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result(s) for
"Schmelz, Hans"
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Misuse of tumor marker levels leads to an insufficient International Germ Cell Consensus Classification (IGCCCG) risk group assignment and impaired treatment
by
Seidel, Christoph
,
Schmelz, Hans‐Ulrich
,
Albers, Peter
in
Biomarkers
,
Biomarkers, Tumor
,
Cancer therapies
2023
Background Metastatic germ cell tumors of the testis (GCTs) are risk‐stratified according to the International Germ Cell Cancer Collaborative Group (IGCCCG) classification system. This risk classification is based on anatomical risk factors as well as tumor marker levels of AFP, HCG, and LDH assessed pre‐chemotherapy after orchiectomy treatment. An incorrect classification is possible when pre‐orchiectomy marker levels are used, possibly resulting in over‐ or undertreatment of patients. The aim was to investigate the potential frequency and clinical relevance of incorrect risk stratification using pre‐orchiectomy tumor marker levels. Methods A multicenter registry analysis, including patients with metastasized nonseminomatous GCT (NSGCT), was conducted by investigators of the German Testicular Cancer Study Group (GTCSG). Based on the marker levels at different timepoints, IGCCCG risk groups were calculated. The agreement was tested using Cohen's kappa. Results A total of 672 of 1910 (35%) patients were diagnosed with metastatic NSGCTs, and 523 (78%) had sufficient data for 224 follow‐up data points. By using pre‐orchiectomy tumor marker levels, 106 patients (20%) would have been incorrectly classified. Seventy‐two patients (14%) were classified into a higher risk category, and 34 patients (7%) were classified into a lower risk category. Cohen's kappa was 0.69 (p < 0.001), showing a strong agreement between the use of both marker timepoints. The treatment of misclassified patients would have resulted in an overtreatment of 72 patients or undertreatment of 34 patients. Conclusions The use of pre‐orchiectomy tumor marker levels may lead to an incorrect risk classification and might subsequently lead to under‐ or overtreatment of patients.
Journal Article
Diagnostic accuracy of third-generation dual-source dual-energy CT: a prospective trial and protocol for clinical implementation
by
Nestler, Tim
,
Ruf, Christian
,
Netsch, Christopher
in
Accuracy
,
Calcification (ectopic)
,
Computed tomography
2019
PurposeUric acid (UA) calculi can be referred to chemolitholysis rather than invasive treatment. Dual-energy computed tomography (DECT) may be able to distinguish between UA and non-UA (NUA) calculi. The aim of this study was to evaluate the validity of third-generation DECT for the first time and to investigate whether combining DECT with clinical parameters can increase its predictive accuracy.Materials and methodsAll patients who presented to our emergency department between January 2015 and March 2017 with urinary stones were prospectively included in this observational study and underwent DECT with subsequent interventional stone removal. Stone composition was analyzed using infrared spectrometry as the gold standard. Predictive accuracy of DECT and clinical covariates was computed by assessing univariate and multivariate areas under the curve (AUCs).ResultsOf 84 patients with 144 urinary stones, 10 (11.9%) patients had UA stones according to infrared spectrometry, and the remaining stones were NUA or mixed stones. DECT had a positive predictive value of 100% and a negative predictive value of 98.5% for UA stones. The AUC for urine pH alone was 0.71 and 0.97 for DECT plus urine pH. No UA stones were found in patients with a urine pH above > 5.5. Mean DLP was 225.15 ± 128.60 mGy*cm and mean effective dose was 3.38 ± 1.93 mSv.ConclusionsDECT is a safe method for assigning patients to oral chemolitholysis. Clinical preselection of patients based on urinary pH (< 6.0) leads to a more liable use of DECT. Third-generation DECT needs significant lower radiation doses compared to previous generations.
