Referenzbegutachtung als Instrument der Qualitätssicherung in der hämatopathologischen Diagnostik: Konkordanzraten am Universitätsklinikum Leipzig in den Jahren 2013-2018

Dem Fach Pathologie kommt eine zentrale Bedeutung in der Diagnostik und Therapie insbesondere maligner Erkrankungen zu, da die korrekte Diagnose eines Tumorleidens und des Stadiums der Tumorausbreitung die Grundlage für die weiterführende Therapie darstellt. Die Referenzbefundung ist ein Instrument, welches bei schwierigen oder seltenen Fällen eine spezialisierte histopathologische und molekularpathologische Diagnostik ermöglicht. Maligne Lymphome und myeloische Neoplasien gehören zu den am schwierigsten zu diagnostizierenden Tumorerkrankungen. Ziel der Arbeit war, alle hämatopathologischen Fälle aus der Routinediagnostik der Jahre 2013 – 2018 des Institutes für Pathologie, Universitätsklinikum Leipzig, welche zur referenzpathologischen Zweitbegutachtung versandt wurden, hinsichtlich der Diskordanzraten auszuwerten. Es sollte ein Vergleich der Primärdiagnose und der Referenzdiagnose sowie eine Auswertung hinsichtlich von konkordanten und diskordanten Diagnosen erfolgen.:Danksagung 1 Inhaltsverzeichnis 2 Abkürzungsverzeichnis 4 1. Einführung 6 1.1 Qualitätssicherung in der Pathologie 7 1.1.1 Präanalytik 7 1.1.2 Analytik 8 1.1.3 Postanalytik 8 1.1.4 Aspekte der Qualitätssicherung in der Hämatopathologie 9 1.2 Rationale für die pathologische Zweitbegutachtung 13 1.2.1 Lymphatische Neoplasien 13 1.2.2 Myeloische Neoplasien 16 2. Aufgabenstellung 18 3. Materialien und Methoden 19 4. Ergebnisse 24 4.1 Häufigkeiten 24 4.2 Fälle mit Primärdiagnose 25 4.2.1 B-Zell-Lymphome 25 4.2.2 T-Zell-Lymphome 34 4.2.3 Hodgkin-Lymphome 39 4.2.4 Myeloische Neoplasien 42 4.2.5 Reaktive Läsionen 45 4.2.6 Übrige Fälle 47 4.3 Fälle mit primär mehreren Differentialdiagnosen 49 4.3.1 B-Zell-Lymphome 49 4.3.2 T-Zell-Lymphome 51 4.3.3 Hodgkin-Lymphome 52 4.3.4 Myeloische Neoplasien 53 4.3.5 Reaktive Läsionen 53 4.3.6 Übrige Fälle 53 4.4 Zusammenfassende Auswertung 54 5. Diskussion 65 5.1 Literaturrecherche, Diskordanzraten 65 5.2 B-Zell-Lymphome 68 5.3 T-Zell-Lymphome 74 5.4 Hodgkin-Lymphome 77 5.5 Myeloische Neoplasien 79 5.6 Reaktive Läsionen 80 5.7 Übergeordnete Aspekte 82 5.7.1 Gesamtdiskordanzraten, Chronologie 82 5.7.2 Einsendematerial 83 5.7.3 Indikation zur Verschickung 85 5.7.4 Unklare Fälle in der Referenz 85 6. Zusammenfassung 87 Tabellenverzeichnis 89 Abbildungsverzeichnis 91 Anlagen 92 Literaturverzeichnis 97 Erklärung über die eigenständige Abfassung der Arbeit 10

Case Report: Graft Versus Tumor Effect After Non-Myeloablative Allogeneic Stem-Cell Transplantation in a Patient With Brentuximab-Vedotin Refractory Sezary Syndrome

