Measurable residual disease assessment prior to allogeneic hematopoietic stem cell transplantation in acute myeloid leukemia and myelodysplastic syndromes: a 20-year monocentric study.

Patients with acute myeloid leukemia (AML) or myelodysplastic syndromes (MDS) who undergo allogeneic hematopoietic stem-cell transplantation (alloHSCT) can have divergent survival outcomes while all in morphological complete remission (CR). Techniques of measurable residual disease (MRD) have allowed us to refine their prognosis in two categories: MRD-positive and MRD-negative patients. We conducted a monocentric retrospective study (01/2000-12/2020) to assess the prognosis of pretransplant MRD status measured by multiparametric flow cytometry (MFC) and molecular biology assessed by PCR. 192 patients were included. The median follow-up period was 77 months. Among patients undergoing alloHSCT in CR, overall survival (median-OS: 130.6 vs. 16.0 months, P < 0.001), disease-free survival (median-DFS: 109.6 vs. 7.1 months, P < 0.001) and cumulative incidence of relapse (12-month CIR: 7.3% vs. 33.7%, P < 0.0001) were significantly different between MRD-negative and MRD-positive patients. Patients with discordant intermethod results had intermediate DFS. MRD-negative patients according to molecular PCR-based techniques, WT1 overexpression and MFC had longer median-DFS, compared to MRD-positive patients (P = 0.001, P < 0.001, P < 0.001, respectively). Looking into subgroups, MRD-positive patients among the ELN2017 adverse-category (P < 0.0001), myeloablative and reduced-intensity conditioning regimens (P < 0.0001, P = 0.005), < 60-year patients (P < 0.001) and AML patients (P < 0.001) were associated with lower DFS. This difference was not found in ≥ 60-year patients (P = 0.27) and MDS patients (P = 0.70). MRD-positive patients within the favorable/intermediate ELN2017 category trended toward lower DFS (P = 0.05). We confirmed that MRD status prior to alloHSCT is a strong prognostic factor for OS, DFS and CIR. Combining MFC and molecular-PCR techniques to assess MRD seems primordial as inter-method discordance can be consequential.

A Herpes Simplex Virus 1 DNA Polymerase Multidrug Resistance Mutation Identified in a Patient With Immunodeficiency and Confirmed by Gene Editing.

BACKGROUND: Herpes simplex virus 1 can cause severe infections in individuals who are immunocompromised. In these patients, emergence of drug resistance mutations causes difficulties in infection management. METHODS: Seventeen herpes simplex virus 1 isolates were obtained from orofacial/anogenital lesions in a patient with leaky severe combined immunodeficiency over 7 years, before and after stem cell transplantation. Spatial/temporal evolution of drug resistance was characterized genotypically-with Sanger and next-generation sequencing of viral thymidine kinase (TK) and DNA polymerase (DP)-and phenotypically. CRISPR/Cas9 was used to introduce the novel DP Q727R mutation, and dual infection-competition assays were performed to assess viral fitness. RESULTS: Isolates had identical genetic backgrounds, suggesting that orofacial/anogenital infections derived from the same virus lineage. Eleven isolates proved heterogeneous TK virus populations by next-generation sequencing, undetectable by Sanger sequencing. Thirteen isolates were acyclovir resistant due to TK mutations, and the Q727R isolate additionally exhibited foscarnet/adefovir resistance. Recombinant Q727R mutant virus showed multidrug resistance and increased fitness under antiviral pressure. CONCLUSIONS: Long-term follow-up of a patient with severe combined immunodeficiency revealed virus evolution and frequent reactivation of wild-type and TK mutant strains, mostly as heterogeneous populations. The DP Q727R resistance phenotype was confirmed with CRISPR/Cas9, a useful tool to validate novel drug resistance mutations.

New Perspectives in Treating Acute Myeloid Leukemia: Driving towards a Patient-Tailored Strategy.

For decades, intensive chemotherapy (IC) has been considered the best therapeutic option for treating acute myeloid leukemia (AML), with no curative option available for patients who are not eligible for IC or who have had failed IC. Over the last few years, several new drugs have enriched the therapeutic arsenal of AML treatment for both fit and unfit patients, raising new opportunities but also new challenges. These include the already approved venetoclax, the IDH1/2 inhibitors enasidenib and ivosidenib, gemtuzumab ozogamicin, the liposomal daunorubicin/cytarabine formulation CPX-351, and oral azacitidine. Venetoclax, an anti BCL2-inhibitor, in combination with hypomethylating agents (HMAs), has markedly improved the management of unfit and elderly patients from the perspective of improved quality of life and better survival. Venetoclax is currently under investigation in combination with other old and new drugs in early phase trials. Recently developed drugs with different mechanisms of action and new technologies that have already been investigated in other settings (BiTE and CAR-T cells) are currently being explored in AML, and ongoing trials should determine promising agents, more synergic combinations, and better treatment strategies. Access to new drugs and inclusion in clinical trials should be strongly encouraged to provide scientific evidence and to define the future standard of treatment in AML.

