Therapy of older persons with acute myeloid leukaemia

Most persons age≥60 y with acute myeloid leukaemia (AML) die from their disease. When interpreting clinical trials data from these persons one must be aware of substantial selection biases. Randomized trials of post-remission treatments can be performed upfront or after achieving defined landmarks. Both strategies have important limitations. Selection of the appropriate treatment is critical. Age, performance score, co-morbidities and frailty provide useful data to treatment selection. If an intensive remission induction therapy is appropriate, therapy with cytarabine and an anthracycline is the most common regimen. Non-intensive therapies consist of the hypo-methylating drugs azacitidine and decitabine, low-dose cytarabine and supportive care. Feasibility of doing an allotransplant in older persons with AML is increasing. However, only very few qualify. Results of cytogenetic testing are risk factor in young and old persons with AML. Adverse abnormalities are more frequent in older persons. Although data about the frequency of mutations in older persons with AML is increasing their prognostic impact is less clear than in younger subjects. Neither differences in the distribution of cytogenetic risk, mutations, nor differences in clinical risk factors between younger and older persons with AML completely explain the age-dependent outcome. Many drugs are in clinical development in older persons with AML. Their potential role in the treatment of older persons with AML remains to be defined.

A fluorescence in situ hybridization-based screen allows rapid detection of adverse cytogenetic alterations in patients with acute myeloid leukemia

In adult acute myeloid leukemia (AML), the karyotype of the leukemic cell is among the strongest prognostic factors. The Medical Research Council (MRC) and the European LeukemiaNet (ELN) classifications distinguish between favorable, intermediate and adverse cytogenetic risk patients who differ in their treatment response and overall survival. Conventional cytogenetic analyses are a mandatory component of AML diagnostics but they are time-consuming; therefore, therapeutic decisions in elderly patients are often delayed. We investigated whether a screening approach using a panel of seven fluorescence in situ hybridization (FISH) probes would allow rapid identification of adverse chromosomal changes. In a cohort of 334 AML patients, our targeted FISH screening approach identified 80% of adverse risk AML patients with a specificity of 99%. Incorporating FISH screening into diagnostic workup has the potential to accelerate risk stratification and treatment selection, particularly in older patients. This approach may allow therapeutic decisions more quickly, which benefits both patients and physicians and might save costs.

Prognostic relevance of CD163 and CD8 combined with EZH2 and gain of chromosome 18 in follicular lymphoma: a study by the Lunenburg Lymphoma Biomarker Consortium

In follicular lymphoma, studies addressing the prognostic value of microenvironment-related immunohistochemical markers and tumor cell-related genetic markers have yielded conflicting results, precluding implementation in practice. Therefore, the Lunenburg Lymphoma Biomarker Consortium performed a validation study evaluating published markers. To maximize sensitivity, an end of spectrum design was applied for 122 uniformly immunochemotherapy-treated follicular lymphoma patients retrieved from international trials and registries. The criteria were: early failure, progression or lymphoma-related death <2 years versus long remission, response duration of >5 years. Immunohistochemical staining for T cells and macrophages was performed on tissue microarrays from initial biopsies and scored with a validated computer-assisted protocol. Shallow whole-genome and deep targeted sequencing was performed on the same samples. The 96/122 cases with complete molecular and immunohistochemical data were included in the analysis. EZH2 wild-type (P=0.006), gain of chromosome 18 (P=0.002), low percentages of CD8+ cells (P=0.011) and CD163+ areas (P=0.038) were associated with early failure. No significant differences in other markers were observed, thereby refuting previous claims of their prognostic significance. Using an optimized study design, this Lunenburg Lymphoma Biomarker Consortium study substantiates wild-type EZH2 status, gain of chromosome 18, low percentages of CD8+ cells and CD163+ area as predictors of early failure to immunochemotherapy in follicular lymphoma treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP [-like]), while refuting the prognostic impact of various other markers.