Sezary Syndrome (SS) is a rare leukemic variant of primary cutaneous T-cell lymphoma. Relapsed or refractory disease is generally considered incurable by conventional therapeutic approaches, although durable responses can be achieved with novel monoclonal antibodies. Allogeneic hematopoietic stem cell transplantation (alloHSCT) may have potential value by inducing graft vs-lymphoma (GvL) effects, but there is currently no consensus regarding the timing of alloHSCT or type of conditioning regimen. Here we present the case of a male patient who achieved a complete remission (CR) of primary refractory SS after non-myeloablative alloHSCT. Patient: Two years prior to HSCT, the patient had been refractory to CHOEP-based chemotherapy, interferon, extracorporeal photopheresis (ECP), and bexarotene. Directly prior to alloHSCT brentuximab-vedotin (BV) was applied resulting in a partial remission of the skin compartment and overall in a stable disease. Prior to HSCT, flow cytometry of the bone marrow and peripheral blood showed an infiltration with T-cells positive for CD5, CD4, low CD3, low CD2 and negative for CD7, CD38, HLA-DR and CD8. The trephine biopsy showed a 7% infiltration of SS cells. The CD4:CD8 ratio in peripheral blood (pb) was massively increased at 76.67, with 63.5% of white blood cells expressing a SS immune phenotype. The conditioning regimen included 30 mg/m2 fludarabine on days -5, -4 and -3 and total body irradiation with 2 Gy on day -1. Immunosuppression consisted of cyclosporine A from day-1 and mycophenolate mofetil from day 0. The patient received 6.55x106 CD34+ cells and 1.11x108 CD3+ cells/kg body weight. Bone marrow evaluation on day 28 still showed persistent SS cells by flow cytometry. After tapering immunosuppression until day 169, the CD4:CD8 ratio in pb normalized. CR was documented on day 169 after alloHSCT and is now ongoing for almost 3 years after alloHSCT. Conclusions: We confirm that an alloHSCT can be a curative option for refractory patients with SS. The achievement of a CR after tapering the immunosuppressive therapy indicates a significant role of the GvL effect. In present treatment algorithms for patients with SS, the timing of an alloHSCT and the intensity of conditioning should be further explored

Characterization and outcome of post-transplant lymphoproliferative disorders within a collaborative study

BackgroundPost-transplant lymphoproliferative disorders (PTLD) are heterogeneous lymphoid disorders ranging from indolent polyclonal proliferations to aggressive lymphomas that can arise after solid organ transplantation (SOT) and allogeneic hematopoietic transplantation (allo-HSCT).MethodsIn this multi-center retrospective study, we compare patient characteristics, therapies, and outcomes of PTLD after allo-HSCT and SOT. Twenty-five patients (15 after allo-HSCT and 10 after SOT) were identified who developed PTLD between 2008 and 2022.ResultsMedian age (57 years; range, 29-74 years) and baseline characteristics were comparable between the two groups (allo-HSCT vs SOT), but median onset of PTLD was markedly shorter after allo-HSCT (2 months vs. 99 months, P<0.001). Treatment regimens were heterogeneous, with reduction of immunosuppression in combination with rituximab being the most common first-line treatment strategy in both cohorts (allo-HSCT: 66%; SOT: 80%). The overall response rate was lower in the allo-HSCT (67%) as compared to the SOT group (100%). Consequently, the overall survival (OS) trended towards a worse outcome for the allo-HSCT group (1-year OS: 54% vs. 78%; P=0.58). We identified PTLD onset ≤150 days in the allo-HSCT (P=0.046) and ECOG >2 in the SOT group (P=0.03) as prognostic factors for lower OS.ConclusionPTLD cases present heterogeneously and pose unique challenges after both types of allogeneic transplantation

Salvage Therapy With Polatuzumab Vedotin, Bendamustine, and Rituximab Prior to Allogeneic Hematopoietic Transplantation in Patients With Aggressive Lymphomas Relapsing After Therapy With Chimeric Antigen Receptor T-Cells—Report on Two Cases

Up to 60% of patients with aggressive B-cell lymphoma who receive chimeric antigen receptor (CAR) T-cell therapy experience treatment failure and subsequently have a poor prognosis. Allogeneic hematopoietic stem cell transplantation (alloHSCT) remains a potentially curative approach for patients in this situation. Induction of a deep response prior to alloHSCT is crucial for long-term outcomes, but the optimal bridging strategy following relapse after CAR T-cell therapy has not yet been established. Polatuzumab vedotin, an antibody drug conjugate targeting CD79b, is a novel treatment option for use in combination with rituximab and bendamustine (Pola-BR) in relapsed or refractory disease. Patients: We report two heavily pretreated patients with primary refractory diffuse large Bcell lymphoma (DLBCL) and primary mediastinal B-cell lymphoma (PMBCL) respectively who relapsed after therapy with CAR T-cells with both nodal and extranodal manifestations of the disease. After application of three courses of Pola-BR both patients achieved a complete metabolic remission. Both patients underwent alloHSCT from a human leukocyte antigen (HLA)-mismatched donor following conditioning with busulfan and fludarabine and are disease free 362 days and 195 days after alloHSCT respectively. We conclude that Pola-BR can be an effective bridging therapy before alloHSCT of patients relapsing after CAR T-cell therapy. Further studies will be necessary to define the depth and durability of remission of this salvage regimen before alloHSCT

