Pursuing dynamics of minimal residual leukemic subclones in relapsed and refractory acute myeloid leukemia during conventional therapy.

BACKGROUND: Acute myeloid leukemia (AML) is characterized by clonal heterogeneity, leading to frequent relapses and drug resistance despite intensive clinical therapy. Although AML's clonal architecture has been addressed in many studies, practical monitoring of dynamic changes in those subclones during relapse and treatment is still understudied. METHOD: Fifteen longitudinal bone marrow (BM) samples were collected from three relapsed and refractory (R/R) AML patients. Using droplet digital polymerase chain reaction (ddPCR), the frequencies of patient's leukemic variants were assessed in seven cell populations that were isolated from each BM sample based on cellular phenotypes. By quantifying mutant clones at the diagnosis, remission, and relapse stages, the distribution of AML subclones was sequentially monitored. RESULTS: Minimal residual (MR) leukemic subclones exhibit heterogeneous distribution among BM cell populations, including mature leukocyte populations. During AML progression, these subclones undergo active phenotypic transitions and repopulate into distinct cell population regardless of normal hematopoiesis hierarchic order. Of these, MR subclones in progenitor populations of patient BM predominantly carry MR leukemic properties, leading to more robust expansion and stubborn persistence than those in mature populations. Moreover, a minor subset of MR leukemic subclones could be sustained at an extremely low frequency without clonal expansion during relapse. CONCLUSIONS: In this study, we observed treatment persistent MR leukemic subclones and their phenotypic changes during the treatment process of R/R AML patients. This underscores the importance of preemptive inhibition of clonal promiscuity in R/R AML, proposing a practical method for monitoring AML MR subclones.

Risk factors for resistant gram-positive bacteremia in febrile neutropenic patients with cancer.

BACKGROUND: Gram-positive bacteria are frequently resistant to empirical beta-lactams in febrile neutropenic patients with cancer. As microbiology and antibiotic susceptibility changes, we reevaluated the risk factors for resistant Gram-positive bacteremia in febrile neutropenic patients with cancer. METHODS: Episodes of bacteremic febrile neutropenia in Seoul National University Hospital from July 2019 to June 2022 were reviewed. Resistant Gram-positive bacteria were defined as a pathogen susceptible only to glycopeptide or linezolid in vitro (e.g., methicillin-resistant staphylococci, penicillin-resistant viridans streptococci, and ampicillin-resistant enterococci). Episodes were compared to identify independent risk factors for resistant Gram-positive bacteremia. RESULTS: Of 225 episodes, 78 (34.7%) involved resistant Gram-positive bacteremia. Multivariate analysis revealed that breakthrough bacteremia while being administered antibiotics (adjusted odds ratio [aOR], 6.794; 95% confidence interval [95% CI], 3.130-14.749; P < 0.001) and catheter-related infection (aOR 4.039, 95% CI 1.366-11.946; P = 0.012) were associated with resistant Gram-positive bacteremia. Chronic liver disease (aOR 0.231, 95% CI 0.059-0.905; P = 0.035) and hypotension at bacteremia (aOR 0.454, 95% CI 0.218-0.945; P = 0.035) were inversely associated with resistant Gram-positive bacteremia. CONCLUSIONS: Resistant Gram-positive bacteria should be considered in breakthrough bacteremia and catheter-related infection in febrile neutropenic patients with cancer.

Combination of acalabrutinib with lenalidomide and rituximab in relapsed/refractory aggressive B-cell non-Hodgkin lymphoma: a single-arm phase II trial.

Potential synergism between Bruton's tyrosine kinase (BTK) inhibitor and lenalidomide in treating aggressive B-cell lymphoma has been suggested. Here, the authors report a single-arm phase II clinical trial of combination of acalabrutinib, lenalidomide and rituximab (R2A) in patients with aggressive relapsed/refractory aggressive (R/R) B-cell non-Hodgkin lymphoma (NHL). The primary endpoint of this study is objective response rate (ORR), and the secondary endpoints are complete remission (CR) rate, duration of response (DoR), progression-free survival (PFS) and overall survival (OS). A total of 66 patients are enrolled mostly with diffuse large B-cell lymphoma. The ORR is 54.5% and CR rate is 31.8% meeting the primary end point. The median DoR is 12.9 months, and 1-year PFS and OS rate is 33.1% and 67.5% respectively. Adverse events (AE) are manageable with the most frequent AE being neutropenia (31.8%). Patients with MYD88 mutations, subtypes known for NF-κB activation, and high BTK expression by immunohistochemistry respond well. Overall, these results show a significant efficacy of the R2A regimen in patients with aggressive R/R B-cell NHL, with exploratory biomarkers suggesting potential associations with response. (ClinicalTrials.gov 51 identifier: NCT04094142).