Journal Article
Thromboprophylaxis and the route of administration of chemotherapy in testicular cancer patients in German-speaking countries
2018
PurposeDue to the excellent cure rates for testicular cancer (TC), focus has shifted towards decreasing therapy-related morbidities. Thrombosis is a frequent complication of cisplatin chemotherapy. Furthermore, the optimal route of administration for chemotherapy is still under debate. The purpose of this study was to assess the patterns of care concerning dosing and duration of thromboprophylaxis currently utilized in TC patients in German-speaking countries as well as the route of chemotherapy administration.MethodsA standardized questionnaire was sent to all members of the German TC Study Group (GTCSG) and to all the urological university hospitals in Germany. The questionnaire was also sent to the oncologic clinics at those universities where urologists do not administer chemotherapy.ResultsThe response rate was 87% (55/63). Prophylactic anticoagulation with low-molecular-weight heparin (LMWH) was administered in 94% of the clinics. The dosing of LMWH was prophylactic (85%), high prophylactic (adjusted to bodyweight) (7%), or risk adapted (9%). After completion of chemotherapy, anticoagulation was continued in 15 clinics (33%) for 2 to 24 weeks, while the remainder stopped the LMWH upon cessation of chemotherapy. Chemotherapy was administered via central venous access in 59%, peripheral IV in 27%, or both in 14% of the clinics.ConclusionsMost of the institutions performed some form of thromboprophylaxis, although the modes of application varied by institution type and amongst the urologists and oncologists. Prospective studies are needed to evaluate the incidence, date of occurrence, and risk factors of venous thrombosis during TC chemotherapy to provide a recommendation concerning prophylactic anticoagulation.
Journal Article
Clinically Apparent and Occult Metastasized Seminoma: Almost Indistinguishable on the Transcriptional Level
2014
The aim of the present study was to examine the biological differences between seminomas with occult and clinically apparent metastases at the time of diagnosis of the primary tumor to gain insight into the biology of these tumors and facilitate the identification of novel predictors of seminoma metastasis.
Total RNA including small RNAs was isolated from testicular tumors of patients with pure seminoma presenting with lymphogenic metastasis (n = 5, clinical stage IIb/c) and occult metastasis (n = 5, clinical stage I). The regulation of biological processes was examined (1) throughout the mRNA transcriptome (whole genome microarrays, 8×60 K Array, Agilent with 4 samples/group) and (2) the miRNA transcriptome employing small RNA next generation sequencing (SOLID, Life Technologies with 5 samples/group). Protein coding genes (mRNAs) and small RNAs showing a significant (≥2-fold) difference between the groups were identified. Finally (3), we examined 95 candidate miRNAs in 36 apparent metastasized and another 5 occult metastasized seminoma using logistic regression analysis.
Among 19,596 genes, on average 12,894 mRNAs appeared expressed (65.8%, SD+/-2.4; range, 62.0-69.3%) and 16.99×106/13.94×106 small RNA reads were identified for apparent/occult metastasized seminoma. These reads on average convert into 9,901/9,675 small RNAs including 422/404 mature microRNAs. None of these mRNAs/small RNAs met our selection criteria for candidate genes. From 95 candidate miRNAs 44 appeared expressed, with 3 of them showing weak but significant (p = 0.05) differences among both groups.
Occult and apparent metastasized seminomas are biologically almost indistinguishable and probably represent no separate tumor entities. These findings may simplify future research on seminoma metastasis.
Journal Article
Small RNAs in the peripheral blood discriminate metastasized from non-metastasized seminoma
2014
Background
We aimed to better discriminate metastasized (lymphogen/occult/both combined) from non-metastasized seminoma based on post-transcriptional changes examined in the peripheral blood.
Methods
Total RNAs including small RNAs were isolated from the peripheral blood of patients suffering from metastasized testicular tumours (lymphogen, n = 5, clinical stage IIb/c; occult, n = 5, clinical stage I) and non-metastasized patients (n = 5, clinical stage I). Small RNA next generation sequencing (SOLID, Life Technologies) was employed to examine post-transcriptional changes. We searched for small RNAs showing at least 50 reads and a significant ≥ 2-fold difference using peripheral blood small RNAs of non-metastasized tumours as the reference group. Candidate small RNAs were examined in univariate logistic regression analysis and combinations of two small RNAs were further examined using support vector machines.
Results
On average 1.3x10
7
, 1.2x10
7
and 1.2x10
7
small RNA reads were detectable in non-metastasized, lymphogen and occult metastasized seminoma, respectively of which 73-76% remained after trimming. From these between 80-82% represented annotated reads and 7.2-7.8% (1.6-1.7x10
4
) were annotated small RNA tags. Of them 137 small RNAs showed > 50 reads and a ≥ two-fold difference to the reference. In univariate analysis we detected 33-35 different small RNAs which significantly discriminated lymphogen/occult/combined metastasized from non-metastasized seminoma and among these different comparisons it were the same small RNAs in 44-79%. Many combinations of two of these small RNAs completely discriminated metastasized from non-metastasized seminoma irrespective of the metastasis subtype.
Conclusions
Metastasized (either lymphogen or occult) seminoma can be completely discriminated from non-metastasized seminoma with a combination of two small RNAs measured in the peripheral blood.