Care of cancer patients at the end of life in a German university hospital: A retrospective observational study from 2014

Background

Cancer care including aggressive treatment procedures during the last phase of life in patients with incurable cancer has increasingly come under scrutiny, while integrating specialist palliative care at an early stage is regarded as indication for high quality end-of-life patient care.

Aim

To describe the demographic and clinical characteristics and the medical care provided at the end of life of cancer patients who died in a German university hospital.

Methods

Retrospective cross-sectional study on the basis of anonymized hospital data for cancer patients who died in the Munich University Hospital in 2014. Descriptive analysis and multivariate logistic regression analyses for factors influencing the administration of aggressive treatment procedures at the end of life.

Results

Overall, 532 cancer patients died. Mean age was 66.8 years, 58.5% were men. 110/532 (20.7%) decedents had hematologic malignancies and 422/532 (79.3%) a solid tumor. Patients underwent the following medical interventions in the last 7/30 days: chemotherapy (7.7%/38.3%), radiotherapy (2.6%/6.4%), resuscitation (8.5%/10.5%), surgery (15.2%/31.0%), renal replacement therapy (12.0%/16.9%), blood transfusions (21.2%/39.5%), CT scan (33.8%/60.9%). In comparison to patients with solid tumors, patients with hematologic malignancies were more likely to die in intensive care (25.4% vs. 49.1%; p = 0.001), and were also more likely to receive blood transfusions (OR 2.21; 95% CI, 1.36 to 3.58; p = 0.001) and renal replacement therapy (OR 2.65; 95% CI, 1.49 to 4.70; p = 0.001) in the last 7 days of life. Contact with the hospital palliative care team had been initiated in 161/532 patients (30.3%). In 87/161 cases (54.0%), the contact was initiated within the last week of the patient’s life.

Conclusions

Overambitious treatments are still reality at the end of life in cancer patients in hospital but patients with solid tumors and hematologic malignancies have to be differentiated. More efforts are necessary for the timely inclusion of specialist palliative care.

Thirty-Month Complete Response as a Surrogate End Point in First-Line Follicular Lymphoma Therapy: An Individual Patient-Level Analysis of Multiple Randomized Trials

Purpose Follicular lymphoma (FL) is an indolent cancer, with effective but rarely curative treatment options. As a standard study end point for first-line FL therapy, progression-free survival (PFS) requires extended follow-up (median PFS, > 7 years). To provide patients with earlier access to newer therapies, an earlier end point to expedite clinical trials is needed. Our objective was to formally assess the complete response rate at 30 months (CR30) after initiation of induction therapy as a potential surrogate end point for PFS in first-line FL therapy. Patients and Methods We analyzed individual patient data from 13 randomized multicenter trials of induction and maintenance regimens in first-line FL therapy published after 1990 and with sufficient data to evaluate whether CR30 could predict treatment effects on PFS. Correlation of the CR30 odds ratio with the PFS hazard ratio was evaluated by both linear regression (R²_WLS) and bivariate copula (R²_Copula) models. Prespecified criteria for surrogacy required either R²_WLS or R²_Copula ≥ 0.80, with a lower-bound 95% CI > 0.60. Results Data from eight induction and five maintenance randomized trials in 3,837 evaluable patients were analyzed. The prespecified surrogacy threshold was met, with an R²_WLS of 0.88 (95% CI, 0.77 to 0.96) and an R²_Copula of 0.86 (95% CI, 0.72 to 1.00). Multiple sensitivity and supplemental analyses supported the robustness of the findings. A minimum 11% absolute improvement in CR30 from a 50% control rate predicted a significant treatment effect on PFS (hazard ratio, 0.69). Conclusion This large, prospective, pooled analysis of randomized chemotherapy, immunotherapy, and chemoimmunotherapy trials demonstrates that CR30 is a surrogate end point for PFS in first-line FL treatment trials. Use of this end point may expedite therapeutic development with the intent of bringing novel therapies to this patient population years before PFS results are mature.