Treatment outcomes and prognostic factors of patients with lymphoblastic lymphoma in East Asia.

Lymphoblastic lymphoma (LBL) is a rare, aggressive non-Hodgkin lymphoma (NHL) that has no established therapeutic approaches. The aim of this study was to investigate optimal treatments and prognostic risk models for patients with LBL in East Asia. We retrospectively examined the clinical data and treatment courses of adult patients diagnosed as LBL by WHO 2017 classification system. Median overall survival (OS) of the 78 patients with LBL was 38.3 months. There was no significant difference in OS between the patients who were treated with acute lymphoblastic leukemia (ALL)-like protocols and with NHL-like protocols (72.4 months vs 37.5 months, respectively, P = .546). The patients treated with ALL-like protocols had significantly shorter progression-free survival (PFS) (median 11.7 months for ALL-like protocols vs 27.0 months for NHL-like protocols, P = .030). A multivariable analysis found that central nervous system (CNS) prophylaxis, relapse of CNS lesions, leukemic transformation, and response to initial treatment were risk factors for OS of patients with LBL. Hematopoietic stem cell transplantation had no survival benefit, compared with chemotherapy-only treatment. Less intensive chemotherapy may be more optimal for patients in East Asia. Prophylaxis and management of CNS lesions should be emphasized throughout the treatment of LBL.

Real-world outcome of patients with extensively pretreated multiple myeloma who were treated with selinexor and dexamethasone: a Korean multicenter retrospective analysis.

The outcomes of patients with myeloma after exposed to penta-classes are extremely poor. Selinexor is the first approved exportin inhibitor for those patients, but intractable toxicities may limit its use. This retrospective study evaluated the real-world efficacy and safety of selinexor plus dexamethasone (XD) and involved 48 patients with multiple myeloma, who were treated from November 2020 to October 2022. Their median age was 64 years, and the median number of prior lines of therapy was 6. The overall response rate was 25%, and the median progression-free survival (PFS) was 2.1 months (95% confidence interval (CI), 1.7-2.5). Patients on a reduced initial dose, delayed treatment, and dose reduction had better PFS. After XD treatment failure, 17 patients received subsequent therapy and had a median PFS of 2.4 months. The median overall survival was 4.6 months (95% CI, 2.3-6.9). Among the patients, 12 (25%) and 17 (35%) experienced dose reduction and delayed treatment, respectively. Our data show that the real-world efficacy of XD treatment in heavily pretreated patients was modest and that improving treatment adherence through reducing initial doses or delaying treatments may improve patient outcomes.

Effects of tertiary palliative care on the pattern of end-of-life care in patients with hematologic malignancies in Korea.

INTRODUCTION: Patients with hematologic malignancies (HMs) often face challenges in accessing palliative care (PC) and receiving quality end-of-life (EOL) care. We examined factors associated with referrals to tertiary PC and the effects of tertiary PC on EOL care in patients with HMs. METHOD: We included patients with HMs who were admitted to a university-affiliated hospital and died during hospitalization between January 2018 and December 2021. We investigated the receipt of PC consultations, patient characteristics, and EOL care indicators. RESULTS: Overall, 487 patients were included in the analysis, with 156 (32%) undergoing PC consultation. Sex, residence, disease status, and admission purpose were factors associated with the likelihood of PC consultation, and there has been an increasing trend in the frequency of consultations in recent cases. A higher proportion of patients who received PC completed advance statements and life-sustaining treatment documents. Patients who received PC had lower rates of aggressive EOL care, including chemotherapy and intensive care unit admission, than those who did not receive PC. Notably, PC reduced the number of blood transfusions. CONCLUSION: Tertiary PC aims to reduce aggressive EOL care through patient-centered goal-of-care discussions. Therefore, there is an imperative need for concerted efforts toward seamless integration of PC.

