Idiopathic anaphylaxis and systemic mastocytosis

A megakaryocyte in a peripheral blood smear

Promyelocyte-like blasts in B-lymphoblastic leukemia of a 67-year-old male patient

Cryoglobulinemic vasculitis with interruption of ibrutinib therapy for chronic lymphocytic leukemia (CLL) Abstract Chronic lymphocytic leukemia (CLL) can trigger autoimmune phenomena, with immune thrombocytopenia (ITP) the most common presentation. Upon cessation of CLL therapy, including ibrutinib, autoimmune flares can occur. In a 68-year-old man with CLL, ibrutinib was held for 2 weeks prior to elective shoulder surgery. Eleven days after stopping therapy, he presented with a purpuric rash on his right hip, buttock, and lower extremities. He experienced two episodes of seizure activity while hospitalized. MRI brain demonstrated patchy areas of altered signal involving deep white matter and sub-cortical white matter structures concerning for cerebral vasculitis. Although there was no evidence of hemolysis, serum cold agglutinin titer was elevated at > 1:512 and cryoglobulin levels were positive at 36%. He was diagnosed with type I cryoglobulinemia and treated with rituximab, plasmapheresis, methylprednisolone, and ibrutinib was restarted. This regimen resolved his symptoms. A rare complication of CLL is the production of cryoglobulins, which can present at initial diagnosis or in relapsed disease. Our case demonstrates that the cessation of ibrutinib therapy, even for a short time, can precipitate complications. To our knowledge, we report the first case of a patient with well-controlled CLL who rapidly developed cryoglobulinemic vasculitis after stopping ibrutinib therapy.

Supportive care for hemostatic complications associated with pediatric leukemia: a national survey in Japan Abstract Optimal supportive care for disseminated intravascular coagulation (DIC) and hemostatic complications by asparaginase is indispensable for the successful treatment of pediatric leukemia. However, the situation regarding this type of care in Japan is unclear. We conducted a questionnaire-based survey at 155 institutions treating childhood leukemia in Japan. The questionnaire asked about the supportive care provided by each institution to acute leukemia patients with DIC and asparaginase-induced hemostatic alterations. Ninety-eight institutions responded. The most common diagnostic criteria for DIC were those established by the Japanese Ministry of Health and Welfare. Regardless of the etiology underlying DIC, recombinant human thrombomodulin and synthetic protease inhibitors were used as anticoagulation therapy by around 70% and 40% of institutions, respectively. Additionally, 92%, 93%, and 73% of institutions measured plasma antithrombin, fibrinogen, and D-dimer/fibrin degradation products, respectively, more than twice per week during induction therapy for acute lymphoblastic leukemia. Survey responses indicate that 95% and 24% of the institutions used antithrombin replacement and fresh-frozen plasma, respectively. Supportive care for DIC and/or asparaginase-induced hemostatic alterations at Japanese pediatric centers was intensive and differs markedly from protocols in other countries. The efficacy of supportive care should be evaluated prospectively in the setting of pediatric leukemia.

Successful outcome with reduced-intensity condition regimen followed by allogeneic hematopoietic stem cell transplantation for relapsed or refractory anaplastic large-cell lymphoma Abstract We report a retrospective analysis of 38 patients (age ≤ 30 years) who underwent allogeneic hematopoietic stem cell transplantation (allo-SCT) for relapsed or refractory anaplastic large-cell lymphoma (ALCL). Median follow-up for survivors after undergoing allo-SCT was 72 months (range, 35–96 months). Eight patients received reduced-intensity conditioning (RIC) regimens, including three patients with fludarabine plus melphalan-based regimens and five patients with fludarabine plus busulfan-based regimens. The remaining 30 patients received myeloablative conditioning (MAC) regimens. Median ages in the RIC and MAC groups were 24 and 15 years, respectively. The 5-year overall survival rates in the RIC and MAC groups were 100% and 49%, respectively (P = 0.018). The 5-year event-free survival rates in the RIC and MAC groups were 88% and 43%, respectively (P = 0.039). In the RIC group, four of the eight patients showed residual disease at allo-SCT, but all eight patients survived with complete remission (CR), including one patient with relapse. This result suggests that allo-SCT using the RIC regimen may be effective for relapsed or refractory ALCL in children, adolescents, and young adults, even in non-CR cases.

