Successful treatment of two cases with Philadelphia-chromosome positive acute lymphoblastic leukemia who relapsed after allogeneic stem cell transplantation and the treatments with novel immunotherapies and ponatinib.

The outcomes of relapsed Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ALL) resistant to new drugs such as tyrosine kinase inhibitors, inotuzumab ozogamicin (InO) and blinatumomab are dismal. We treated two cases of Ph+ALL resistant to these drugs that achieved long-term survival after treatment with chimeric antigen receptor (CAR)-T cell therapy or a second allogeneic hematopoietic stem cell transplantation (HCT) with a sequential conditioning regimen. Case 1: A 15-year-old boy was diagnosed with Ph+ALL. Despite the second HCT after the treatment of ponatinib and blinatumomab, hematological relapse occurred. InO was ineffective and he was transferred to a CAR-T center. After the CAR-T cell therapy, negative measurable residual disease (MRD) was achieved and maintained for 38 months without maintenance therapy. Case 2: A 21-year-old man was diagnosed with Ph+ALL. Hematological relapse occurred after the first HCT. Despite of the treatment with InO, ponatinib, and blinatumomab, hematological remission was not achieved. The second HCT was performed using a sequential conditioning regimen with clofarabine. Negative MRD was subsequently achieved and maintained for 42 months without maintenance therapy. These strategies are suggestive and helpful to treat Ph+ALL resistant to multiple immunotherapies.

WT1-guided pre-emptive therapy after allogeneic hematopoietic stem cell transplantation in patients with acute myeloid leukemia.

Measurable residual disease (MRD)-guided pre-emptive therapies are now widely used to prevent post-transplant hematological relapse in patients with acute myeloid leukemia (AML). This single-center retrospective study aimed to clarify the significance of pre-emptive treatment based on Wilms' tumor gene-1 mRNA (WT1) monitoring for MRD in patients with AML who underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT). Patients with AML who received chemotherapy for hematological relapse or WT1 increase after allo-HSCT were eligible for inclusion. From January 2017 to June 2022, 30 patients with a median age of 57 (16-70) years were included and stratified into two groups: 10 with WT1 increase and 20 with hematological relapse. The median times from HCT to WT1 increase or hematological relapse were 309 days (range: 48-985) or 242 days (range: 67-1116), respectively. Less intensive chemotherapy using azacitidine or cytarabine was selected for all patients with WT1 increase and 12 (60%) with hematological relapse. The 1-year overall survival and event-free survival rates for WT1 increase and hematological relapse were 70% vs. 44% (P = 0.024) and 70% vs. 29% (P = 0.029), respectively. These real-world data suggest that WT1-guided pre-emptive therapy may be superior to therapy after hematological relapse in patients with AML who have undergone allo-HSCT.

NK and T-lymphocyte Kinetics Predict Outcome in Myeloma Patients Treated With Elotuzumab, Lenalidomide Plus Dexamethasone.

Background/Aim: Elotuzumab, an anti-SLAMF7 monoclonal antibody, can enhance immune activity via elevated antibody-dependent cellular cytotoxicity and reduced SLAMF7+CD8+CD57+ regulatory T-cells (Tregs). This multicenter observational study investigated the kinetics of lymphocytes in myeloma patients treated with elotuzumab, lenalidomide, and dexamethasone (ERd) by two-color flow cytometry using peripheral blood samples. Patients and Methods: Twenty-one patients were included in this study. The median duration of ERd was 22.6 months, and the cutoff time for long-duration ERd was two years. Results: The CD2+CD16+ and CD16+CD57- NK cells were significantly increased over time in the long-duration ERd group compared to those in the short-duration ERd group (p=0.035 and p<0.001). The CD8+ and CD16-CD57+ lymphocytes, identified as low-activity NK cells or SLAMF7+ Tregs, were significantly increased in the patients whose ERd outcome was progressive disease (PD) compared to those in the non-PD group (p=0.023 and p<0.001). The mean CD4/CD8 ratio and CD19+ lymphocyte counts in the long-duration ERd group were significantly lower than those in the short-duration ERd group, although the kinetics of them did not change over time (p=0.016 and p=0.011). When the cutoff value of CD4/CD8 ratio was 0.792 according to ROC curves, the two-year time to next treatment (TTNT) in the low CD4/CD8 group was significantly longer than that in the high CD4/CD8 group (80.0% vs. 15.0%, p=0.024). Conclusion: The change in NK cells and CD8+ Tregs predicted long-duration ERd and PD, and maintaining low CD4/8 ratio predicted long TTNT, suggesting that these lymphocyte fractions might be biomarkers for a durable therapeutic effect of ERd in myeloma patients.

Pretransplantation Inflammatory and Nutritional Status in Elderly Allogeneic Hematopoietic Stem Cell Transplantation: Prognostic Value of C-Reactive Protein-to-Albumin Ratio.

There are no clear criteria for selecting elderly patients with hematologic malignancies eligible for allogeneic hematopoietic stem cell transplantation (HSCT). This study aimed to evaluate inflammatory and nutritional status biomarkers as prognostic indicators of allogeneic HSCT in elderly patients. We compared the prognostic effects of 4 representative pretransplantation biomarkers: C-reactive protein-to-albumin ratio (CAR), Glasgow Prognostic Score (GPS), prognostic nutritional index (PNI), and albumin-to-globulin ratio (AGR). A total of 143 patients age ≥60 years who underwent their first allogeneic HSCT for a hematologic malignancy were enrolled between 2010 and 2020 in our single-center cohort. The median patient age was 65 years (range, 60 to 72 years). Pretransplantation high CAR, high GPS, and low PNI scores were associated with poor overall survival (OS), but the AGR was not associated with OS. Among the 4 biomarkers, CAR stratified OS most significantly (P < .001). Multivariate analyses identified only high CAR as an independent prognostic factor associated with OS (hazard ratio [HR], 1.98; P = .031) and showed that a Hematopoietic Cell Transplantation-Specific Comorbidity Index (HCT-CI) score ≥3 also was associated with OS (HR, 2.04; P = .012). High CAR was correlated with poor performance status, male sex, and high Disease Risk Index, but not with high HCT-CI score. When the patients were stratified into 3 groups according to a composite risk assessment using CAR and HCT-CI, the 3-year OS decreased significantly with increasing scores (82.8%, 50.3%, and 27.0%, respectively; P < .0001). In conclusion, CAR is the most useful prognostic indicator among the inflammatory and nutritional status biomarkers for allogeneic HSCT in elderly patients. Inflammatory and nutritional status in the elderly may be important prognostic factors for allogeneic HSCT independent of HCT-CI score.