Clinical characteristics and treatment outcomes of Asian patients with T-cell large granular lymphocytic Leukemia: a single-center analysis of 67 cases.

Large granular lymphocytic (LGL) leukemia is a clonal lymphoproliferative disorder of LGLs derived from cytotoxic T lymphocytes or natural killer cells. However, the clinical features and treatment responses are still not fully understood because of the rarity of the disease. To describe and assess a cohort of patients with T-cell large granular lymphocytic leukemia (T-LGLL). Single-center, retrospective, observational study. We retrospectively collected the clinical data of patients diagnosed with T-LGLL at Seoul National University Hospital since 2006. We included 67 patients in this study. The median age at diagnosis was 60 years. Additionally, 37 patients (55%) were symptomatic, and 25 (37%) had splenomegaly; 54 patients (81%) required treatment. Cyclophosphamide (n = 35), methotrexate (n = 25), and cyclosporin A (n = 19) were used most frequently for treatment, and their overall response rates were similar: cyclophosphamide (77%), methotrexate (64%), and cyclosporin A (63%). Splenomegaly was associated with an increased response rate to first-line therapy and a decreased complete response rate. Thrombocytopenia was associated with decreased response rates to cyclophosphamide, methotrexate, cyclosporin A, and steroids. In contrast, a high LGL number (> 2000/µL) in the peripheral blood smear was associated with increased response rates to cyclophosphamide, methotrexate, cyclosporin A, and steroids. This study describes the clinical features and treatment outcomes of patients with T-LGLL, providing valuable information for clinical decision-making regarding T-LGLL treatment.

A randomized phase II study of acyclovir for the prevention of chemotherapy-induced oral mucositis in patients undergoing autologous hematopoietic stem cell transplantation.

OBJECTIVES: To prove our hypothesis that acyclovir prophylaxis in autologous hematopoietic stem cell transplantation (AHSCT) recipients with hematologic malignancies (HM) reduces the incidence of chemotherapy-induced oral mucositis (CIOM) by inhibiting the intraoral HSV reactivation during the neutropenic period, we conducted a randomized phase II study of acyclovir for the prevention of CIOM in adult HSV sero-positive AHSCT recipients. METHODS: Patients were randomized to either the study group (acyclovir 400 mg PO bid until neutrophil engraftment) or the control group (no prophylaxis) and received AHSCT. Oral examination and sampling for HSV were performed at three timepoints of AHSCT. RESULTS: In 54 patients who were randomized (for intention-to-analysis), the incidence of CIOM was 16.0% (4/25 patients) and 58.6% (17/29 patients) in the study group and the control group, respectively (P = 0.001). In 49 patients who completed the study (for per-protocol analysis), the incidence of CIOM was 13.0% (3/23 patients) and 61.5% (16/26 patients) in the study group and the control group, respectively (P = 0.001). In addition, HSV-1 PCR positivity in the study group was significantly lower than that the control group (4.3% vs. 46.2%, P = 0.001). A strong association between the HSV-1 reactivation status and CIOM was reconfirmed. CONCLUSIONS: Prophylactic use of oral acyclovir effectively reduced the incidence of CIOM in patients with HM who were undergoing AHSCT. TRIAL REGISTRATIONS: This trial was registered at the Clinical Research Information Service in the Republic of Korea under the number KCT0003885 (registration date 03/05/2019).

A Phase II Study to Evaluate the Efficacy of Bortezomib in Combination with Thalidomide in Treatment-Naïve Waldenstrom Macroglobulinemia Patients.