Characterization of Rare, Dormant, and Therapy-Resistant Cells in Acute Lymphoblastic Leukemia

Tumor relapse is associated with dismal prognosis, but responsible biological principles remain incompletely understood. To isolate and characterize relapse-inducing cells, we used genetic engineering and proliferation-sensitive dyes in patient-derived xenografts of acute lymphoblastic leukemia (ALL). We identified a rare subpopulation that resembled relapse-inducing cells with combined properties of long-term dormancy, treatment resistance, and stemness. Single-cell and bulk expression profiling revealed their similarity to primary ALL cells isolated from pediatric and adult patients at minimal residual disease (MRD). Therapeutically adverse characteristics were reversible, as resistant, dormant cells became sensitive to treatment and started proliferating when dissociated from the in vivo environment. Our data suggest that ALL patients might profit from therapeutic strategies that release MRD cells from the niche.

Variable aldehyde dehydrogenase activity and effects on chemosensitivity of primitive human leukemic cells

Aldehyde dehydrogenase (ALDH) activity is an established feature of primitive normal human hematopoietic cells, in which it has been associated with a high expression of the 1A1 isoform of ALDH. High ALDH 1A1 activity has been reported to also characterize cells that propagate malignant populations arising in other tissues, but the regulation and basis of ALDH activity in primary human leukemic cells has not been well studied. We obtained samples from patients with newly diagnosed acute myeloid leukemia (AML; n = 21) and chronic myeloid leukemia (CML; n = 8) and analyzed different phenotypically and functionally defined subsets for their ALDH activity using the ALDEFLUOR^® kit and expression of the ALDH1A1 gene. We detected cells with high ALDH activity (ALDH^pos) in all samples from AML and CML patients. These were consistently enriched in the CD34⁺ population of these samples, but typically not in the CD34⁺CD38^- subset. Leukemic cells with direct clonogenic activity in vitro or those able to repopulate the bone marrow of sublethally irradiated non-obese diabetic (NOD)/severe combined immunodeficiency (SCID) mice were both ALDH^pos and ALDH^neg. Interestingly, ALDH1A1 transcripts were highest in the ALDH^neg leukemic cells and, in studies with leukemic cell lines, exposure to an inhibitor of ALDH activity variably affected sensitivity to daunorubicin. Cells with high ALDH activity are commonly found within the CD34⁺ population of primary human leukemic cells but, unlike in normal hematopoietic tissues, do not selectively or consistently comprise those with proliferative potential or other distinct functional properties.

Abstract B002: TLR7/8-matured dendritic cells for therapeutic vaccination in AML: Results of a clinical Phase I/II trial

Postremission therapy for acute myeloid leukemia (AML) is critical for elimination of minimal residual disease (MRD). In patients not eligible for allogeneic stem cell transplantation, alternative treatment options are needed. Therapeutic vaccination with autologous dendritic cells (DCs) loaded with leukemia-associated antigens (LAAs) is a promising treatment strategy to induce anti-leukemic immune responses and to eradicate chemorefractory cells. Using a TLR7/8 agonist, we have developed a GMP-compliant 3-day protocol to differentiate monocytes of intensively pretreated AML patients into highly functional, therapeutic DCs.

A phase I/II proof-of-concept study has been initiated using TLR7/8-matured DCs as postremission therapy of AML patients with a non-favorable risk profile in CR or CRi after intensive induction therapy (NCT01734304). DCs have been loaded with in vitro transcribed RNA encoding the LAAs WT1 and PRAME as well as CMVpp65 as adjuvant and surrogate antigen. Patients have been vaccinated intradermally with 5×106 DCs of each antigen species up to 10 times within 26 weeks. The primary endpoint of the phase I/II trial is feasibility and safety of the vaccination. Secondary endpoints are immunological responses and disease control.