Journal Article
German second-opinion network for testicular cancer: Sealing the leaky pipe between evidence and clinical practice
by
SCHRADER, ANDRES JAN
,
SCHRADER, MARK
,
DIECKMANN, KLAUS-PETER
in
Care and treatment
,
Classification
,
Clinical medicine
2014
In 2006, the German Testicular Cancer Study Group initiated an extensive evidence-based national second-opinion network to improve the care of testicular cancer patients. The primary aims were to reflect the current state of testicular cancer treatment in Germany and to analyze the project's effect on the quality of care delivered to testicular cancer patients. A freely available internet-based platform was developed for the exchange of data between the urologists seeking advice and the 31 second-opinion givers. After providing all data relevant to the primary treatment decision, urologists received a second opinion on their therapy plan within <48 h. Endpoints were congruence between the first and second opinion, conformity of applied therapy with the corresponding recommendation and progression-free survival rate of the introduced patients. Significance was determined by two-sided Pearson's χ2 test. A total of 1,284 second-opinion requests were submitted from November 2006 to October 2011, and 926 of these cases were eligible for further analysis. A discrepancy was found between first and second opinion in 39.5% of the cases. Discrepant second opinions led to less extensive treatment in 28.1% and to more extensive treatment in 15.6%. Patients treated within the framework of the second-opinion project had an overall 2-year progression-free survival rate of 90.4%. Approximately every 6th second opinion led to a relevant change in therapy. Despite the lack of financial incentives, data from every 8th testicular cancer patient in Germany were submitted to second-opinion centers. Second-opinion centers can help to improve the implementation of evidence into clinical practice.
Journal Article
Urology during Afghanistan mission: lessons learned and implications for the future
2023
PurposeBattle-related trauma is common in modern warfare and can lead to genitourinary injuries. In Western countries, urogenital injuries are rare in the civilian environment. The main objective of this study was to assess urological workload for surgeons on deployment.Material and methodsData were acquired over a period of five years of deployment in a U.S. facility in Afghanistan.ResultsGerman urological surgeons treated on average one urologic outpatient per day and performed 314 surgical interventions overall. Surgical interventions were categorized as battle-related interventions (BRIs, n = 169, 53.8%) and nonbattle-related interventions (non-BRIs, n = 145, 46.2%). In the BRI group, interventions were mainly performed on the external genitalia (n = 67, 39.6%), while in the non-BRI group, endourological procedures predominated (n = 109). This is consistent with a higher rate of abdominal or pelvic procedures performed in the BRI group (n = 51, 30.2%).Furthermore, the types of interventions performed on the external genitalia differed significantly. In the BRI group, 58.2% (n = 39) of interventions were scrotal explorations, but none of those procedures were performed in the non-BRI group (p < 0.001). However, 50.0% (n = 13) of scrotal explorations in the non-BRI group were due to suspected torsions of the testes followed by orchidopexy (BRI: n = 1, 1.5%, p < 0.001). Concerning outpatients, the consultation was mainly due to complaints concerning the external genitalia (32.7%, n = 252) or kidney/ureteral stones (23.5%, n = 181).ConclusionWhile the treatment of urological outpatients in a deployment setting resembles the treatment of soldiers in Germany, BRIs requires abdominal/retroperitoneal urosurgical skills and basic skills in reconstructive surgery.
Journal Article
Radiomics-driven spectral profiling of six kidney stone types with monoenergetic CT reconstructions in photon-counting CT
2025
Objectives
Urolithiasis, a common and painful urological condition, is influenced by factors such as lifestyle, genetics, and medication. Differentiating between different types of kidney stones is crucial for personalized therapy. The purpose of this study is to investigate the use of photon-counting computed tomography (PCCT) in combination with radiomics and machine learning to develop a method for automated and detailed characterization of kidney stones. This approach aims to enhance the accuracy and detail of stone classification beyond what is achievable with conventional computed tomography (CT) and dual-energy CT (DECT).
Materials and methods
In this ex vivo study, 135 kidney stones were first classified using infrared spectroscopy. All stones were then scanned in a PCCT embedded in a phantom. Various monoenergetic reconstructions were generated, and radiomics features were extracted. Statistical analysis was performed using Random Forest (RF) classifiers for both individual reconstructions and a combined model.
Results
The combined model, using radiomics features from all monoenergetic reconstructions, significantly outperformed individual reconstructions and SPP parameters, with an AUC of 0.95 and test accuracy of 0.81 for differentiating all six stone types. Feature importance analysis identified key parameters, including NGTDM_Strength and wavelet-LLH_firstorder_Variance.