The Pheno- and Genotypic Characterization of Porcine Escherichia coli Isolates

Escherichia (E.) coli is the main causative pathogen of neonatal and post-weaning diarrhea and edema disease in swine production. There is a significant health concern due to an increasing number of human infections associated with food and/or environmental-borne pathogenic and multidrug-resistant E. coli worldwide. Monitoring the presence of pathogenic and antimicrobial-resistant E. coli isolates is essential for sustainable disease management in livestock and human medicine. A total of 102 E. coli isolates of diseased pigs were characterized by antimicrobial and biocide susceptibility testing. Antimicrobial resistance genes, including mobile colistin resistance genes, were analyzed by PCR and DNA sequencing. The quinolone resistance-determining regions of gyrA and parC in ciprofloxacin-resistant isolates were analyzed. Clonal relatedness was investigated by two-locus sequence typing (CH clonotyping). Phylotyping was performed by the Clermont multiplex PCR method. Virulence determinants were analyzed by customized DNA-based microarray technology developed in this study for fast and economic molecular multiplex typing. Thirty-five isolates were selected for whole-genome sequence-based analysis. Most isolates were resistant to ampicillin and tetracycline. Twenty-one isolates displayed an ESBL phenotype and one isolate an AmpC β-lactamase-producing phenotype. Three isolates had elevated colistin minimal inhibitory concentrations and carried the mcr-1 gene. Thirty-seven isolates displayed a multi-drug resistance phenotype. The most predominant β-lactamase gene classes were blaTEM-1 (56%) and blaCTX-M-1 (13.71%). Mutations in QRDR were observed in 14 ciprofloxacin-resistant isolates. CH clonotyping divided all isolates into 51 CH clonotypes. The majority of isolates belonged to phylogroup A. Sixty-four isolates could be assigned to defined pathotypes wherefrom UPEC was predominant. WGS revealed that the most predominant sequence type was ST100, followed by ST10. ST131 was detected twice in our analysis. This study highlights the importance of monitoring antimicrobial resistance and virulence properties of porcine E. coli isolates. This can be achieved by applying reliable, fast, economic and easy to perform technologies such as DNA-based microarray typing. The presence of high-risk pathogenic multi-drug resistant zoonotic clones, as well as those that are resistant to critically important antibiotics for humans, can pose a risk to public health. Improved protocols may be developed in swine farms for preventing infections, as well as the maintenance and distribution of the causative isolates

The Pheno- and Genotypic Characterization of Porcine Escherichia coli Isolates

Escherichia (E.) coli is the main causative pathogen of neonatal and post-weaning diarrhea and edema disease in swine production. There is a significant health concern due to an increasing number of human infections associated with food and/or environmental-borne pathogenic and multidrug-resistant E. coli worldwide. Monitoring the presence of pathogenic and antimicrobial-resistant E. coli isolates is essential for sustainable disease management in livestock and human medicine. A total of 102 E. coli isolates of diseased pigs were characterized by antimicrobial and biocide susceptibility testing. Antimicrobial resistance genes, including mobile colistin resistance genes, were analyzed by PCR and DNA sequencing. The quinolone resistance-determining regions of gyrA and parC in ciprofloxacin-resistant isolates were analyzed. Clonal relatedness was investigated by two-locus sequence typing (CH clonotyping). Phylotyping was performed by the Clermont multiplex PCR method. Virulence determinants were analyzed by customized DNA-based microarray technology developed in this study for fast and economic molecular multiplex typing. Thirty-five isolates were selected for whole-genome sequence-based analysis. Most isolates were resistant to ampicillin and tetracycline. Twenty-one isolates displayed an ESBL phenotype and one isolate an AmpC β-lactamase-producing phenotype. Three isolates had elevated colistin minimal inhibitory concentrations and carried the mcr-1 gene. Thirty-seven isolates displayed a multi-drug resistance phenotype. The most predominant β-lactamase gene classes were blaTEM-1 (56%) and blaCTX-M-1 (13.71%). Mutations in QRDR were observed in 14 ciprofloxacin-resistant isolates. CH clonotyping divided all isolates into 51 CH clonotypes. The majority of isolates belonged to phylogroup A. Sixty-four isolates could be assigned to defined pathotypes wherefrom UPEC was predominant. WGS revealed that the most predominant sequence type was ST100, followed by ST10. ST131 was detected twice in our analysis. This study highlights the importance of monitoring antimicrobial resistance and virulence properties of porcine E. coli isolates. This can be achieved by applying reliable, fast, economic and easy to perform technologies such as DNA-based microarray typing. The presence of high-risk pathogenic multi-drug resistant zoonotic clones, as well as those that are resistant to critically important antibiotics for humans, can pose a risk to public health. Improved protocols may be developed in swine farms for preventing infections, as well as the maintenance and distribution of the causative isolates

