Martin Alexander Walter

Dr. Martin Alexander Walter


Research Focus & Metrics

Academic Career Length

25Years (2002-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 October 2016 in Thyroid®
Verified
Journal Article
Open access
DRDouglas S. Ross
Douglas S. Ross
HBHenry B. Burch
Henry B. Burch
DCDavid S. Cooper
David S. Cooper
MGM. Carol Greenlee
M. Carol Greenlee
PLPeter Laurberg
Peter Laurberg
Martin Alexander WalterMartin Alexander Walter
Martin Alexander Walter
Background: Thyrotoxicosis has multiple etiologies, manifestations, and potential therapies. Appropriate treatment requires an accurate diagnosis and is influenced by coexisting medical conditions and patient preference. This document describes evidence-based clinical guidelines for the management of thyrotoxicosis that would be useful to generalist and subspecialty physicians and others providing care for patients with this condition. Methods: The American Thyroid Association (ATA) previously cosponsored guidelines for the management of thyrotoxicosis that were published in 2011. Considerable new literature has been published since then, and the ATA felt updated evidence-based guidelines were needed. The association assembled a task force of expert clinicians who authored this report. They examined relevant literature using a systematic PubMed search supplemented with additional published materials. An evidence-based medicine approach that incorporated the knowledge and experience of the panel was used to update the 2011 text and recommendations. The strength of the recommendations and the quality of evidence supporting them were rated according to the approach recommended by the Grading of Recommendations, Assessment, Development, and Evaluation Group. Results: Clinical topics addressed include the initial evaluation and management of thyrotoxicosis; management of Graves' hyperthyroidism using radioactive iodine, antithyroid drugs, or surgery; management of toxic multinodular goiter or toxic adenoma using radioactive iodine or surgery; Graves' disease in children, adolescents, or pregnant patients; subclinical hyperthyroidism; hyperthyroidism in patients with Graves' orbitopathy; and management of other miscellaneous causes of thyrotoxicosis. New paradigms since publication of the 2011 guidelines are presented for the evaluation of the etiology of thyrotoxicosis, the management of Graves' hyperthyroidism with antithyroid drugs, the management of pregnant hyperthyroid patients, and the preparation of patients for thyroid surgery. The sections on less common causes of thyrotoxicosis have been expanded. Conclusions: One hundred twenty-four evidence-based recommendations were developed to aid in the care of patients with thyrotoxicosis and to share what the task force believes is current, rational, and optimal medical practice.

10 June 2011 in Journal of Clinical Oncology
Verified
Journal Article
Closed access
AIAnna Imhof
Anna Imhof
PBPhilippe Brunner
Philippe Brunner
NMNicolas Marincek
Nicolas Marincek
MBMatthias Briel
Matthias Briel
CSChristian Schindler
Christian Schindler
Martin Alexander WalterMartin Alexander Walter
Martin Alexander Walter
Purpose: To investigate response, survival, and safety profile of the somatostatin-based radiopeptide 90yttrium-labeled tetraazacyclododecane-tetraacetic acid modified Tyr-octreotide ([90Y-DOTA]-TOC) in neuroendocrine cancers. Patients and Methods: In a clinical phase II single-center open-label trial, patients with neuroendocrine cancers were treated with repeated cycles of [90Y-DOTA]-TOC. Each cycle consisted of a single intravenous injection of 3.7GBq/m2 body-surface [90Y-DOTA]-TOC. Additional cycles were withheld in case of tumor progression and/or permanent toxicity. Results: Overall, 1,109 patients received 2,472 cycles of [90Y-DOTA]-TOC (median, two; range, one to 10 cycles per patient). Of the 1,109 patients, 378 (34.1%) experienced morphologic response; 172 (15.5%), biochemical response; and 329 (29.7%), clinical response. During a median follow-up of 23 months, 491 patients (44.3%) died. Longer survival was correlated with each: morphologic (hazard ratio [HR], 0.46; 95% CI, 0.38 to 0.56; median survival, 44.7 v 18.3 months; P < .001), biochemical (HR, 0.75; 95% CI, 0.59 to 0.96; 35.3 v 25.7 months; P = .023), and clinical response (HR, 0.68; 95% CI, 0.56 to 0.82; 36.8 v 23.5 months; P < .001). Overall, 142 patients (12.8%) developed grade 3 to 4 transient hematologic toxicities, and 103 patients (9.2%) experienced grade 4 to 5 permanent renal toxicity. Multivariable regression revealed that tumoral uptake in the initial imaging study was predictive for overall survival (HR, 0.45; 95% CI, 0.29 to 0.69; P < .001), whereas the initial kidney uptake was predictive for severe renal toxicity (HR, 1.59; 95% CI, 1.17 to 2.17; P = .003). Conclusion: This study documents the long-term outcome of [90Y-DOTA]-TOC treatment in a large cohort. Response to [90Y-DOTA]-TOC is associated with longer survival. Somatostatin receptor imaging is predictive for both survival after [90Y-DOTA]-TOC treatment and occurrence of renal toxicity.