Purpose: Despite the recent success of BTK inhibitors for the treatment of Waldenstrom macroglobulinemia (WM), their indefinite treatment duration ultimately tantamount to substantial financial and emotional burden. On the other hand, fixed duration of proteasome inhibitors (PI) have shown rapid and reasonable response in WM treatment. Despite the well-known synergism between PI and immunomodulatory drugs (IMiD), there is no trials evaluating such combination in WM. Materials and Methods: Based on above, we designed this phase II study to investigate the efficacy and safety of 6 cycles of 28-day bortezomib-thalidomide-dexamethasone (VTD) regimen for treatment-naïve WM. Results: A total of 15 patients were enrolled: major response rate was 64.3%, and overall response rate was 78.6%. During the median follow-up of 41 months, median progression free survival (PFS) was 13 months and overall survival 40 months. For responders, median duration of response was 13 months and median PFS 19 months. The most common AE of any grade was constipation (57.1%). The most common grade ≥3 AE was anemia (21.4%). Conclusion: All in all, we hereby provide proof-of-concept that PI + IMiD may be an attractive backbone for fixed duration treatment. It should be noted that granting the same level of access to newer drugs globally is virtually impossible. Thus efforts to develop regimens using readily available drugs to yield similar or adequate treatment outcomes should not be disregarded. In this sense, we believe our study holds its place for its novelty and eloquently addresses achieving the daunting societal quest of health equity.

Serum Erythropoietin level in anemia of elderly with unclear etiology.

Anemia is a common condition, but its causes are often unclear, especially in elderly adults. Erythropoietin (EPO) levels are known to be elevated in myelodysplastic syndrome and hematologic malignancies, but decreased in chronic benign anemia. This study aimed to investigate whether EPO levels could be used to identify underlying bone marrow diseases including malignancies, among elderly anemic patients with unclear etiology. This single centered retrospective study included patients presented with isolated anemia and had their EPO levels measured at their first visit. Patients were divided into two groups: bone marrow disease and benign etiologic anemia, based on observation and bone marrow test results. Out of 1180 patients reviewed, 81 patients with anemia of unclear etiology were identified, including 67 with benign anemia and 14 with bone marrow disease. Statistically significant difference in EPO levels between these two groups (P < 0.001) were observed. The receiver operating characteristic curve analysis showed that an EPO cut-off value of 36.4 mU/mL had a sensitivity and specificity of 92.8% and 94.0% for detecting underlying bone marrow disease, respectively. We suggest measuring serum EPO levels can aid in the early detection of benign anemia from bone marrow disease, including malignancies, with high sensitivity and specificity.

Empirical vs pre-emptive broad-spectrum antifungal therapy for acute myelogenous leukaemia in the era of antimould prophylaxis.

INTRODUCTION: This study compared clinical outcomes in patients with acute myelogenous leukaemia (AML) who developed prolonged (≥4 days) febrile neutropenia (FN) and received either empirical or pre-emptive antimould prophylaxis in order to evaluate the need for routine empirical antifungal therapy. METHODS: This retrospective study reviewed adult patients (aged ≥18 years) with AML who developed prolonged FN and received antimould prophylaxis during induction or re-induction chemotherapy at a single centre between September 2016 and December 2020. Patients were categorized into pre-emptive or empirical groups based on whether or not there was clinical evidence of invasive fungal infection (IFI) at the start of antifungal treatment, respectively. Clinical outcomes were compared between the two groups after propensity score matching (PSM). RESULTS: In total, 229 chemotherapy episodes (36 and 193 in the empirical and pre-emptive groups, respectively) were analysed. In the pre-emptive group, broad-spectrum antifungal therapy was administered in 45 (23.3%) episodes. After 1:3 PSM, there were no significant differences between the empirical and pre-emptive groups in terms of the incidence of proven or probable IFI [0/36 (0%) vs 5/97 (5.2%); P=0.323], all-cause mortality [3/36 (8.3%) vs 4/97 (4.1%); P=0.388] and IFI-related mortality [0/36 (0.0%) vs 1/45 (2.2%); P=0.556]. CONCLUSION: The differences in clinical outcomes between empirical and pre-emptive antifungal therapy in patients with AML who received antimould prophylaxis were not significant. Therefore, broad-spectrum antifungal therapy in patients receiving antimould prophylaxis may be delayed until there is clear evidence of IFI.

Pharmacological GLUT3 salvage augments the efficacy of vitamin C-induced TET2 restoration in acute myeloid leukemia.