Referenzbegutachtung als Instrument der Qualitätssicherung in der hämatopathologischen Diagnostik: Konkordanzraten am Universitätsklinikum Leipzig in den Jahren 2013-2018

Dem Fach Pathologie kommt eine zentrale Bedeutung in der Diagnostik und Therapie insbesondere maligner Erkrankungen zu, da die korrekte Diagnose eines Tumorleidens und des Stadiums der Tumorausbreitung die Grundlage für die weiterführende Therapie darstellt. Die Referenzbefundung ist ein Instrument, welches bei schwierigen oder seltenen Fällen eine spezialisierte histopathologische und molekularpathologische Diagnostik ermöglicht. Maligne Lymphome und myeloische Neoplasien gehören zu den am schwierigsten zu diagnostizierenden Tumorerkrankungen. Ziel der Arbeit war, alle hämatopathologischen Fälle aus der Routinediagnostik der Jahre 2013 – 2018 des Institutes für Pathologie, Universitätsklinikum Leipzig, welche zur referenzpathologischen Zweitbegutachtung versandt wurden, hinsichtlich der Diskordanzraten auszuwerten. Es sollte ein Vergleich der Primärdiagnose und der Referenzdiagnose sowie eine Auswertung hinsichtlich von konkordanten und diskordanten Diagnosen erfolgen.:Danksagung 1 Inhaltsverzeichnis 2 Abkürzungsverzeichnis 4 1. Einführung 6 1.1 Qualitätssicherung in der Pathologie 7 1.1.1 Präanalytik 7 1.1.2 Analytik 8 1.1.3 Postanalytik 8 1.1.4 Aspekte der Qualitätssicherung in der Hämatopathologie 9 1.2 Rationale für die pathologische Zweitbegutachtung 13 1.2.1 Lymphatische Neoplasien 13 1.2.2 Myeloische Neoplasien 16 2. Aufgabenstellung 18 3. Materialien und Methoden 19 4. Ergebnisse 24 4.1 Häufigkeiten 24 4.2 Fälle mit Primärdiagnose 25 4.2.1 B-Zell-Lymphome 25 4.2.2 T-Zell-Lymphome 34 4.2.3 Hodgkin-Lymphome 39 4.2.4 Myeloische Neoplasien 42 4.2.5 Reaktive Läsionen 45 4.2.6 Übrige Fälle 47 4.3 Fälle mit primär mehreren Differentialdiagnosen 49 4.3.1 B-Zell-Lymphome 49 4.3.2 T-Zell-Lymphome 51 4.3.3 Hodgkin-Lymphome 52 4.3.4 Myeloische Neoplasien 53 4.3.5 Reaktive Läsionen 53 4.3.6 Übrige Fälle 53 4.4 Zusammenfassende Auswertung 54 5. Diskussion 65 5.1 Literaturrecherche, Diskordanzraten 65 5.2 B-Zell-Lymphome 68 5.3 T-Zell-Lymphome 74 5.4 Hodgkin-Lymphome 77 5.5 Myeloische Neoplasien 79 5.6 Reaktive Läsionen 80 5.7 Übergeordnete Aspekte 82 5.7.1 Gesamtdiskordanzraten, Chronologie 82 5.7.2 Einsendematerial 83 5.7.3 Indikation zur Verschickung 85 5.7.4 Unklare Fälle in der Referenz 85 6. Zusammenfassung 87 Tabellenverzeichnis 89 Abbildungsverzeichnis 91 Anlagen 92 Literaturverzeichnis 97 Erklärung über die eigenständige Abfassung der Arbeit 10

Referenzbegutachtung als Instrument der Qualitätssicherung in der hämatopathologischen Diagnostik: Konkordanzraten am Universitätsklinikum Leipzig in den Jahren 2013-2018