Hepatosplenic T-cell lymphoma: treatment challenges.

PURPOSE OF REVIEW: Hepatosplenic lymphoma (HSTCL) is a rare T-cell malignancy occurring in young males, associated with immune deficiency in 20% of the cases which, despite aggressive treatments, has a poor survival. Specific recommendations for first-line treatment remain debatable. RECENT FINDINGS: Published data covering case reports or series of HSTCL concur that allogeneic stem cell transplant should be proposed as a consolidation after response to chemotherapy in all patients eligible for transplant. In the light of two recent clinical examples, we also confirm that specific chemotherapy and a first-line consolidation with allogeneic transplantation when a donor is available to represent a treatment of choice these rare and distinctive lymphomas. Recent molecular studies are summarized in this review and suggest potential targets for new therapeutic strategies. SUMMARY: Major progresses have been achieved in improving the outcome of HSTCL l patients using intensive chemotherapy and allogeneic transplantation.

Thyroid nocardiosis: Case report and review of the literature.

Disseminated nocardiosis is a rare but growing concern in immunocompromised patients. Typical localizations include the lung, brain and/or soft tissues, but laboratory confirmation of nocardiosis usually requires sampling of infected organs by invasive procedures such as bronchoalveolar lavage or brain biopsy. We report a case of disseminated nocardiosis occurring in a hematopoietic stem-cell transplant recipient, with clinical lung and brain localizations. Examination of the thyroid gland was suggestive of a unilateral abscess. A culture of thyroid pus sampled by fine-needle aspiration was positive for Nocardia farcinica and therefore avoided a more invasive procedure. The patient recovered after a six-month antibiotic therapy without thyroid surgery. We reviewed other ten cases of thyroid nocardiosis published in the medical literature. Among the ten cases of disseminated nocardiosis established during the patient's lifetime including ours, six (60%) were asymptomatic and seven (70%) were confirmed by culture of the aspiration of thyroid pus. When disseminated nocardiosis is suspected, systematic examination for a thyroid abscess may help establish a microbiological diagnosis and prevent further invasive procedures.

Risk-adapted transplant strategies for high-risk Hodgkin lymphoma: are we there?

PURPOSE OF REVIEW: The treatment of high-risk classic Hodgkin lymphoma (cHL) patients remains challenging, especially after autologous stem cell transplant (ASCT) failure. Moreover, the outcome of chemorefractory patients is still poor. RECENT FINDINGS: The development of novel targeted therapies has changed the therapeutic options for high-risk patients. To improve outcome, treatment algorithms should integrate up-front, newly established prognostic markers. Tandem ASCT instead of single ASCT has been proposed as an option to improve outcome for high-risk patients. Availability of less toxic reduced intensity conditioning regimens and recent development in haploidentical transplantation have widened applicability and improved outcomes of allo-hematopoietic cell transplantation. Their exact role in cHL is still controversial and there is no consensus on the optimal transplantation strategy. In this context, results of tandem ASCT should also be compared with those of the autologous/reduced intensity conditioning-allo tandem approach. In this review, we discuss how transplantation strategies (auto and allo) can fit into the salvage treatment plan for patients with relapsed/refractory cHL, taking into account the new drugs available and integrating modern risk assessment. SUMMARY: We speculated that improvements could be achieved by transplanting patients in earlier phases of their disease, if necessary after 'bridging' using the new drugs, and we propose an algorithm integrating the different treatment options.

High-dose therapy and autologous stem cell transplantation in first relapse for diffuse large B cell lymphoma in the rituximab era: an analysis based on data from the European Blood and Marrow Transplantation Registry.

