Event-free survival at 36 months is a suitable endpoint for diffuse large B-cell lymphoma patients treated with immunochemotherapy: real-world evidence from the North Japan Hematology Study Group.

Information regarding follow-up duration after treatment for newly diagnosed diffuse large B-cell lymphoma (DLBCL) is important. However, a clear endpoint has yet to be established. We totally enrolled 2182 patients newly diagnosed with DLBCL between 2008 and 2018. The median age of the patients was 71 years. All patients were treated with rituximab- and anthracycline-based chemotherapies. Each overall survival (OS) was compared with the age- and sex-matched Japanese general population (GP) data. At a median follow-up of 3.4 years, 985 patients experienced an event and 657 patients died. Patients who achieved an event-free survival (EFS) at 36 months (EFS36) had an OS equivalent to that of the matched GP (standard mortality ratio [SMR], 1.17; P=0.1324), whereas those who achieved an EFS24 did not have an OS comparable to that of the matched GP (SMR, 1.26; P=0.0095). Subgroup analysis revealed that relatively old patients (>60 years), male patients, those with limited-stage disease, those with a good performance status, and those with low levels of soluble interleukin 2 receptor already had a comparable life expectancy to the matched GP at an EFS24. In contrast, relatively young patients had a shorter life expectancy than matched GP, even with an EFS36. In conclusion, an EFS36 was shown to be a more suitable endpoint for newly diagnosed DLBCL patients than an EFS24. Of note, younger patients require a longer EFS period than older patients in order to obtain an equivalent life expectancy to the matched GP.

Calcineurin inhibitor inhibits tolerance induction by suppressing terminal exhaustion of donor T cells after allo-HCT.

Calcineurin inhibitor-based graft-versus-host disease (GVHD) prophylaxis is standard in allogeneic hematopoietic stem cell transplantation (HCT) but fails to induce long-term tolerance without chronic GVHD (cGVHD) in a considerable number of patients. In this study, we addressed this long-standing question in mouse models of HCT. After HCT, alloreactive donor T cells rapidly differentiated into PD-1+ TIGIT+ terminally exhausted T cells (terminal Tex). GVHD prophylaxis with cyclosporine (CSP) suppressed donor T-cell expression of TOX, a master regulator to promote differentiation of transitory exhausted T cells (transitory Tex), expressing both inhibitory receptors and effector molecules, into terminal Tex, and inhibited tolerance induction. Adoptive transfer of transitory Tex, but not terminal Tex, into secondary recipients developed cGVHD. Transitory Tex maintained alloreactivity and thus PD-1 blockade restored graft-versus-leukemia (GVL) activity of transitory Tex and not terminal Tex. In conclusion, CSP inhibits tolerance induction by suppressing the terminal exhaustion of donor T cells, while maintaining GVL effects to suppress leukemia relapse.

Reactive granulopoiesis depends on T-cell production of IL-17A and neutropenia-associated alteration of gut microbiota.

Granulopoiesis in the bone marrow adjusts cellular output as demand for neutrophils changes. Reactive granulopoiesis is induced by profound neutropenia, but its mechanism remains to be clarified. We herein explored its mechanisms using mouse models of syngeneic hematopoietic stem cell transplantation (SCT) and 5-fluorouracil-induced neutropenia. After SCT, T cell production of IL-17A was up-regulated. Neutrophil recovery was significantly delayed in IL-17A-deficient or T cell-deficient RAG1-/- mice, and adoptive transfer of wild-type (WT) T cells facilitated neutrophil engraftment. Gut decontamination with oral antibiotics suppressed T cell production of IL-17A and impaired neutrophil recovery. Transplantation of fecal microbiota collected from neutropenic, not naive, mice promoted neutrophil recovery in these mice, suggesting that neutropenia-associated microbiota had a potential to stimulate reactive granulopoiesis. Our study uncovered a cross talk between gut microbiota and neutropenia after SCT and chemotherapy.

Dynamic change in peripheral blood WT1 mRNA levels within three cycles of azacitidine predict treatment response in patients with high-risk myelodysplastic syndromes.

