[FLT3-ITD mutation-positive acute myeloid leukemia undergoing clonal transition with PTPN11 mutation at relapse].

A 28-year-old man was diagnosed with acute myelomonocytic leukemia. He achieved complete remission (CR) after two cycles of induction therapy. However, after consolidation therapy, bone marrow aspiration performed to prepare for allogeneic hematopoietic stem cell transplantation revealed disease relapse. Companion diagnostics confirmed the presence of the FLT3-ITD mutation. The patient received gilteritinib monotherapy and achieved CR. Subsequently, he underwent unrelated allogeneic bone marrow transplantation. One year after transplantation, the patient relapsed, and gilteritinib was resumed. However, the leukemia progressed, and panel sequencing using a next-generation sequencer showed that the FLT3-ITD mutation disappeared. A mutation in PTPN11, which regulates the RAS/MAPK signaling pathway, was also detected. Gilteritinib was discontinued, and the patient achieved CR with salvage chemotherapy. He underwent related haploidentical peripheral blood stem cell transplantation but died of relapse. This was a case in which genetic analysis revealed clonal transition and acquisition of resistance to treatment.

[Ruptured mycotic cerebral aneurysm in an adult T-cell leukemia/lymphoma patient undergoing allogeneic stem cell transplantation].

A 63-year-old man with adult T-cell leukemia-lymphoma underwent allogeneic bone marrow transplantation from an HLA-matched unrelated donor. On day 17 after transplantation, chest computed tomography (CT) showed nodules in the lower lobes of both lungs, and invasive pulmonary aspergillosis (IPA) was suspected. Treatment with liposomal amphotericin B was started, and improvement of infectious lesions was confirmed with CT on day 28. The antifungal agent was changed to voriconazole on day 52 because of progressive renal dysfunction. Disorders of consciousness and paralysis of the left upper and lower extremities developed on day 61. Brain CT showed subcortical hemorrhage in the right parietal and occipital lobes, and the patient died on day 62. An autopsy revealed filamentous fungi, suspected to be Aspergillus, in the pulmonary nodules and a ruptured cerebral aneurysm. Although IPA occurs in 10% of transplant recipients, vigilant monitoring for mycotic cerebral aneurysms is required to prevent hematogenous dissemination of Aspergillus, which is associated with a high mortality rate.

Elevation of Urinary Liver-Type Fatty Acid-Binding Protein Is a Harbinger of Poor Patient Prognosis after Allogeneic Stem Cell Transplantation.

Several recent studies have demonstrated that urinary levels of liver-type fatty acid-binding protein (L-FABP) can be used to stratify the prognosis of cardiac disease, cardiac intensive care unit admission, cirrhosis, and coronavirus disease 2019. Our initial prospective study revealed that urinary L-FABP (uL-FABP) was associated with a high probability of acute kidney injury after stem cell transplantation (SCT); however, the relevance of elevated uL-FABP to the prognosis of patients undergoing SCT remains to be determined. We aimed to investigate whether uL-FABP levels can be used to stratify patient prognosis after SCT. To achieve this aim, we conducted a new long-term follow-up study using data from patients enrolled in our preceding prospective cohort study. Patients were classified into high and low uL-FABP groups based on levels measured at baseline (ie, before initiating the conditioning regimen), using an uL-FABP cutoff of 8.4 µg/gCr, which was determined based on data from healthy adults. uL-FABP levels were also measured on days 0, 7, and 14 after SCT. Cox proportional hazard regression was used to examine the effects of each factor on survival outcomes, and Fine-Gray regression was used in the presence of competing risks. Multivariate analysis incorporating confounders was then performed for factors with P < .1 in univariate analysis. In total, 20 of 84 patients (23.8%), 57 of 84 patients (67.9%), 34 of 49 patients (69.4%), and 34 of 46 patients (73.9%) were classified into the high uL-FABP group at baseline and on days 0, 7, and 14, respectively. The 5-year overall survival (OS) rate was 23.9% in the high uL-FABP group and 68.9% in the low uL-FABP group. The multivariate analysis identified a high uL-FABP level at baseline as a significant prognostic factor for poor OS (hazard ratio [HR], 3.54; P = .002). The 5-year cumulative incidence rate for nonrelapse mortality (NRM) was 50.0% in the high uL-FABP group and 19.9% in the low uL-FABP group. In the multivariate analysis, high uL-FABP at baseline was a significant prognostic factor for NRM (HR, 3.37; P = .01). uL-FABP levels did not significantly stratify the cumulative incidence of relapse (HR, 2.13; P = .11). uL-FABP levels on days 0, 7, and 14 were not significant predictors of survival. High uL-FABP level before initiation of conditioning significantly influences OS and NRM following SCT, whereas a high uL-FABP level at any point after the conditioning regimen does not. Our results show that measuring uL-FABP level at baseline may be a simple way to predict survival in patients undergoing SCT.