Autologous stem cell transplantation (ASCT) consolidation remains the treatment of choice for patients with relapsed diffuse large B cell lymphoma. The impact of rituximab combined with chemotherapy in either first- or second-line therapy on the ultimate results of ASCT remains to be determined, however. This study was designed to evaluate the benefit of ASCT in patients achieving a second complete remission after salvage chemotherapy by retrospectively comparing the disease-free survival (DFS) after ASCT for each patient with the duration of the first complete remission (CR1). Between 1990 and 2005, a total of 470 patients who had undergone ASCT and reported to the European Blood and Bone Transplantation Registry with Medical Essential Data Form B information were evaluated. Of these 470 patients, 351 (74%) had not received rituximab before ASCT, and 119 (25%) had received rituximab before ASCT. The median duration of CR1 was 11 months. The median time from diagnosis to ASCT was 24 months. The BEAM protocol was the most frequently used conditioning regimen (67%). After ASCT, the 5-year overall survival was 63% (95% confidence interval, 58%-67%) and 5-year DFS was 48% (95% confidence interval, 43%-53%) for the entire patient population. Statistical analysis showed a significant increase in DFS after ASCT compared with duration of CR1 (median, 51 months versus 11 months; P < .001). This difference was also highly significant for patients with previous exposure to rituximab (median, 10 months versus not reached; P < .001) and for patients who had experienced relapse before 1 year (median, 6 months versus 47 months; P < .001). Our data indicate that ASCT can significantly increase DFS compared with the duration of CR1 in relapsed diffuse large B cell lymphoma and can alter the disease course even in patients with high-risk disease previously treated with rituximab.

Critically ill cancer patient's resuscitation: a Belgian/French societies' consensus conference.

To respond to the legitimate questions raised by the application of invasive methods of monitoring and life-support techniques in cancer patients admitted in the ICU, the European Lung Cancer Working Party and the Groupe de Recherche Respiratoire en Réanimation Onco-Hématologique, set up a consensus conference. The methodology involved a systematic literature review, experts' opinion and a final consensus conference about nine predefined questions1. Which triage criteria, in terms of complications and considering the underlying neoplastic disease and possible therapeutic limitations, should be used to guide admission of cancer patient to intensive care units?2. Which ventilatory support [High Flow Oxygenation, Non-invasive Ventilation (NIV), Invasive Mechanical Ventilation (IMV), Extra-Corporeal Membrane Oxygenation (ECMO)] should be used, for which complications and in which environment?3. Which support should be used for extra-renal purification, in which conditions and environment?4. Which haemodynamic support should be used, for which complications, and in which environment?5. Which benefit of cardiopulmonary resuscitation in cancer patients and for which complications?6. Which intensive monitoring in the context of oncologic treatment (surgery, anti-cancer treatment …)?7. What specific considerations should be taken into account in the intensive care unit?8. Based on which criteria, in terms of benefit and complications and taking into account the neoplastic disease, patients hospitalized in an intensive care unit (or equivalent) should receive cellular elements derived from the blood (red blood cells, white blood cells and platelets)?9. Which training is required for critical care doctors in charge of cancer patients?

Membrane-bound interleukin (IL)-15 on renal tumor cells rescues natural killer cells from IL-2 starvation-induced apoptosis.

Renal cell carcinoma primary tumors and lung metastases are infiltrated by activated natural killer (NK) cells. Interleukin (IL)-15, a major cytokine involved in cross-talk between accessory cells (dendritic cells and macrophages) and NK cells, is produced by epithelial renal cells. We show that renal cell carcinoma cells and normal renal cells express IL-15 mRNA and membrane-bound IL-15 (MbIL-15). These cells also express IL-15 receptor alpha (IL-15Ralpha). Silencing of IL-15Ralpha by specific small interfering RNA in renal cell carcinoma had no effect on MbIL-15 production, indicating that the cytokine is not cross-presented by IL-15Ralpha in renal cell carcinoma cells but anchored to the membrane. Furthermore, we show that MbIL-15 from renal cell carcinoma cells is functional and involved in rapid nuclear translocation of phosphorylated signal transducers and activators of transcription 3 in IL-2-starved NK cells. MbIL-15 on the target did not interfere with resting NK cell activation and target cell cytolysis but rescued NK cells from IL-2 starvation-induced apoptosis through contact-dependent interaction. Masking of MbIL-15 with soluble IL-15Ralpha molecules restored NK cell apoptosis. These findings suggest that IL-15 produced by renal tumor cells is involved in the maintenance of active NK cells at the tumor site.

Retrospective chart review of hospitalizations and costs associated with the treatment of adults with Philadelphia-negative B-cell relapsed or refractory acute lymphoblastic leukemia in Belgium.

