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The programme of the German Congress for Laboratory Medicine 2022 was essentially designed by the divisions of the German Society for Clinical Chemistry and Laboratory Medicine (DGKL). Almost all chairpersons of the divisions organised a 90-min symposium on current topics, i.e. conceptualised the symposia and invited speakers. For this article all chairpersons summarised the lectures that were given within the symposia. The DGKL’s work is structured into 5 areas of expertise: Molecular Diagnostics, Learning & Teaching, Quality & Management, Laboratory & Diagnostics and Biobanks & Informatics. The areas of expertise are in turn subdivided into divisions. About the history of the establishment of this new structure within the DGKL you can find information in the editorial of this issue.

Programmed cell death, accidental cell degradation and active extrusion constantly lead to the release of DNA fragments into human body fluids from virtually all cell and tissue types. It is widely accepted that these cell-free DNA (cfDNA) molecules retain the cell-type specific genetic and epigenetic features. Particularly, cfDNA in plasma or serum has been utilized for molecular diagnostics. The current clinically implemented liquid biopsy approaches are mostly based on detecting genetic differences in cfDNA molecules from healthy and diseased cells. Their diagnostic potential is limited to pathologies involving genetic alterations, by the low proportion of cfDNA molecules carrying the mutation(s) relative to the total cfDNA pool, and by the detection limit of employed techniques. Recently, research efforts turned to epigenetic features of cfDNA molecules and found that the tissue-of-origin of individual cfDNA molecules can be inferred from epigenetic characteristics. Analysis of, e.g., methylation patterns, nucleosome or transcription factor binding site occupancies, fragment size distribution or fragment end motifs, and histone modifications determined the cell or tissue-of-origin of individual cfDNA molecules. With this tissue-of origin-analysis, it is possible to estimate the contributions of different tissues to the total cfDNA pool in body fluids and find tissues with increased cell death (pathologic condition), expanding the portfolio of liquid biopsies beyond genetics and towards a wide range of pathologies, such as autoimmune disorders, cardiovascular diseases, and inflammation, among many others. In this review, we give an overview on the status of tissue-of-origin approaches and focus on what is needed to exploit the full potential of liquid biopsies towards minimally invasive screening methods with broad clinical applications.

Genomes of diverse origins are continuously shed into human body fluids in the form of fragmented cell-free DNA (cfDNA). These molecules maintain the genetic and epigenetic codes of their originating source, and often carry additional layers of unique information in newly discovered physico-chemical features. Characterization of cfDNA thus presents the opportunity to non-invasively reconstruct major parts of the host- and metagenome in silico. Data from a single specimen can be leveraged to detect a broad range of disease-specific signatures and has already enabled the development of many pioneering diagnostic tests. Moreover, data from serial sampling may allow unparalleled mapping of the scantily explored landscape of temporal genomic changes as it relates to various changes in different physiological and pathological states of individuals. In this review, we explore how this vast dimension of biological information accessible through cfDNA analysis is being tapped towards the development of increasingly powerful molecular assays and how it is shaping emerging technologies. We also discuss how this departure from traditional paradigms of snapshot genetic testing may pave the way for an onrush of new and exciting discoveries in human biology.

Early detection is crucial for optimal treatment and prognosis of cancer. New approaches for pan-cancer screening comprise the comprehensive characterization of circulating tumor DNA (ctDNA) in plasma by next generation sequencing and molecular profiling of mutations and methylation patterns, as well as fragmentation analysis. These promise the accurate detection and localization of multiple cancers in early disease stages. However, studies with real screening populations have to show their clinical utility and practicability.

Legal regulations and guidelines such as the Guidelines of the German Medical Association for the Quality Assurance of Laboratory Medical Examinations (Rili-BAEK) and ISO 15189 apply to electronic laboratory reports. However, many laboratories struggle with practical implementation of these regulations and guidelines.

Point-of-care antigen tests (PoC-AgTs) for the rapid detection of SARS-CoV-2 infection enable screening of additional populations with less effort, independent of laboratories and at a low cost. PoC-AgTs have therefore been included in national testing strategies with additional quality requirements to address limitations in specificity and sensitivity. Information given in the package inserts of the test providers should enable the user to evaluate the performance of a PoC-AgT in advance. The quality of this information has been independently assessed since the Corona Test Ordinance came into force in Germany in October 2020.