Azacitidine (AZA) improves overall survival (OS) in patients with high-risk myelodysplastic syndromes (MDS). However, predictive factors for response to AZA remain largely unknown. To elucidate whether dynamic change in peripheral blood (PB) Wilms' Tumor 1 (WT1) mRNA levels could predict response to AZA, we retrospectively identified 75 treatment-naïve patients with high-risk MDS who received at least 3 cycles of AZA. We classified patients into 4 groups, low-increase (LI), low-stable (LS), high-decrease (HD), and high-stable (HS) based on the dynamic change in PB WT1 mRNA levels within 3 cycles of AZA. Cumulative incidence of overall response after 10 cycles of AZA was significantly higher in LS/HD than in HS/LI (75.5% vs 4.5%, P < 0.001). The median OS for LS/HD was 18.2 months (95% CI, 12.8-28.1 months), whereas it was 11.6 months for HS/LI (95% CI, 6.6-14.1 months; P < 0.001). Multivariate analysis demonstrated that poor-/very poor-IPSS-R cytogenetic risk and HS/LI were independently associated with poor OS (poor-/very poor-IPSS-R cytogenetic risk: HR, 2.26; 95% CI, 1.10-4.68, P = 0.03, HS/LI: HR, 2.32; 95% CI, 1.21-4.46, P = 0.01). Patients with HS/LI did not show any further response to continuous AZA, and they should be considered for alternative therapy from earlier cycles.

[Successful treatment with gilteritinib for relapsed acute myeloid leukemia with FLT3-N676K mutation].

The patient was a 68-year-old woman, diagnosed with acute myelomonocytic leukemia with normal karyotype and FLT3-ITD-negative status in May 2019. She had achieved complete remission (CR) after "7+3" intensive induction chemotherapy and maintained CR by consolidation chemotherapy. However, she relapsed with swelling of the lips and gums in January 2020. She did not achieve CR by salvage chemotherapy with cytarabine-aclarubicin-G-CSF regimen. Comprehensive genomic analysis of leukemic cells revealed the presence of FLT3-N676K mutation, which was undetectable by companion diagnostics at the time. Complete remission with incomplete count recovery was obtained on day 28 after initiation of gilteritinib monotherapy, and the lip and gum swelling improved rapidly. However, she relapsed on day 106 after gilteritinib administration, and gilteritinib was discontinued. Genomic analysis at recurrence revealed NRAS mutation for the first time. Finally, the patient died of the uncontrolled primary disease. This is a case in which comprehensive gene mutation analysis was useful in determining a treatment strategy.

[Emergence of mutation in the colony-stimulating factor 3 receptor gene during follow-up of unclassifiable myeloproliferative neoplasm].

A 25-year-old male with a medical history of stress polycythemia was admitted to a previous hospital for leukocytosis, anemia, and thrombocytopenia. Bone marrow examination revealed left-shifted myeloid hyperplasia without increased blasts and normal male karyotype. No mutations of JAK2, V617F, and colony-stimulating factor 3 receptor gene (CSF3R) were detected. Fluorescence in-situ hybridization for BCR-ABL1 and FIP1L1-PDGFRA were negative. Based on these findings, a diagnosis of an unclassifiable myeloproliferative neoplasm was made, and he was started on hydroxyurea treatment. He was referred to our hospital in April 2016 for transfusion dependence. Bone marrow examination performed at our hospital revealed granulocytic dysplasia and CSF3R T618I was detected. After induction therapy, CSF3R T618I became undetectable, and he went on to undergo allogeneic stem cell transplantation in October 2016. He has been in remission for >4 years posttransplantation. CSF3R T618I is one of the genes responsible for chronic neutrophilic leukemia and atypical chronic myeloid leukemia, suggesting its involvement in the pathogenesis of this case.

Myelomonocytic differentiation of leukemic blasts accompanied by differentiation syndrome in a case of FLT3-ITD-positive AML treated with gilteritinib.

