in patients with WHO grade I and II progressive refractory meningiomas, except the most aggressive WHO grade II tumors. Large scale randomized trials are warranted for the better integration of PRRT in the treatment of refractory meningioma into clinical practice guidelines.
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Zhang-Yin JT, Girard A, Bertaux M. What Does PET Imaging Bring to Neuro-Oncology in 2022? A Review. Cancers (Basel) 2022; 14:cancers14040879. [PMID: 35205625 PMCID: PMC8870476 DOI: 10.3390/cancers14040879] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 02/01/2022] [Accepted: 02/07/2022] [Indexed: 01/27/2023] Open
Abstract
Simple Summary Positron emission tomography (PET) imaging is increasingly used to supplement MRI in the management of patient with brain tumors. In this article, we provide a review of the current place and perspectives of PET imaging for the diagnosis and follow-up of from primary brain tumors such as gliomas, meningiomas and central nervous system lymphomas, as well as brain metastases. Different PET radiotracers targeting different biological processes are used to accurately depict these brain tumors and provide unique metabolic and biologic information. Radiolabeled amino acids such as [18F]FDOPA or [18F]FET are used for imaging of gliomas while both [18F]FDG and amino acids can be used for brain metastases. Meningiomas can be seen with a high contrast using radiolabeled ligands of somatostatin receptors, which they usually carry. Unconventional tracers that allow the study of other biological processes such as cell proliferation, hypoxia, or neo-angiogenesis are currently being studied for brain tumors imaging. Abstract PET imaging is being increasingly used to supplement MRI in the clinical management of brain tumors. The main radiotracers implemented in clinical practice include [18F]FDG, radiolabeled amino acids ([11C]MET, [18F]FDOPA, [18F]FET) and [68Ga]Ga-DOTA-SSTR, targeting glucose metabolism, L-amino-acid transport and somatostatin receptors expression, respectively. This review aims at addressing the current place and perspectives of brain PET imaging for patients who suffer from primary or secondary brain tumors, at diagnosis and during follow-up. A special focus is given to the following: radiolabeled amino acids PET imaging for tumor characterization and follow-up in gliomas; the role of amino acid PET and [18F]FDG PET for detecting brain metastases recurrence; [68Ga]Ga-DOTA-SSTR PET for guiding treatment in meningioma and particularly before targeted radiotherapy.
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Affiliation(s)
| | - Antoine Girard
- Department of Nuclear Medicine, Centre Eugène Marquis, Université Rennes 1, 35000 Rennes, France
| | - Marc Bertaux
- Department of Nuclear Medicine, Foch Hospital, 92150 Suresnes, France
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Graillon T, Tabouret E, Chinot O. Chemotherapy and targeted therapies for meningiomas: what is the evidence? Curr Opin Neurol 2021; 34:857-867. [PMID: 34629433 DOI: 10.1097/wco.0000000000001002] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
PURPOSE OF REVIEW Although most meningiomas are slow growing tumors mainly controlled by surgery with or without radiotherapy, aggressive meningiomas that fail these conventional treatments constitute a rare situation, a therapeutic challenge and an unmet need in neuro-oncology. RECENT FINDING Mutational landscape in recurrent high-grade meningiomas includes mainly NF2 mutation or 22q chromosomal deletion, whereas telomerase reverse transcriptase promoter, BAP-1 and CDK2NA mutations were also found in aggressive meningiomas. Pi3K-Akt-mTOR pathway is currently the most relevant intracellular signaling pathway target in meningiomas with preliminary clinical activity observed. Assessment of drug activity with progression free survival rate at 6 months is challenging in regard to meningioma growth rate heterogeneity, so that 3-dimensional growth rate before and during treatment could be considered in the future to selected new active drugs. SUMMARY Despite a low evidence level, some systemic therapies may be considered for patients with recurrent meningioma not amenable to further surgery or radiotherapy. In recurrent high-grade meningioma, everolimus-octreotide combination, bevacizumab, sunitinib and peptide receptor radionuclide therapy exhibit a signal of activity that may justify their clinical use. Despite a lack of clear signal of activity to date, immunotherapy may offer new perspectives in the treatment of these refractory tumors.
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Affiliation(s)
- Thomas Graillon
- Aix Marseille Univ, APHM, INSERM, MMG, UMR1251, La Timone Hospital, neurosurgery department Marseille, France
| | - Emeline Tabouret
- Aix-Marseille Univ, APHM, CNRS, INP, Inst Neurophysiopathol, La Timone Hospital, Neurooncology Department, Marseille, France
| | - Olivier Chinot
- Aix-Marseille Univ, APHM, CNRS, INP, Inst Neurophysiopathol, La Timone Hospital, Neurooncology Department, Marseille, France
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Moody TW, Lee L, Ramos-Alvarez I, Iordanskaia T, Mantey SA, Jensen RT. Bombesin Receptor Family Activation and CNS/Neural Tumors: Review of Evidence Supporting Possible Role for Novel Targeted Therapy. Front Endocrinol (Lausanne) 2021; 12:728088. [PMID: 34539578 PMCID: PMC8441013 DOI: 10.3389/fendo.2021.728088] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2021] [Accepted: 08/02/2021] [Indexed: 12/13/2022] Open
Abstract
G-protein-coupled receptors (GPCRs) are increasingly being considered as possible therapeutic targets in cancers. Activation of GPCR on tumors can have prominent growth effects, and GPCRs are frequently over-/ectopically expressed on tumors and thus can be used for targeted therapy. CNS/neural tumors are receiving increasing attention using this approach. Gliomas are the most frequent primary malignant brain/CNS tumor with glioblastoma having a 10-year survival <1%; neuroblastomas are the most common extracranial solid tumor in children with long-term survival<40%, and medulloblastomas are less common, but one subgroup has a 5-year survival <60%. Thus, there is an increased need for more effective treatments of these tumors. The Bombesin-receptor family (BnRs) is one of the GPCRs that are most frequently over/ectopically expressed by common tumors and is receiving particular attention as a possible therapeutic target in several tumors, particularly in prostate, breast, and lung cancer. We review in this paper evidence suggesting why a similar approach in some CNS/neural tumors (gliomas, neuroblastomas, medulloblastomas) should also be considered.
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Affiliation(s)
- Terry W. Moody
- Department of Health and Human Services, National Cancer Institute, Center for Cancer Training, Office of the Director, Bethesda, MD, United States
| | - Lingaku Lee
- Digestive Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, United States
- Department of Gastroenterology, National Hospital Organization Kyushu Cancer Center, Fukuoka, Japan
| | - Irene Ramos-Alvarez
- Digestive Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Tatiana Iordanskaia
- Digestive Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Samuel A. Mantey
- Digestive Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Robert T. Jensen
- Digestive Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, United States
- *Correspondence: Robert T. Jensen,
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