In total, 13 patients have been enrolled into the study. The first 6 patients were analysed in phase I for safety and toxicity of the DC vaccine. No higher grade toxicities were observed during their treatment and hence phase II has been initiated. DCs of sufficient number and quality were generated from leukapheresis in 10/11 cases. DCs exhibited an immune-stimulatory profile based on high surface expression of positive costimulatory molecules, the capacity to secrete IL-12p70, the migration towards a chemokine gradient and processing and presentation of antigen. In 9/9 vaccinated patients, we observed delayed-type hypersensitivity (DTH) responses at the vaccination site, accompanied by slight erythema and indurations at the injection site, but no grade III/IV toxicities. TCR repertoire analysis by NGS revealed an enrichment of particular clonotypes at DTH sites. In addition, we detected vaccine-specific T-cell responses by multimer staining and by Interferon-gamma-ELISPOT analysis: 7/7 patients showed responses to CMVpp65 and 2/7 exhibited responses to PRAME and WT1, respectively. In an individual treatment attempt, an enrolled patient with impending relapse was treated with a combination of DC vaccination and 5-azacytidine, resulting in MRD conversion. Long-term disease control and immunological responses are studied in the ongoing phase II trial.

We conclude that vaccination with TLR7/8-matured, LAA-expressing DCs in AML is feasible, safe and induces anti-leukemia-specific immune responses in vivo.

Citation Format: Katrin Deiser, Felix S. Lichtenegger, Frauke M. Schnorfeil, Thomas Köhnke, Torben Altmann, Veit Bücklein, Christian Augsberger, Andreas Moosmann, Monika Brüggemann, Mirjam HM Heemskerk, Beate Wagner, Wolfgang Hiddemann, Iris Bigalke, Gunnar Kvalheim, Marion Subklewe. TLR7/8-matured dendritic cells for therapeutic vaccination in AML: Results of a clinical Phase I/II trial [abstract]. In: Proceedings of the Second CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; 2016 Sept 25-28; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2016;4(11 Suppl):Abstract nr B002.

Acute myeloid leukemia with del(9q) is characterized by frequent mutations of NPM1, DNMT3A, WT1 and low expression of TLE4

Deletions of the long arm of chromosome 9 [del(9q)] are a rare but recurring aberration in acute myeloid leukemia (AML). Del(9q) can be found as the sole abnormality or in combination with other cytogenetic aberrations such as t(8;21) and t(15;17). TLE1 and TLE4 were identified to be critical genes contained in the 9q region. We performed whole exome sequencing of 5 patients with del(9q) as the sole abnormality followed by targeted amplicon sequencing of 137 genes of 26 patients with del(9q) as sole or combined with other aberrations. We detected frequent mutations in NPM1 (10/26; 38%), DNMT3A (8/26; 31%), and WT1 (8/26; 31%) but only few FLT3-ITDs (2/26; 8%). All mutations affecting NPM1 and DNMT3A were exclusively identified in patients with del(9q) as the sole abnormality and were significantly more frequent compared to 111 patients classified as intermediate-II according to the European LeukemiaNet (10/14, 71% vs. 22/111, 20%; P < 0.001, 8/14, 57% vs. 26/111, 23%; P = 0.02). Furthermore, we identified DNMT3B to be rarely but recurrently targeted by truncating mutations in AML. Gene expression analysis of 13 patients with del(9q) and 454 patients with normal karyotype or various cytogenetic aberrations showed significant down regulation of TLE4 in patients with del(9q) (P = 0.02). Interestingly, downregulation of TLE4 was not limited to AML with del(9q), potentially representing a common mechanism in AML pathogenesis. Our comprehensive genetic analysis of the del(9q) subgroup reveals a unique mutational profile with the frequency of DNMT3A mutations in the del(9q) only subset being the highest reported so far in AML, indicating oncogenic cooperativity. © 2016 Wiley Periodicals, Inc.

Patients with Acute Myeloid Leukemia Admitted to Intensive Care Units: Outcome Analysis and Risk Prediction

Background

This retrospective, multicenter study aimed to reveal risk predictors for mortality in the intensive care unit (ICU) as well as survival after ICU discharge in patients with acute myeloid leukemia (AML) requiring treatment in the ICU.