Vitamin C has been demonstrated to regulate hematopoietic stem cell frequencies and leukemogenesis by augmenting and restoring Ten-Eleven Translocation-2 (TET2) function, potentially acting as a promising adjunctive therapeutic agent for leukemia. However, glucose transporter 3 (GLUT3) deficiency in acute myeloid leukemia (AML) impedes vitamin C uptake and abolishes the clinical benefit of vitamin C. In this study, we aimed to investigate the therapeutic value of GLUT3 restoration in AML. In vitro GLUT3 restoration was conducted with the transduction of GLUT3-overexpressing lentivirus or the pharmacological salvage with 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR) treatment to OCI-AML3, a naturally GLUT3-deficient AML cell line. The effects of GLUT3 salvage were further confirmed in patient-derived primary AML cells. Upregulation of GLUT3 expression made AML cells successfully augment TET2 activity and enhanced the vitamin C-induced anti-leukemic effect. Pharmacological GLUT3 salvage has the potential to overcome GLUT3 deficiency in AML and improves the antileukemic effect of vitamin C treatments.

Epigenetic priming improves salvage chemotherapy in diffuse large B-cell lymphoma via endogenous retrovirus-induced cGAS-STING activation.

BACKGROUND: Although most patients with diffuse large B-cell lymphoma (DLBCL) achieve complete remission after first-line rituximab-containing immunochemotherapy, up to 40% of patients relapse and require salvage therapy. Among those patients, a substantial proportion remain refractory to salvage therapy due to insufficient efficacy or intolerance of toxicities. A hypomethylating agent, 5-azacytidine, showed a chemosensitizing effect when primed before chemotherapy in lymphoma cell lines and newly diagnosed DLBCL patients. However, its potential to improve outcomes of salvage chemotherapy in DLBCL has not been investigated. RESULTS: In this study, we demonstrated the mechanism of 5-azacytidine priming as a chemosensitizer in a platinum-based salvage regimen. This chemosensitizing effect was associated with endogenous retrovirus (ERV)-induced viral mimicry responses via the cGAS-STING axis. We found deficiency of cGAS impaired the chemosensitizing effect of 5-azacytidine. Furthermore, combining vitamin C and 5-azacytidine to synergistically activate STING could be a potential remedy for insufficient priming induced by 5-azacytidine alone. CONCLUSIONS: Taken together, the chemosensitizing effect of 5-azacytidine could be exploited to overcome the limitations of the current platinum-containing salvage chemotherapy in DLBCL and the status of cGAS-STING has the potential to predict the efficacy of 5-azacytidine priming.

A pilot randomized study for optimal red cell transfusion in acute myeloid leukemia patients with intensive chemotherapy.

BACKGROUND: Although blood transfusion is fundamental throughout the course of hematologic malignancies, acute myeloid leukemia (AML) patients requiring intensive chemotherapy are left at the edges of patient blood management programs because current guidelines do not have established recommendations for red blood cell (RBC) transfusion threshold in patients treated for hematological disorders with anemia and accompanied severe thrombocytopenia. To provide answers for the trigger and doses of ideal RBC transfusion in such situation, we conducted this prospective randomized trial. MATERIALS AND METHODS: Newly diagnosed non-acute promyelocytic AML patients undergoing chemotherapy were considered eligible for enrollment. Patients were randomized into 4 groups using a 2 by 2 factorial design, according to the RBC transfusion trigger (hemoglobin [Hb], 7 vs 8 g/dL) and the number of units per transfusion episode (quantity, single vs double-unit). RESULTS: Initially 91 patients were randomized into 4 groups, but the protocol adherence rate was 90.1%. Hb trigger did not affect the amount of RBC transfusion required during treatment. Patients receiving RBC transfusion at Hb <7 g/dL used a median of 4 units of RBC (range 0-12), and those receiving transfusion at Hb <8 g/dL also used a median of 4 units of RBC (range 0-24) (p=0.305). The number of RBC units per transfusion did not affect the total amount of RBC transfusion required during treatment. AML treatment outcomes and bleeding events did not differ across the 4 groups. DISCUSSION: This study demonstrated the feasibility for restrictive RBC transfusion (Hb <7 g/dL, RBC 1 unit) in AML patients undergoing chemotherapy, regardless of chemotherapy intensity.

ML-based sequential analysis to assist selection between VMP and RD for newly diagnosed multiple myeloma.