Cessation of nilotinib in patients with chronic myelogenous leukemia who have maintained deep molecular responses for 2 years: a multicenter phase 2 trial, stop nilotinib (NILSt) Abstract The aim of this multicenter phase 2 trial, Stop Nilotinib (NILSt), was to examine the safety and efficacy of discontinuation of nilotinib in patients with chronic phase (CP)-chronic myelogenous leukemia (CML). Patients with CP-CML who had achieved molecular response (MR4.5) after initiation of imatinib or nilotinib therapy received consolidation therapy with nilotinib 300–400 mg twice daily for up to 24 months. Patients who maintained MR4.5 at 24 months of consolidation therapy proceeded to discontinuation of nilotinib. The study enrolled 149 patients; 112 patients proceeded to consolidation therapy with nilotinib; 90 patients maintained MR4.5 with consolidation therapy, and 87 proceeded to discontinuation of nilotinib. The treatment-free remission (TFR) (MR4.5) rate at both 1 and 3 years after discontinuation of nilotinib was the same, at 60.9% (90% CI 51.6–69.7). Among 34 patients with molecular relapse, nilotinib was resumed in 33 patients; all of them attained MR4.5. There was no significant association between molecular relapse and age, sex, Sokal score, previous interferon-α exposure, duration of tyrosine kinase inhibitors treatment, or trough concentration of nilotinib. With nilotinib, it might be possible to avoid prognostic factors for TFR that exist with imatinib discontinuation. Cessation of nilotinib after two years of consolidation was safe and feasible. Trial registration UMIN000007141.

Successful granulocyte apheresis using medium molecular weight hydroxyethyl starch Abstract Granulocyte transfusion (GTX) is a therapeutic option for severe bacterial or fungal infection in patients with sustained neutropenia after chemotherapy or stem cell transplantation. However, high molecular weight hydroxyethyl starch (HES), which has been used for selective sedimentation of red blood cells during apheresis, is not easily available in many countries including Japan. In this study, we evaluated the efficiency of granulocyte collection using medium molecular weight HES (130 kDa) in combination with the Spectra Optia apheresis system. Apheresis was performed for 2 consecutive days from seven donors and the mean total neutrophil yield from the first and second apheresis was 5.27 ± 3.10 × 1010 and 2.91 ± 2.92 × 1010, respectively. Infusion of concentrates from the first apheresis resulted in a significant neutrophil count increase and concentrates from the second apheresis were enough for maintenance of the neutrophil counts in all the recipients. Although the number of cases is limited, our results clearly show that sufficient number of granulocytes can be harvested by using medium molecular weight HES and this strategy is a safe and effective clinical practice in countries where high molecular weight HES is not available.

Phase I study of graft-versus-host disease prophylaxis including bortezomib for allogeneic hematopoietic cell transplantation from unrelated donors with one or two HLA loci mismatches in Japanese patients Abstract This phase I study was designed for graft-versus-host disease (GVHD) prophylaxis including bortezomib in allogeneic hematopoietic cell transplantation (allo-HCT) from human leukocyte antigen (HLA)-mismatched unrelated donors in Japanese patients. Patients were administered bortezomib on days 1, 4, and 7, with short-term methotrexate and tacrolimus. Three bortezomib dose levels were prepared (1.0, 1.3, and 1.5 mg/m2). A dose of 1.3 mg/m2 was planned for administration to the initial six patients, and was adjusted if dose-limiting toxicity developed. Five of six patients enrolled for the initial dose had bone marrow donors. Two cases had single-antigen and single-allele mismatches; four had single-antigen mismatch at the A, B, C, and/or DRB1 loci in the GVH direction. All patients achieved neutrophil engraftment and complete donor chimerism. Three patients developed grade II acute GVHD, and none developed grade III–IV GVHD or any dose-limiting toxicity attributable to bortezomib by day 100. Two patients developed late-onset acute GVHD, and two developed chronic GVHD, but all cases were manageable. All patients were alive without relapse after a median follow-up period of 52 months. The optimal dose of bortezomib was determined to be 1.3 mg/m2. Prophylaxis against GVHD using a regimen including bortezomib thus seems feasible for HLA-mismatched unrelated allo-HCT.

Efficacy and safety of quizartinib in Japanese patients with FLT3 -ITD positive relapsed or refractory acute myeloid leukemia in an open-label, phase 2 study Abstract FMS-like tyrosine kinase 3 (FLT3) internal tandem duplication (ITD) mutations in patients with acute myeloid leukemia (AML) are associated with early relapse and poor survival. This multicenter, single-arm, two-stage phase 2 study (NCT02984995) was conducted to evaluate the efficacy and safety of quizartinib hydrochloride (initial dose 20/30 mg/day), an oral, highly potent, selective FLT3 inhibitor in Japanese patients (median age 65 years) with FLT3-ITD positive relapsed/refractory (R/R) AML. The composite complete remission (CRc) rate (primary endpoint) was 53.8% (90% confidence interval 36.2–70.8%) for evaluable patients in the efficacy analysis set. The median duration of CRc and overall survival was 16.1 weeks and 34.1 weeks, respectively. The most frequent treatment-emergent adverse events (TEAEs) were febrile neutropenia (43.2%), platelet count decreased (37.8%), and QT prolonged (35.1%). Two (5.4%) patients experienced TEAEs associated with treatment discontinuation. All serious TEAEs (45.9%), except febrile neutropenia (16.2%), were reported in ≤ 2 patients. The incidence of QTcF 451–480 ms and 481–500 ms was 37.8% and 2.7%, respectively. No QTcF > 500 ms, events of torsade de pointes or arrhythmia with clinical symptoms were reported. Quizartinib monotherapy was well tolerated and resulted in clinically meaningful reductions in blast count in Japanese patients with FLT3-ITD R/R AML.