Methods and Results

Multivariate analysis of data for 187 adults with AML treated in the ICU in one institution revealed the following as independent prognostic factors for death in the ICU: arterial oxygen partial pressure below 72 mmHg, active AML and systemic inflammatory response syndrome upon ICU admission, and need for hemodialysis and mechanical ventilation in the ICU. Based on these variables, we developed an ICU mortality score and validated the score in an independent cohort of 264 patients treated in the ICU in three additional tertiary hospitals. Compared with the Simplified Acute Physiology Score (SAPS) II, the Logistic Organ Dysfunction (LOD) score, and the Sequential Organ Failure Assessment (SOFA) score, our score yielded a better prediction of ICU mortality in the receiver operator characteristics (ROC) analysis (AUC = 0.913 vs. AUC = 0.710 [SAPS II], AUC = 0.708 [LOD], and 0.770 [SOFA] in the training cohort; AUC = 0.841 for the developed score vs. AUC = 0.730 [SAPSII], AUC = 0.773 [LOD], and 0.783 [SOFA] in the validation cohort). Factors predicting decreased survival after ICU discharge were as follows: relapse or refractory disease, previous allogeneic stem cell transplantation, time between hospital admission and ICU admission, time spent in ICU, impaired diuresis, Glasgow Coma Scale <8 and hematocrit of ≥25% at ICU admission. Based on these factors, an ICU survival score was created and used for risk stratification into three risk groups. This stratification discriminated distinct survival rates after ICU discharge.

Conclusions

Our data emphasize that although individual risks differ widely depending on the patient and disease status, a substantial portion of critically ill patients with AML benefit from intensive care.

Adults with Philadelphia chromosome-like acute lymphoblastic leukemia frequently have IGH-CRLF2 and JAK2 mutations, persistence of minimal residual disease and poor prognosis

Philadelphia-like B-cell precursor acute lymphoblastic leukemia (Ph-like ALL) is characterized by distinct genetic alterations and inferior prognosis in children and younger adults. The purpose of this study was a genetic and clinical characterization of Ph-like ALL in adults. Twenty-six (13%) of 207 adult patients (median age: 42 years) with B-cell precursor ALL (BCP-ALL) were classified as having Ph-like ALL using gene expression profiling. The frequency of Ph-like ALL was 27% among 95 BCP-ALL patients negative for BCR-ABL1 and KMT2A-rearrangements. IGH-CRLF2 rearrangements (6/16; P=0.002) and mutations in JAK2 (7/16; P<0.001) were found exclusively in the Ph-like ALL subgroup. Clinical and outcome analyses were restricted to patients treated in German Multicenter Study Group for Adult ALL (GMALL) trials 06/99 and 07/03 (n=107). The complete remission rate was 100% among both Ph-like ALL patients (n=19) and the "remaining BCP-ALL" cases (n=40), i.e. patients negative for BCR-ABL1 and KMT2A-rearrangements and the Ph-like subtype. Significantly fewer Ph-like ALL patients reached molecular complete remission (33% versus 79%; P=0.02) and had a lower probability of continuous complete remission (26% versus 60%; P=0.03) and overall survival (22% versus 64%; P=0.006) at 5 years compared to the remaining BCP-ALL patients. The profile of genetic lesions in adults with Ph-like ALL, including older adults, resembles that of pediatric Ph-like ALL and differs from the profile in the remaining BCP-ALL. Our study is the first to demonstrate that Ph-like ALL is associated with inferior outcomes in intensively treated older adult patients. Ph-like adult ALL should be recognized as a distinct, high-risk entity and further research on improved diagnostic and therapeutic approaches is needed. (NCT00199056, NCT00198991).

Addition of high-dose cytarabine to immunochemotherapy before autologous stem-cell transplantation in patients aged 65 years or younger with mantle cell lymphoma (MCL Younger): a randomised, open-label, phase 3 trial of the European Mantle Cell Lymphoma Network

BACKGROUND

Mantle cell lymphoma is characterised by a poor long-term prognosis. The European Mantle Cell Lymphoma Network aimed to investigate whether the introduction of high-dose cytarabine to immunochemotherapy before autologous stem-cell transplantation (ASCT) improves outcome.