OBJECTIVES: To quantify hospitalizations and costs among adults with Philadelphia-negative relapsed or refractory (R/R) B-cell acute lymphoblastic leukemia (ALL) who received current salvage chemotherapies in Belgium. METHODS: A retrospective chart review identified patients aged ≥18 years and hospitalized between 2005 and 2015 for Ph-negative R/R B-cell ALL. Data were collected from the index date (first diagnosis of R/R ALL) until death or loss to follow-up. The salvage chemotherapy period was defined as the first chemotherapy hospitalization after the index date to the earliest of death, loss to follow-up, last chemotherapy dose plus 30 days, or initiation of hematological stem cell transplantation (HSCT). The primary endpoint was the percent of time in the hospital during the salvage chemotherapy period. Hospitalization costs were reported from the public health care payer perspective. RESULTS: Nineteen patients were included, with median age of 37 years. The average proportion of time patients spent in the hospital during the salvage chemotherapy period was 50.5%. From the index date to death, patients received a mean of 1.8 lines of chemotherapy, most commonly hyper-CVAD (31%). There was a mean of 5.5 inpatient hospitalizations and 40.1 outpatient visits with 40.8 outpatient lab tests. Mean costs per patient were €79,973 for hospitalization (excluding HSCT), €26,337 for HSCT, €21,007 for chemotherapy drugs, and €6,341 for outpatient management, resulting in a total cost from the payer's perspective of €133,965 per patient. CONCLUSION: Adults with Ph-negative R/R ALL spend half the time receiving salvage chemotherapy in the hospital. Their treatment is associated with large reimbursement costs in Belgium.

Dissociated responses to newer antimyeloma drugs identify a subset of refractory patients with an extremely poor prognosis.

We describe the striking and unexpected evolution of 10 patients with de novo multiple myeloma treated with novel-agent based induction therapy, who displayed a dissociated evolution characterised by an apparent good response contrasting with the concomitant development of aggressive non-secreting plasmocytomas immediately before, or just after, autologous stem cell transplantation. Patients did not respond to salvage therapies. Eight of them died from progression less than 12 months after diagnosis. This unusual evolution in the era of novel agents warrants further scrutiny.

Chronic myeloid leukemia and allogeneic natural killer cells: a surprising dialogue.

Chronic myeloid leukemia (CML) is a clonal multilineage myeloproliferative disease of stem cell origin characterized by the presence of the Bcr/Abl oncoprotein, a constitutively active tyrosine kinase. The actual treatment of CML patients in chronic phase is the specific abl kinase inhibitor imatinib mesylate that induces 90% of cytogenetic responses in early-phase patients. However, resistance in long-term treated patients occurs and the allogeneic stem cell transplantation remains the only curative treatment in resistant patients. Despite recent reports outlining the role of allogeneic natural killer (NK) cells as potent antileukemic effectors, the mechanisms controlling the leukemic target recognition and lysis by activated NK cells have not been well identified. The authors' experimental data obtained on appropriate cellular models identify diverse mechanisms that could explain the increased NK-cell susceptibility of Bcr/Abl targets to NK-mediated lysis. They further delineate unexpected effects of the inhibition of the tyrosine kinase activity on the cross-talk between NK and CML leukemic cells. The consequences of such discoveries are discussed in the context of combined treatments with antikinases as well as adoptive cellular therapy approaches in myeloid leukemia patients.

The decreased susceptibility of Bcr/Abl targets to NK cell-mediated lysis in response to imatinib mesylate involves modulation of NKG2D ligands, GM1 expression, and synapse formation.

Chronic myeloid leukemia is a clonal multilineage myeloproliferative disease of stem cell origin characterized by the presence of the Bcr/Abl oncoprotein, a constitutively active tyrosine kinase. In previous studies, we have provided evidence that Bcr/Abl overexpression in leukemic cells increased their susceptibility to NK-mediated lysis by different mechanisms. In the present study, using UT-7/9 cells, a high level Bcr/Abl transfectant of UT-7 cells, we show that the treatment of Bcr/Abl target by imatinib mesylate (IM), a specific Abl tyrosine kinase inhibitor, hampers the formation of the NK/target immunological synapse. The main effect of IM involves an induction of surface GM1 ganglioside on Bcr/Abl transfectants that prevents the redistribution of MHC-related Ag molecules in lipid rafts upon interaction with NK cells. IM also affects cell surface glycosylation of targets, as assessed by binding of specific lectins resulting in the subsequent modulation of their binding to lectin type NK receptor, particularly NKG2D. In addition, we demonstrate that the tyrosine kinase activity repression results in a decrease of MHC-related Ags-A/B and UL-16-binding protein expression on Bcr/Abl transfectants UT-7/9. We show that NKG2D controls the NK-mediated lysis of UT-7/9 cells, and IM treatment inhibits this activating pathway. Taken together, our results show that the high expression of Bcr/Abl in leukemic cells controls the expression of NKG2D receptor ligands and membrane GM1 via a tyrosine kinase-dependent mechanism and that the modulation of these molecules by IM interferes with NK cell recognition and cytolysis of the transfectants.