Fms-like tyrosine kinase 3 (FLT3) is one of the most frequently mutated genes in acute myelogenous leukemia (AML) and the mutation is associated with poor prognosis of patients. Two distinct types of activating mutations have been identified in AML samples. One is internal tandem duplications in the juxtamembrane domain (FLT3-ITD) and the other is point mutations in the tyrosine kinase domain (FLT3-TKD). Gilteritinib is a FLT3 inhibitor that inhibits both FLT3-ITD and FLT3-TKD. It was reported that differentiation of leukemic blasts accompanied by differentiation syndrome occurs in some patients treated with gilteritinib. However, information about the precise clinical course is limited, and appropriate management of differentiation syndrome has not been established. We report a case of relapsed AML with FLT3-ITD that was treated with gilteritinib. Analysis of the FLT3-ITD variant allele frequency (VAF) revealed that FLT3-ITD VAF was not decreased despite achievement of complete remission with incomplete hematologic recovery. Remarkable increases of monocytes and granulocytes accompanied by differentiation syndrome were observed at 6 months after the initiation of gilteritinib treatment. Intermittent chemotherapy with low-dose cytarabine and mitoxantrone was effective for reducing myelomonocytosis and resolving differentiation syndrome.

Disseminated Gonococcal Infection Associated with Eculizumab Therapy for Paroxysmal Nocturnal Hemoglobinuria: A Case Report and Literature Review.

Eculizumab has been developed as a breakthrough treatment for paroxysmal nocturnal hemoglobinuria (PNH). Not only for breakthroughs, eculizumab therapy is also known to increase the risk of invasive meningococcal infection. It has also been recently reported that, although rarely, administration of eculizumab may result in disseminated gonococcal infection (DGI). We report here a case in which a young patient who had used eculizumab for PNH developed DGI. A 22-year-old Japanese male with PNH who had been treated with eculizumab complained of high fever, mild nausea, headache and right knee joint pain. The patient was admitted and suspected to have sepsis due to meningococcal infection and began to receive ceftriaxone (CTRX). Gonococci were detected in a venous blood culture a few days later, and this case was diagnosed as DGI. CTRX was effective, and the patient was discharged. However, four weeks later, he complained of the same subjective symptoms as at the beginning and was hospitalized again. The presence of gonococcus was proven by venous blood culture, CTRX was re-administered and the patient responded. After discharge, he was counseled on safer sexual activity, including accurate and consistent use of condoms, by urologists. He has not relapsed with DGI for more than one year. When serious signs of infection occur in patients receiving eculizumab, it is recommended to consider DGI as well as invasive meningococcal infection, and CTRX should be given.

Successful Treatment of Gastrosplenic Fistula Arising from Diffuse Large B-Cell Lymphoma with Chemotherapy: Two Case Reports.

Gastrosplenic fistula (GSF) is a rare condition arising from gastric or splenic lymphomas. Surgical resection is the most common treatment, as described in previous reports. We report two cases of GSF in diffuse large B-cell lymphoma (DLBCL) patients that were successfully treated with chemotherapy and irradiation without surgical resection. Case 1 was of a 63-year-old man who had primary gastric DLBCL with a large lesion outside the stomach wall, leading to a spontaneous fistula in the spleen. Case 2 was of a 59-year-old man who had primary splenic DLBCL, which proliferated and infiltrated directly into the stomach. In both cases, chemotherapy comprising rituximab + dose-adjusted EPOCH regimen (etoposide, prednisone, vincristine, cyclophosphamide and doxorubicin) was administered. Case 1 had significant bleeding from the lesion of the stomach during the treatment cycle; however, endoscopic hemostasis was achieved. Case 2 developed a fistula between the stomach and the spleen following therapeutic chemotherapy; however, no complications related to the fistula were observed thereafter. In both cases, irradiation was administered, and complete remission was achieved.

[Takotsubo cardiomyopathy developing during anagrelide therapy in a patient with essential thrombocythemia].

A 76-year-old woman taking anagrelide (ANA) for essential thrombocythemia (ET) was rushed to the hospital by ambulance because of severe chest pain. Echocardiography revealed apical akinesis with basal and mid-hyperkinesis, and a coronary angiography revealed no significant stenosis in the dominant coronary artery. The patient was diagnosed with takotsubo cardiomyopathy (Tako). Tako is typically believed to be caused by stress; however, no stress was detected except that related to ANA therapy. ANA is useful in treating ET and is known to have severe cardiovascular effects. We must pay careful attention to Tako during ANA therapy.