METHODS

This randomised, open-label, parallel-group, phase 3 trial was done in 128 haemato-oncological hospital departments or private practices in Germany, France, Belgium, and Poland. Patients aged 65 years or younger with untreated stage II-IV mantle cell lymphoma were centrally randomised (1:1), with computer-assisted random block selection, to receive either six courses of R-CHOP (rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone) followed by myeloablative radiochemotherapy and ASCT (control group), or six courses of alternating R-CHOP or R-DHAP (rituximab plus dexamethasone, high-dose cytarabine, and cisplatin) followed by a high-dose cytarabine-containing conditioning regimen and ASCT (cytarabine group). Patients were stratified by study group and international prognostic index. The primary outcome was time to treatment failure from randomisation to stable disease after at least four induction cycles, progression, or death from any cause. Patients with stage II-IV mantle cell lymphoma were included in the primary analysis if treatment was started according to randomisation. For safety analyses, patients were assessed according to the treatment actually started. This study is registered with ClinicalTrials.gov, number NCT00209222.

FINDINGS

Of 497 patients (median age 55 years [IQR 49-60]) randomised from July 20, 2004, to March 18, 2010, 234 of 249 in the control group and 232 of 248 in the cytarabine group were included in the primary analysis. After a median follow-up of 6.1 years (95% CI 5.4-6.4), time to treatment failure was significantly longer in the cytarabine group (median 9.1 years [95% CI 6.3-not reached], 5 year rate 65% [95% CI 57-71]) than in the control group (3.9 years [3.2-4.4], 40% [33-46]; hazard ratio 0.56; p=0.038). During induction immunochemotherapy, patients who received high-dose cytarabine had increased grade 3 or 4 haematological toxicity (haemoglobin 71 [29%] of 241m vs 19 [8%] of 227 controls; platelets 176 [73%] of 240 vs 21 [9%] of 225), grade 3 or 4 febrile neutropenia (39 [17%] of 230 vs 19 [8%] of 224), and grade 1 or 2 renal toxicity (creatinine 102 [43%] of 236 vs 22 [10%] of 224). The number of ASCT-related deaths was similar (eight [3.4%]) in both groups.

INTERPRETATION

Immunochemotherapy containing high-dose cytarabine followed by ASCT should be considered standard of care in patients aged 65 years or younger with mantle cell lymphoma.

FUNDING

European Commission, Lymphoma Research Foundation, and Roche.

Complement cascade gene expression defines novel prognostic subgroups of acute myeloid leukemia

The involvement of the complement pathway in cancer is supported by a growing body of evidence, and yet its role in acute myeloid leukemia (AML) has not been extensively studied. We examined the expression of 87 genes in the complement, coagulation, and fibrinolysis-proteolytic pathways in 374 cytogenetically normal AML samples and observed that these samples can be divided into subgroups on the basis of complement gene expression. Three complement regulatory genes were linked to poor outcome as individual factors in a multivariate analysis (CFH, CFD, and SERPING1) in multiple cohorts. The combined expression of these genes was significantly associated with poorer overall survival in two cohorts of patients <60 years of age, independent of other factors (p ≤ 0.0004). For patients with an intermediate molecular risk, this three-gene risk marker enabled stratification of patients into prognostic subgroups with survival ranging from 17.4% to 44.1%. Thus, the expression of complement pathway genes is linked to outcome in AML, and a three-gene risk marker may improve the risk assessment of patients.

MEIS2 Is an Oncogenic Partner in AML1-ETO-Positive AML

Homeobox genes are known to be key factors in leukemogenesis. Although the TALE family homeodomain factor Meis1 has been linked to malignancy, a role for MEIS2 is less clear. Here, we demonstrate that MEIS2 is expressed at high levels in patients with AML1-ETO-positive acute myeloid leukemia and that growth of AML1-ETO-positive leukemia depends on MEIS2 expression. In mice, MEIS2 collaborates with AML1-ETO to induce acute myeloid leukemia. MEIS2 binds strongly to the Runt domain of AML1-ETO, indicating a direct interaction between these transcription factors. High expression of MEIS2 impairs repressive DNA binding of AML1-ETO, inducing increased expression of genes such as the druggable proto-oncogene YES1. Collectively, these data describe a pivotal role for MEIS2 in AML1-ETO-induced leukemia.