Optimal first-line treatment that enables deeper and longer remission is crucially important for newly diagnosed multiple myeloma (NDMM). In this study, we developed the machine learning (ML) models predicting overall survival (OS) or response of the transplant-ineligible NDMM patients when treated by one of the two regimens-bortezomib plus melphalan plus prednisone (VMP) or lenalidomide plus dexamethasone (RD). Demographic and clinical characteristics obtained during diagnosis were used to train the ML models, which enabled treatment-specific risk stratification. Survival was superior when the patients were treated with the regimen to which they were low risk. The largest difference in OS was observed in the VMP-low risk & RD-high risk group, who recorded a hazard ratio of 0.15 (95% CI: 0.04-0.55) when treated with VMP vs. RD regimen. Retrospective analysis showed that the use of the ML models might have helped to improve the survival and/or response of up to 202 (39%) patients among the entire cohort (N = 514). In this manner, we believe that the ML models trained on clinical data available at diagnosis can assist the individualized selection of optimal first-line treatment for transplant-ineligible NDMM patients.

Advantage of achieving deep response following frontline daratumumab-VTd compared to VRd in transplant-eligible multiple myeloma: multicenter study.

Background: The goal of induction therapy for multiple myeloma (MM) is to achieve adequate disease control. Current guidelines favor triplet (bortezomib-lenalidomide-dexamethasone; VRd) or quadruplet regimens (daratumumab, bortezomib-thalidomide-dexamethasone; D-VTd). In the absence of a direct comparison between two treatment regimens, we conducted this study to compare the outcomes and safety of VRd and D-VTd. Methods: Newly diagnosed MM patients aged ＞18 years who underwent induction therapy followed by autologous stem cell transplantation (ASCT) between November 2020 and December 2021 were identified. Finally, patients with VRd (N=37) and those with D-VTd (N=43) were enrolled. Results: After induction, 10.8% of the VRd group showed stringent complete remission (sCR), 21.6% showed complete response (CR), 35.1% showed very good partial response (VGPR), and 32.4% showed partial response (PR). Of the D-VTd group, 9.3% showed sCR, 34.9% CR, 48.8% VGPR, and 4.2% PR (VGPR or better: 67.6% in VRd vs. 93% in D-VTd, P=0.004). After ASCT, 68.6% of the VRd group showed CR or sCR, while 90.5% of the D-VTd group showed CR or sCR (P=0.016). VRd was associated with an increased incidence of skin rash (P=0.044). Other than rashes, there were no significant differences in terms of adverse events between the two groups. Conclusion: Our study supports the use of a front-line quadruplet induction regimen containing a CD38 monoclonal antibody for transplant-eligible patients with newly diagnosed MM.

Clinical outcomes after incomplete cycles of R-CHOP for diffuse large B-cell lymphoma: 10 years' real-world experience in a single institute.

Although the current standard of care for diffuse large B-cell lymphoma (DLBCL) is six cycles of rituximab/cyclophosphamide/doxorubicin/vincristine/prednisolone combination chemotherapy (R-CHOP), a larger than expected number of patients cannot complete planned six cycles for various reasons in the real world. We aimed to evaluate the prognosis of patients with DLBCL after incomplete treatment by analyzing the chemotherapy response and survival according to the cause of discontinuation and the number of cycles. We analyzed a retrospective cohort of patients diagnosed with DLBCL who underwent incomplete cycles of R-CHOP at Seoul National University Hospital and Boramae Medical Center from January 2010 to April 2019. A total of 1183 patients were diagnosed with DLBCL, of which 260 (22%) did not complete six cycles of R-CHOP. The most common cause of discontinuation of chemotherapy was life-threatening infection, and the most common pathogen was Pneumocystis jirovecii. Overall survival (OS) and progression-free survival (PFS) were significantly better in patients who achieved complete response (CR) or partial response (PR) at the first response evaluation. Patients underwent three or more cycles of chemotherapy had a longer OS than those who did not. In patients with limited-stage disease, consolidative radiotherapy showed a significant improvement in OS and PFS. Advanced stage, high comorbidity score, and poor primary response to chemotherapy were poor prognostic factors in patients with unplanned treatment shortening. This study provides real-world outcomes for patients who could not complete the planned six cycles of R-CHOP.