Claudia Helga Dorothee Le Guin

Dr. Claudia Helga Dorothee Le Guin

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Research Focus & Metrics

Academic Career Length

10Years (2017-Present)

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

Representative Publications

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18 February 2020 in Cancers
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Alda Maria Cunha RolaAlda Maria Cunha Rola
Alda Maria Cunha Rola
ATAzzam Taktak
Azzam Taktak
AEAntonio Eleuteri
Antonio Eleuteri
HKHelen Kalirai
Helen Kalirai
HHHeinrich Heimann
Heinrich Heimann
Sarah E. CouplandSarah E. Coupland
Sarah E. Coupland
Uveal melanoma (UM) is fatal in ~50% of patients as a result of disseminated disease. This study aims to externally validate the Liverpool Uveal Melanoma Prognosticator Online V3 (LUMPO3) to determine its reliability in predicting survival after treatment for choroidal melanoma when utilizing external data from other ocular oncology centers. Anonymized data of 1836 UM patients from seven international ocular oncology centers were analyzed with LUMPO3 to predict the 10-year survival for each patient in each external dataset. The analysts were masked to the patient outcomes. Model predictions were sent to an independent statistician to evaluate LUMPO3’s performance using discrimination and calibration methods. LUMPO3’s ability to discriminate between UM patients who died of metastatic UM and those who were still alive was fair-to-good, with C-statistics ranging from 0.64 to 0.85 at year 1. The pooled estimate for all external centers was 0.72 (95% confidence interval: 0.68 to 0.75). Agreement between observed and predicted survival probabilities was generally good given differences in case mix and survival rates between different centers. Despite the differences between the international cohorts of patients with primary UM, LUMPO3 is a valuable tool for predicting all-cause mortality in this disease when using data from external centers.

22 July 2019 in Cancers
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CGClaudia Helga Dorothee Le Guin
Claudia Helga Dorothee Le Guin
KMKlaus Alfred Metz
Klaus Alfred Metz
SKStefan Horst Kreis
Stefan Horst Kreis
NBNikolaos E. Bechrakis
Nikolaos E. Bechrakis
NBNorbert Bornfeld
Norbert Bornfeld
DLDietmar Lohmann
Dietmar Lohmann
Several tumors, including uveal melanoma, show somatic mutations of GNAQ/GNA11. Circumscribed choroidal hemangioma is a benign tumor that becomes symptomatic in adulthood. In some patients, morphologic examination of biopsies is required for differential diagnosis between amelanotic choroidal melanoma and circumscribed choroidal hemangioma. Here, we report the results of GNAQ/GNA11 mutation analysis in samples from circumscribed choroidal hemangioma. Deep amplicon sequencing (Illumina MiSeq, San Diego, CA, USA) of positions R183 and Q209 of GNAQ and GNA11 in tissue samples from 33 patients with histologically diagnosed circumscribed choroidal hemangioma. All patients underwent biopsy or enucleation at our clinic between 2008 and 2018. To enable detection of variant alleles at low fractions, read depth exceeded 15,000-fold. DNA for genetic analysis was prepared from either snap-frozen (n = 22) or FFPE (n = 11) tissue samples. Samples from 28/33 patients (85%) showed a somatic missense mutation of GNAQ (c.626 A > G) predicted to result in p.Q209R. Variant allele fraction was variable (range 2.3% to 28%). Variants of GNAQ resulting in p.Q209 are characteristic for circumscribed choroidal hemangiomas. It appears that the GNAQ mutation spectrum in this tumor is narrow, possibly restricted to p.Q209R. Moreover, the spectrum is distinct from that of uveal melanoma, in which alterations resulting in p.Q209R are very rare.

21 July 2021 in Cancer Medicine
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CGClaudia Helga Dorothee Le Guin
Claudia Helga Dorothee Le Guin
NBNorbert Bornfeld
Norbert Bornfeld
NBNikolaos E. Bechrakis
Nikolaos E. Bechrakis
LJLeyla Jabbarli
Leyla Jabbarli
HRHeike Richly
Heike Richly
MZMichael Zeschnigk
Michael Zeschnigk
Background: Eye salvaging therapy of malignant melanomas of the uvea can preserve the eye in most cases, but still about half of patients die from metastatic disease. Previous analyses of cell‐free DNA from plasma had shown detectable levels of tumor‐specific GNAQ/GNA11 mutations in patients with the clinical diagnosis of progressive disease. However, data on the time span that elapses from the detection of ctDNA in plasma to the clinical detection of metastases (diagnostic lead time) are missing.Methods: We examined 135 patients with uveal melanoma. Cell‐free DNA was isolated from a total of 807 blood samples which were taken over a period of up to 41 months and analyzed for the presence of GNAQ/GNA11 mutations by deep amplicon sequencing.Results: Twenty‐one of the 135 patients developed metastases or recurrence. A ctDNA signal was identified in the plasma of 17 of the 21 patients. In 10 patients, this ctDNA signal preceded the clinical diagnosis of metastasis by 2–10 months. In 10 other patients, a ctDNA signal was only detected in samples obtained shortly before or after radiotherapy. The presence of a ctDNA signal in 16 of the remaining 125 patients was linked to clinical manifestation of metastases (n = 14) or tumor recurrence (n = 2) with a sensitivity and specificity of 80% and 96%, respectively.Conclusion: Detection of ctDNA in plasma can provide a diagnostic lead time over the clinical diagnosis of metastases or tumor recurrence. Longer lead times are to be expected if intervals between sampling are shortened.