[Haploidentical hematopoietic stem cell transplantation for graft failure in myelodysplastic syndrome/myeloproliferative neoplasm-unclassifiable complicated with Stenotrophomonas maltophilia bacteremia].

A 60-year-old woman with myelodysplastic syndrome/myeloproliferative neoplasm-unclassifiable underwent unrelated bone marrow transplantation from a human leukocyte antigen (HLA) 8/8 allele-matched male donor. Neutrophil engraftment was achieved on day 29. Fluorescence in situ hybridization of sex chromosomes demonstrated complete donor chimerism. The red blood cell and platelet transfusion dependence continued, and the neutrophil count decreased gradually. Despite prolonged administration of broad-spectrum antibiotics for febrile neutropenia, blood cultures on days 46 and 58 returned positive for Stenotrophomonas maltophilia (SM). Contrast-enhanced computed tomography revealed multiple nodules of septic emboli in the lungs and kidneys, suggesting a disseminated SM infection. Antibiotic therapy was conducted based on antimicrobial susceptibility testing. However, the blood cell count failed to normalize and a secondary graft failure was diagnosed. A HLA-haploidentical peripheral-blood stem-cell transplantation from the patient's son was performed on day 134 after the initial transplantation. Neutrophil engraftment was achieved on day 11. Red blood cells and platelets were also engrafted. After the resolution of the SM bacteremia, the patient was discharged on day 63. The prognosis of the SM bacteremia with neutropenia is poor. Antibiotic treatment based on antimicrobial susceptibility testing and a second transplant from an HLA-haploidentical donor likely contributed to the successful outcome in this patient.

Impact of lung function impairment after allogeneic hematopoietic stem cell transplantation.

Late-onset noninfectious pulmonary complications (LONIPC) are a major cause of morbidity and mortality after allogeneic hematopoietic stem cell transplantation (HSCT). However, the clinical impact of lung function deterioration itself in long-term adult survivors of HSCT remains to be fully investigated. This retrospective, longitudinal study aimed to investigate pulmonary function following HSCT in terms of its change and the clinical significance of its decline. We examined 167 patients who survived for at least 2 years without relapse. The median follow-up period was 10.3 years. A linear mixed-effects model showed that the slope of pulmonary function tests values, including percent vital capacity (%VC), percent forced expiratory volume in one second (%FEV1), and FEV1/forced VC ratio (FEV1%), decreased over time. The cumulative incidence of newly obstructive and restrictive lung function impairment (LFI) at 10 years was 15.7% and 19.5%, respectively. Restrictive LFI was a significant, independent risk factor for overall survival (hazard ratio 7.11, P = 0.007) and non-relapse mortality (hazard ratio 12.19, P = 0.003). Our data demonstrated that lung function declined over time after HSCT and that the decline itself had a significant impact on survival regardless of LONIPC.

[Clinical features of tuberculosis among allogeneic hematopoietic stem cell transplantation recipients].

The incidence of tuberculosis (TB) in allogeneic hematopoietic stem cell transplantation (allo-HSCT) recipients is 10-40 times higher than that in the general population, which ranges from 0.1% to 5.5%. However, the clinical features of TB among allo-HSCT recipients in Japan remain unknown. We retrospectively analyzed the incidence of TB and the clinical features of culture-positive TB among allo-HSCT recipients at our hospital between 2002 and 2018. Of 1,047 recipients, 5 (0.4%) developed pulmonary TB (with an incidence rate of 472 per 100,000 population) at a median of 1,730 (range: 586-2,526) days after allo-HSCT. Three patients had chronic graft-versus-host disease upon the onset of TB, which was well-controlled with tacrolimus and/or steroid. Three of five patients completed TB treatment, and the disease did not flare up after therapy completion. The incidence of TB was higher in allo-HSCT recipients than in the general population (0.01%, with an incidence rate of 12.3 per 100,000 population). Therefore, TB should be considered a late complication among allo-HSCT recipients.