Core needle biopsies and surgical excision biopsies in the diagnosis of lymphoma-experience at the Lymph Node Registry Kiel

Current guidelines of the European Society of Medical Oncology recommend surgical excision biopsies of lymph nodes for the diagnosis of lymphoma whenever possible. However, core needle biopsies are increasingly used. We aimed to understand the common practice to choose the method of biopsy in Germany. Furthermore, we wanted to understand performance of surgical excision and core needle biopsies of lymph nodes in the diagnosis of lymphoma. The files of 1510 unselected, consecutive lymph node specimens from a consultation center for lymphoma diagnosis were analyzed. Core needle biopsies were obtained frequently from lymph nodes localized in mediastinal, abdominal, retroperitoneal, or thoracic regions. Patients undergoing core needle biopsies were significantly older and suffered significantly more often from lymphoma than patients undergoing surgical excision biopsies. Although more immunohistochemical tests were ordered by the pathologist for core needle biopsies specimens than for surgical excision biopsies specimens, core needle biopsies did not yield a definite diagnosis in 8.3 % of cases, compared to 2.8 % for SEB (p = 0.0003). Restricting the analysis to cases with a final diagnosis of follicular lymphoma or diffuse large B-cell lymphoma, core needle biopsies identified a simultaneous low- and high-grade lymphoma (transformation) in 3.3 % of cases, compared to 7.6 % for surgical excision biopsies (p = 0.2317). In Germany, core needle biopsies are preferentially used in elderly patients with a high likelihood of suffering from lymphoma. Core needle appeared inferior to surgical excision biopsies at providing a definite diagnosis and at identifying multiple lymphoma differentiations and transformation.

Close correlation of copy number aberrations detected by next-generation sequencing with results from routine cytogenetics in acute myeloid leukemia

High throughput sequencing approaches, including the analysis of exomes or gene panels, are widely used and established to detect tumor-specific sequence variants such as point mutations or small insertions/deletions. Beyond single nucleotide resolution, sequencing data also contain information on changes in sequence coverage between samples and thus allow the detection of somatic copy number alterations (CNAs) representing gain or loss of genomic material in tumor cells arising from aneuploidy, amplifications, or deletions. To test the feasibility of CNA detection in sequencing data we analyzed the exomes of 25 paired leukemia/remission samples from acute myeloid leukemia (AML) patients with well-defined chromosomal aberrations, detected by conventional chromosomal analysis and/or molecular cytogenetics assays. Thereby, we were able to confirm chromosomal aberrations including trisomies, monosomies, and partial chromosomal deletions in 20 out of 25 samples. Comparison of CNA detection using exome, custom gene panel, and SNP array analysis showed equivalent results in five patients with variable clone size. Gene panel analysis of AML samples without matched germline control samples resulted in confirmation of cytogenetic findings in 18 out of 22 cases. In all cases with discordant findings, small clone size (<33%) was limiting for CNA detection. We detected CNAs consistent with cytogenetics in 83% of AML samples including highly correlated clone size estimation (R = 0.85), while six out of 65 cytogenetically normal AML samples exhibited CNAs apparently missed by routine cytogenetics. Overall, our results show that high throughput targeted sequencing data can be reliably used to detect copy number changes in the dominant AML clone. © 2016 Wiley Periodicals, Inc.

Prognostic Value of Ki-67 Index, Cytology, and Growth Pattern in Mantle-Cell Lymphoma: Results From Randomized Trials of the European Mantle Cell Lymphoma Network

Purpose

Mantle-cell lymphoma (MCL) is a rather aggressive B-cell malignancy whose considerable variability of individual outcome is associated with clinical characteristics (Mantle Cell Lymphoma International Prognostic Index [MIPI]). The Ki-67 index is a strong independent prognostic factor; however, the biologic MIPI (MIPI-b) distinguishes only two groups, which does not appropriately depict the clinical heterogeneity. By using the cohort from the European MCL Younger and MCL Elderly trials, we aimed to evaluate the additional prognostic impact of cytology and growth pattern and to improve risk stratification with the Ki-67 index and MIPI.