Dem Fach Pathologie kommt eine zentrale Bedeutung in der Diagnostik und Therapie insbesondere maligner Erkrankungen zu, da die korrekte Diagnose eines Tumorleidens und des Stadiums der Tumorausbreitung die Grundlage für die weiterführende Therapie darstellt. Die Referenzbefundung ist ein Instrument, welches bei schwierigen oder seltenen Fällen eine spezialisierte histopathologische und molekularpathologische Diagnostik ermöglicht. Maligne Lymphome und myeloische Neoplasien gehören zu den am schwierigsten zu diagnostizierenden Tumorerkrankungen. Ziel der Arbeit war, alle hämatopathologischen Fälle aus der Routinediagnostik der Jahre 2013 – 2018 des Institutes für Pathologie, Universitätsklinikum Leipzig, welche zur referenzpathologischen Zweitbegutachtung versandt wurden, hinsichtlich der Diskordanzraten auszuwerten. Es sollte ein Vergleich der Primärdiagnose und der Referenzdiagnose sowie eine Auswertung hinsichtlich von konkordanten und diskordanten Diagnosen erfolgen.:Danksagung 1 Inhaltsverzeichnis 2 Abkürzungsverzeichnis 4 1. Einführung 6 1.1 Qualitätssicherung in der Pathologie 7 1.1.1 Präanalytik 7 1.1.2 Analytik 8 1.1.3 Postanalytik 8 1.1.4 Aspekte der Qualitätssicherung in der Hämatopathologie 9 1.2 Rationale für die pathologische Zweitbegutachtung 13 1.2.1 Lymphatische Neoplasien 13 1.2.2 Myeloische Neoplasien 16 2. Aufgabenstellung 18 3. Materialien und Methoden 19 4. Ergebnisse 24 4.1 Häufigkeiten 24 4.2 Fälle mit Primärdiagnose 25 4.2.1 B-Zell-Lymphome 25 4.2.2 T-Zell-Lymphome 34 4.2.3 Hodgkin-Lymphome 39 4.2.4 Myeloische Neoplasien 42 4.2.5 Reaktive Läsionen 45 4.2.6 Übrige Fälle 47 4.3 Fälle mit primär mehreren Differentialdiagnosen 49 4.3.1 B-Zell-Lymphome 49 4.3.2 T-Zell-Lymphome 51 4.3.3 Hodgkin-Lymphome 52 4.3.4 Myeloische Neoplasien 53 4.3.5 Reaktive Läsionen 53 4.3.6 Übrige Fälle 53 4.4 Zusammenfassende Auswertung 54 5. Diskussion 65 5.1 Literaturrecherche, Diskordanzraten 65 5.2 B-Zell-Lymphome 68 5.3 T-Zell-Lymphome 74 5.4 Hodgkin-Lymphome 77 5.5 Myeloische Neoplasien 79 5.6 Reaktive Läsionen 80 5.7 Übergeordnete Aspekte 82 5.7.1 Gesamtdiskordanzraten, Chronologie 82 5.7.2 Einsendematerial 83 5.7.3 Indikation zur Verschickung 85 5.7.4 Unklare Fälle in der Referenz 85 6. Zusammenfassung 87 Tabellenverzeichnis 89 Abbildungsverzeichnis 91 Anlagen 92 Literaturverzeichnis 97 Erklärung über die eigenständige Abfassung der Arbeit 10

Atypical presentation of patients with chronic myeloid leukemia in chronic phase: Case report

The presence of the translocation t(9;22)(q34;q11), leading to the BCR::ABL1 fusion transcript, is the hallmark of chronic myeloid leukemia (CML). Nevertheless, atypical presentation at diagnosis can be challenging. However, although most patients with CML are diagnosed with the e13a2 or e14a2 BCR:: ABL1 fusion transcripts, about 5% of them carry rare BCR::ABL1 fusion transcripts, such as e19a2, e8a2, e13a3, e14a3, e1a3, and e6a2. In particular, the e6a2 fusion transcript has been associated with clinically aggressive disease frequently presenting in accelerated or blast crisis phases. To date, there is limited evidence on the efficacy of front-line second-generation tyrosine kinase inhibitors for this genotype. Here, we report two patients, in whom the diagnosis of CML was challenging. The use of primers recognizing more distant exons from the common BCR::ABL1 breakpoint region correctly identified the atypical BCR::ABL1 e6a2 fusion transcript. Treatment with the second-generation tyrosine kinase inhibitor nilotinib was effective in our patient expressing the atypical e6a2 BCR::ABL1 fusion transcript