12 March 2014 in JAMA
Verified
Journal Article
Open access
PDF file
BKBenjamin Kasenda
Benjamin Kasenda
EEErik von Elm
Erik von Elm
JYJohn You
John You
ABAnette Blümle
Anette Blümle
YTYuki Tomonaga
Yuki Tomonaga
MBMatthias Briel
Matthias Briel
Conducting high-quality randomized clinical trials (RCTs) is challenging and resource-demanding. Trials are often not conducted as planned or are even prematurely discontinued, eg, for reasons of unexpected harm from the intervention, early superiority, futility, administrative problems, or poor recruitment of participants. Trial discontinuation poses ethical concerns, particularly if results remain unreported, and may represent a considerable waste of scarce research resources.1-3

4 March 2005 in European Journal of Nuclear Medicine and Molecular Imaging
Verified
Journal Article
Closed access
PDF file
Martin Alexander WalterMartin Alexander Walter
Martin Alexander Walter
RMRalph A. Melzer
Ralph A. Melzer
CSChristian Schindler
Christian Schindler
JMJan Müller-Brand
Jan Müller-Brand
ATAlan Tyndall
Alan Tyndall
ENEgbert U. Nitzsche
Egbert U. Nitzsche

1 September 2017 in JAMA Oncology
Verified
Journal Article
Open access
PDF file
BBBirke Bausch
Birke Bausch
Francesca SchiaviFrancesca Schiavi
Francesca Schiavi
YNYing Ni
Ying Ni
JWJenny Welander
Jenny Welander
APAttila Patocs
Attila Patocs
FGfor the European-American-Asian Pheochromocytoma-Paraganglioma Registry Study Group
for the European-American-Asian Pheochromocytoma-Paraganglioma Registry Study Group
Preventive medicine has been dramatically improved by cancer genetics. The identification of susceptibility genes for hereditary forms of cancers in the past decades opened avenues for detection of second primary and recurrent tumors. Once a given germline mutation is detected, newly identified carriers are clinically investigated, and thus the diagnosis of tumors in an asymptomatic stage in the relatives of carriers becomes possible. Pheochromocytoma, paraganglioma, and associated inherited diseases served in this direction as important pacesetters. The susceptibility genes—including RET as causing multiple endocrine neoplasia type 2 (RefSeq NM_020975.4); VHL for von Hippel-Lindau disease (RefSeq NM_000551.3); SDHD, SDHC, and SDHB (succinate dehydrogenase subunits D [RefSeq NM_003002.3], C [RefSeq NM_003001.3], and B [RefSeq NM_003000.2]) for paraganglioma syndromes types 1, 3, and 4; and NF1 for neurofibromatosis type 1 (RefSeq NM_000267.3), herein summarized as classic susceptibility genes—have served as effective molecular tools for preventive medicine studies and practice in this field in the first years of the new millenium.1-8 These studies led to the end of the 10% rule for the frequency of hereditary pheochromocytoma and instead pointed to at least a 24% hereditary fraction.6,9 By 2010 and 2011, additional susceptibility genes for pheochromocytomas and paragangliomas were reported, including SDHA (succinate dehydrogenase subunit A [RefSeq NM_004168.3]), TMEM127 (transmembrane protein 127 [RefSeq NM_017849.3]), MAX (Myc-associated factor X [RefSeq NM_002382.4]), and SDHAF2 (succinate dehydrogenase complex assembly factor 2 [RefSeq NM_017841.2]).10-13 In contrast to the classic susceptibility genes, recommendations of the last International Symposium for Pheochromocytoma (2014) do not provide clinical management guidelines for those with mutations in the susceptibility genes analyzed and characterized herein.14 The main reasons are the limited number of sufficiently large registries, leading to limited clinical data associated with mutations of these genes. The much-needed and important process of returning to the clinical roots is a labor-intensive one. Thus, our comprehensive genetic and clinical characterization study intends to close the gap between finding a mutation in 1 of these 4 new susceptibility genes and the associated clinical data so that gene-informed risk assessment, counseling, and management can be performed.

10 November 2011 in European Journal of Nuclear Medicine and Molecular Imaging
Verified
Journal Article
Closed access
PDF file
MFMartin Fuchs
Martin Fuchs
MBMatthias Briel
Matthias Briel
TDThomas Daikeler
Thomas Daikeler
UWUlrich A. Walker
Ulrich A. Walker
HRHelmut Rasch
Helmut Rasch
Martin Alexander WalterMartin Alexander Walter
Martin Alexander Walter