Patients and Methods

Diagnostic tumor biopsies were reviewed by the European Mantle Cell Lymphoma Pathology Panel to determine Ki-67 index by using published guidelines, cytology, and growth pattern. We evaluated prognostic effects for overall survival (OS) by Cox regression. For the cohort used for MIPI-b development (German Low-Grade Lymphoma Study Group [GLSG] 1996 and GLSG2000), we checked whether the equally weighted combination of Ki-67 index (dichotomized at the validated 30% cutoff) and MIPI risk groups was adequate and compared the prognostic power of this modified combination to MIPI and MIPI-b for the MCL Younger/MCL Elderly cohort.

Results

The Ki-67 index was assessed in 508 of 832 patients (median age, 62 years). Blastoid cytology was associated with inferior OS independently of MIPI but not independently of the Ki-67 index. Growth pattern was not independently prognostic. The modified combination of the Ki-67 index and MIPI separated four groups with 5-year OS: 85%, 72%, 43%, and 17% (P < .001) and was more discriminative than MIPI and MIPI-b.

Conclusion

Using the Ki-67 index is superior to using cytology and growth pattern as prognostic factors in MCL. The modified combination of the Ki-67 index and MIPI showed a refined risk stratification, reflecting their strong complementary prognostic effects while integrating the most relevant prognostic factors available in clinical routine.

Hyperthermia adds to trabectedin effectiveness and thermal enhancement is associated with BRCA2 degradation and impairment of DNA homologous recombination repair

The tetrahydroisoquinoline trabectedin is a marine compound with approved activity against human soft-tissue sarcoma. It exerts antiproliferative activity mainly by specific binding to the DNA and inducing DNA double-strand breaks (DSB). As homologous recombination repair (HRR)-deficient tumors are more susceptible to trabectedin, hyperthermia-mediated on-demand induction of HRR deficiency represents a novel and promising strategy to boost trabectedin treatment. For the first time, we demonstrate enhancement of trabectedin effectiveness in human sarcoma cell lines by heat and characterize cellular events and molecular mechanisms related to heat-induced effects. Hyperthermic temperatures (41.8 or 43°C) enhanced significantly trabectedin-related clonogenic cell death and G2/M cell cycle arrest followed by cell type-dependent induction of apoptosis or senescence. Heat combination increased accumulation of γH2AX foci as key marker of DSBs. Expression of BRCA2 protein, an integral protein of the HRR machinery, was significantly decreased by heat. Consequently, recruitment of downstream RAD51 to γH2AX-positive repair foci was almost abolished indicating relevant impairment of HRR by heat. Accordingly, enhancement of trabectedin effectiveness was significantly augmented in BRCA2-proficient cells by hyperthermia and alleviated in BRCA2 knockout or siRNA-transfected BRCA2 knockdown cells. In peripheral blood mononuclear cells isolated from sarcoma patients, increased numbers of nuclear γH2AX foci were detected after systemic treatment with trabectedin and hyperthermia of the tumor region. The findings establish BRCA2 degradation by heat as a key factor for a novel treatment strategy that allows targeted chemosensitization to trabectedin and other DNA damaging antitumor drugs by on-demand induction of HRR deficiency.

[Leukemia research in Germany: the Competence Network Acute and Chronic Leukemias]

The Competence Network "Acute and Chronic Leukemias" was founded in 1997 by the consolidation of the leading leukemia study groups in Germany. Key results are the development of new trials and cooperative studies, the setup of patient registries and biobanking facilities, as well as the improvement of study infrastructure. In 2003, the concept of the competence network contributed to the foundation of the European LeukemiaNet (ELN). Synergy with the ELN resulted in cooperation on a European and international level, standardization of diagnostics and treatment, and recommendations for each leukemia and interdisciplinary specialty. The ultimate goal of the network is the cure of leukemia through cooperative research.