Conclusion
This ex vivo study demonstrates that radiomics-driven PCCT analysis can improve differentiation between kidney stone subtypes. The combined model outperformed individual monoenergetic levels, highlighting the potential of spectral profiling in PCCT to optimize treatment through image-based strategies.
Key Points
Question
How can photon-counting computed tomography (PCCT) combined with radiomics improve the differentiation of kidney stone types beyond conventional CT and dual-energy CT, enhancing personalized therapy?
Findings
Our ex vivo study demonstrates that a combined spectral-driven radiomics model achieved 95% AUC and 81% test accuracy in differentiating six kidney stone types.
Clinical relevance
Implementing PCCT-based spectral-driven radiomics allows for precise non-invasive differentiation of kidney stone types, leading to improved diagnostic accuracy and more personalized, effective treatment strategies, potentially reducing the need for invasive procedures and recurrence.
Graphical Abstract
Journal Article
German specialists treating testicular cancer follow different guidelines with resulting inconsistency in assessment of retroperitoneal lymph-node metastasis: clinical implications and possible corrective measures
2023
BackgroundTesticular germ cell tumors (GCTs) are aggressive but highly curable tumors. To avoid over/undertreatment, reliable clinical staging of retroperitoneal lymph-node metastasis is necessary. Current clinical guidelines, in their different versions, lack specific recommendations on how to measure lymph-node metastasis.ObjectiveWe aimed to assess the practice patterns of German institutions frequently treating testicular cancer for measuring retroperitoneal lymph-node size.MethodsAn 8‐item survey was distributed among German university hospitals and members of the German Testicular Cancer Study Group.ResultsIn the group of urologists, 54.7% assessed retroperitoneal lymph nodes depending on their short-axis diameter (SAD) (33.3% in any plane, 21.4% in the axial plane), while 45.3% used long-axis diameter (LAD) for the assessment (42.9% in any plane, 2.4% in the axial plane). Moreover, the oncologists mainly assessed lymph-node size based on the SAD (71.4%). Specifically, 42.9% of oncologists assessed the SAD in any plane, while 28.5% measured this dimension in the axial plane. Only 28.6% of oncologists considered the LAD (14.3% in any plane, 14.3% in the axial plane). None of the oncologists and 11.9% of the urologists (n = 5) always performed an MRI for the initial assessment, while for follow-up imaging, the use increased to 36.5% of oncologists and 31% of urologists. Furthermore, only 17% of the urologists, and no oncologists, calculated lymph-node volume in their assessment (p = 0.224).ConclusionClear and consistent measurement instructions are urgently needed to be present in all guidelines across different specialistic fields involved in testicular cancer management.
Journal Article
Comparison of automated kidney stone size measurement and volumetry in photon counting CT compared to 3rd generation dual energy CT and physically measurements – an ex vivo study
by
Faby, Sebastian
,
Hesse, Albrecht
,
Overhoff, Daniel
in
Computed tomography
,
Humans
,
Kidney Calculi - chemistry
2024
Purpose
This ex vivo study aimed to compare a newly developed dual-source photon-counting CT (PCCT) with a 3rd generation dual-source dual-energy CT (DECT) for the detection and measurement (stone lengths and volumetrics) of urinary stones.
Methods
143 urinary stones with a known geometry were physically measured and defined as reference values. Next, urinary stones were placed in an anthropomorphic abdomen-model and were scanned with DECT and PCCT. Images were read by two experienced examiners and automatically evaluated using a specific software.
Results
DECT and PCCT showed a high sensitivity for manual stone detection of 97.9% and 94.4%, and for automatic detection of 93.0% and 87.4%, respectively. Compared to that uric acid and xanthine stones were recognized slightly worse by DECT and PCCT with manual stone detection (93.3% and 82.2%), and with automatic detection (77.8% and 60.0%). All other stone entities were completely recognized. By comparing the maximum diameter of the reference value and DECT, Pearson-correlation was 0.96 (
p
< 0.001) for manual and 0.97 (
p
< 0.001) for automatic measurement, and for PCCT it was 0.94 (
p
< 0.001) for manual and 0.97 (
p
< 0.001) for automatic measurements. DECT and PCCT can also reliably determine volume manually and automatically with a Pearson-correlation of 0.99 (
p
< 0.001), respectively.
Conclusion
Both CTs showed comparable results in stone detection, length measurement and volumetry compared to the reference values. Automatic measurement tends to underestimate the maximum diameter. DECT proved to be slightly superior in the recognition of xanthine and uric acid stones.
Journal Article