Abstract Background Selective Internal Radiation Therapy (SIRT) is a new and effective locoregional anticancer therapy for colorectal cancer patients with liver metastases. Markers for prediction of therapy response and prognosis are needed for the individual management of those patients undergoing SIRT. Methods Blood samples were prospectively and consecutively taken from 49 colorectal cancer patients with extensive hepatic metastases before, three, six, 24 and 48 h after SIRT to analyze the concentrations of nucleosomes and further laboratory parameters, and to compare them with the response to therapy regularly determined 3 months after therapy and with overall survival. Results Circulating nucleosomes, cytokeratin-19 fragments (CYFRA 21-1), carcinoembryonic antigen (CEA), C-reactive protein (CRP) and various liver markers increased already 24 h after SIRT. Pretherapeutical levels of CYFRA 21-1, CEA, cancer antigen 19-9 (CA 19-9), asparate-aminotransferase (AST) and lactate dehydrogenase (LDH) as well as 24 h values of nucleosomes were significantly higher in patients suffering from disease progression (N = 35) than in non-progressive patients (N = 14). Concerning overall survival, CEA, CA 19-9, CYFRA 21-1, CRP, LDH, AST, choline esterase (CHE), gamma-glutamyl-transferase, alkaline phosphatase, and amylase (all 0 h, 24 h) and nucleosomes (24 h) were found to be prognostic relevant markers in univariate analyses. In multivariate Cox-Regression analysis, the best prognostic model was obtained for the combination of CRP and AST. When 24 h values were additionally included, nucleosomes (24 h) further improved the existing model. Conclusion Panels of biochemical markers are helpful to stratify pretherapeutically colorectal cancer patients for SIR-therapy and to early estimate the response to SIR-therapy.

Abstract Background Transarterial chemoembolization (TACE) therapy is an effective locoregional treatment in hepatocellular cancer (HCC) patients. For early modification of therapy, markers predicting therapy response are urgently required. Methods Here, sera of 50 prospectively and consecutively included HCC patients undergoing 71 TACE therapies were taken before and 3 h, 6 h and 24 h after TACE application to analyze concentrations of circulating nucleosomes, cytokeratin-19 fragments (CYFRA 21-1), alpha fetoprotein (AFP), C-reactive protein (CRP) and several liver biomarkers, and to compare these with radiological response to therapy. Results While nucleosomes, CYFRA 21-1, CRP and some liver biomarkers increased already 24 h after TACE, percental changes of nucleosome concentrations before and 24 h after TACE and pre- and posttherapeutic values of AFP, gamma-glutamyl-transferase (GGT) and alkaline phosphatase (AP) significantly indicated the later therapy response (39 progression versus 32 no progression). In multivariate analysis, nucleosomes (24 h), AP (24 h) and TACE number were independent predictive markers. The risk score of this combination model achieved an AUC of 81.8% in receiver operating characteristic (ROC) curves and a sensitivity for prediction of non-response to therapy of 41% at 97% specificity, and of 72% at 78% specificity. Conclusion Circulating nucleosomes and liver markers are valuable tools for early estimation of the efficacy of TACE therapy in HCC patients.

Abstract Background Elevated levels of nucleosomal DNA fragments can be detected in plasma and sera of patients with malignant diseases. Methods We investigated the course of nucleosomal DNA, thymidine kinase, lactate dehydrogenase and leukocytes in sera of 25 patients with acute myeloid leukemia during the first cycle of induction chemotherapy and tested their power to distinguish between patients with complete remission and those with no remission. Results Almost all patients showed strongly decreasing levels of nucleosomal DNA during the first week, in some cases after initial peaks. In overall analysis of variance, DNA levels could clearly distinguish between patients with complete remission, who had higher DNA values, and those with insufficient response (p = 0.017). The area under the curve of DNA values of days 2–4 after start of therapy (AUC 2–4) discriminated between both groups with a sensitivity of 56% at a specificity of 100%. Further, pretherapeutic levels and AUC 2–4 of nucleosomal DNA correlated significantly with blast reduction after 16 days. A tendency to higher levels in patients with complete response was also found for thymidine kinase, lactate dehydrogenase and leukocytes, however the difference did not reach the level of significance (p = 0.542, p = 0.260, and p = 0.144, respectively). Conclusion Our results indicate that nucleosomal DNA fragments are valuable markers for the early prediction of therapeutic efficacy in patients with acute myeloid leukemia.