31 January 2020 in BMC Psychology
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MLMarietta Lieb
Marietta Lieb
STSefik Tagay
Sefik Tagay
ABAnja Breidenstein
Anja Breidenstein
THTobias Hepp
Tobias Hepp
CGClaudia Helga Dorothee Le Guin
Claudia Helga Dorothee Le Guin
YEYesim Erim
Yesim Erim
Background: The risk of metastases in uveal melanoma can accurately be estimated through genetic analysis of the tumor. A growing number of patients decide to receive information on their prognosis, although this can be extremely burdensome. Studies on the psychosocial impact of testing are sparse. The objective of this study was to examine traits of patients opting for prognostication, to investigate its psychosocial impact and the use of psycho-oncological services over time. We further examined characteristics of patients utilizing these services and risk factors of prolonged psychological distress.Design and methods: This study is a non-randomized controlled prospective clinical observational trial. Patients availing for prognostication formed the test group, while those who opted out constituted the observational group. The psychosocial impact of genetic testing was assessed with the following variables: resilience, social support, fear of tumor progression, depression, general distress, health-related quality of life, estimation of the perceived risk, and the utilization of psycho-oncological interventions. Data were assessed at five different time points over a period of 12 months. We applied binary logistic regression analysis, multiple linear regressions and a mixed model.Results: Of 175 patients, 63 decided to obtain prognostic information. Treatment method (enucleation > brachytherapy), lower social support and higher general distress could significantly predict patient’s choice for prognostic testing. After result announcement, perceived risk of metastases was significantly increased in patients with poor prognosis, while it decreased in those with good prognosis. Overall, a significant decrease over time appeared concerning fear of progression, general distress, depression and anxiety. Mental quality of life increased over time. The utilization of psycho-oncological interventions increased significantly after prognostication; however, this was equivalent in the test and observational groups. Female sex, higher general distress and higher anxiety predicted greater use of psycho-oncological interventions.Discussion: Availing of prognostic testing is not associated with poorer subsequent psychological well-being. It rather may help to alleviate distress and promote a more realistic risk perception. However, psychological support should be available to all patients, independent of prognosis and treatment, especially considering that patients with low social support and high distress increasingly opt for prognostication.

14 April 2021 in Cancers
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MRMadlen Reschke
Madlen Reschke
EBEva Biewald
Eva Biewald
LBLeo Bronstein
Leo Bronstein
IBInes B. Brecht
Ines B. Brecht
SDSabine Dittner-Moormann
Sabine Dittner-Moormann
PKPetra Ketteler
Petra Ketteler
Retinoblastoma and other eye tumors in childhood are rare diseases. Many eye tumors are the first signs of a genetic tumor predisposition syndrome and the affected children carry a higher risk of developing other cancers later in life. Clinical and genetic data of all children with eye tumors diagnosed between 2013–2018 in Germany and Austria were collected in a multicenter prospective observational study. In five years, 300 children were recruited into the study: 287 with retinoblastoma, 7 uveal melanoma, 3 ciliary body medulloepithelioma, 2 retinal astrocytoma, 1 meningioma of the optic nerve extending into the eye. Heritable retinoblastoma was diagnosed in 44% of children with retinoblastoma. One child with meningioma of the optic nerve extending into the eye was diagnosed with neurofibromatosis 2. No pathogenic constitutional variant in DICER1 was detected in a child with medulloepithelioma while two children did not receive genetic analysis. Because of the known association with tumor predisposition syndromes, genetic counseling should be offered to all children with eye tumors. Children with a genetic predisposition to cancer should receive a tailored surveillance including detailed history, physical examinations and, if indicated, imaging to screen for other cancer. Early detection of cancers may reduce mortality.

3 October 2023 in Investigative Ophthalmology & Visual Science
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VKViktoria Kim
Viktoria Kim
MGMaja Guberina
Maja Guberina
NBNikolaos E. Bechrakis
Nikolaos E. Bechrakis
DLDietmar R. Lohmann
Dietmar R. Lohmann
MZMichael Zeschnigk
Michael Zeschnigk
CGClaudia Helga Dorothee Le Guin
Claudia Helga Dorothee Le Guin
Purpose: Uveal melanoma (UM) is a tumor of the eye that metastasizes in approximately half of cases. Prognostic testing requires accessibility to tumor tissue, which is usually not available with eye-preserving therapies. Noninvasive approaches to prognostic testing that provide valuable information for patient care are therefore needed. The aim of this study was to evaluate the use of circulating cell-free plasma DNA analysis in UM patients undergoing brachytherapy. Methods: The study recruited 26 uveal melanoma patients referred to the department between February and October 2020. Blood samples were collected at various time points before, during, and after treatment, and deep amplicon sequencing was used to identify oncogenic variant alleles of the GNAQ and GNA11 genes, which serve as indicators for the presence of circulating tumor DNA (ctDNA). Results: The results showed that all patients were ctDNA negative before brachytherapy. In 31% of patients, ctDNA was detected during therapy. The variant allele fraction of GNAQ or GNA11 alleles in ctDNA positive samples ranged from 0.24% to 2% and correlates with the largest basal diameter and thickness of the tumor. Conclusions: The findings suggest that brachytherapy increases the presence of tumor DNA in the plasma of UM patients. Thus ctDNA analysis may offer a noninvasive approach for prognostic testing. However, efforts are still required to lower the limit of detection for tumor-specific genetic alterations.