Outcomes of patients undergoing third hematopoietic cell transplantation for hematologic malignancies.

With advancements in novel therapeutics, it is unclear whether third hematopoietic cell transplantation (HCT3) has a place in the treatment of recurrent hematopoietic malignancies. We evaluated patients with hematologic malignancies who underwent HCT3 between 2000-2020. Nine patients, with a median age of 18 (9-68) years at HCT3 with acute myelogenous leukemia (n = 5), acute lymphoblastic leukemia (n = 2), myelodysplastic syndrome (n = 1), or undifferentiated acute leukemia (n = 1), were identified. The median time between first HCT and HCT3 was 3.9 (0.7-13.6) years. Indication for HCT3 was relapse (n = 8) or graft failure (n = 1) after second HCT. At HCT3, seven of nine patients were in complete remission by flow cytometry. All experienced robust donor engraftment by one month after HCT3 (≥ 90% CD3) while one died at day + 24 of multi-organ failure and was not evaluable for chimerism. In total, eight patients died from relapse (n = 4), non-relapse, (n = 3) or unknown (n = 1) causes at a median of 0.6 (range, 0.1 - 9.9) years after HCT3. After HCT3, estimated overall survival at 6 months, 1 year, and 5 years was 88%, 63%, and 22%, respectively. In this highly selected group, HCT3 provided a treatment option although long-term survival was still dismal.

Mutational landscape, clonal evolution patterns, and role of RAS mutations in relapsed acute lymphoblastic leukemia.

Although multiagent combination chemotherapy is curative in a significant fraction of childhood acute lymphoblastic leukemia (ALL) patients, 20% of cases relapse and most die because of chemorefractory disease. Here we used whole-exome and whole-genome sequencing to analyze the mutational landscape at relapse in pediatric ALL cases. These analyses identified numerous relapse-associated mutated genes intertwined in chemotherapy resistance-related protein complexes. In this context, RAS-MAPK pathway-activating mutations in the neuroblastoma RAS viral oncogene homolog (NRAS), kirsten rat sarcoma viral oncogene homolog (KRAS), and protein tyrosine phosphatase, nonreceptor type 11 (PTPN11) genes were present in 24 of 55 (44%) cases in our series. Interestingly, some leukemias showed retention or emergence of RAS mutant clones at relapse, whereas in others RAS mutant clones present at diagnosis were replaced by RAS wild-type populations, supporting a role for both positive and negative selection evolutionary pressures in clonal evolution of RAS-mutant leukemia. Consistently, functional dissection of mouse and human wild-type and mutant RAS isogenic leukemia cells demonstrated induction of methotrexate resistance but also improved the response to vincristine in mutant RAS-expressing lymphoblasts. These results highlight the central role of chemotherapy-driven selection as a central mechanism of leukemia clonal evolution in relapsed ALL, and demonstrate a previously unrecognized dual role of RAS mutations as drivers of both sensitivity and resistance to chemotherapy.

[Chimeric antigen receptor T cell (CAR-T) therapy for refractory/relapsed hematological malignancy].

Anti-tumor drugs have been the mainstay of cancer treatment; however, immunotherapy has been considered as supplementary, often less effective, and associated with toxicity. However, over the recent years, new types of immunotherapies have been developed, some of which are proving pivotal in current cancer treatment. Of these, chimeric antigen receptor T (CAR-T) cell therapy represents one of the promising types of immunotherapy, particularly for B-lineage malignancy treatment. Notably, many researchers are utilizing this technology for other types of cancer as well. Although it has some drawbacks such as lethal side-effects and extremely high costs, CAR-T cell therapy is estimated to be a potential game changer in the field of cancer treatment. This review provides an overview of the current status and future prospects of CAR-T therapy.

The Outcome of Pediatric Philadelphia Chromosome-Positive Acute Lymphoblastic Leukemia: Experience from a Referral Center in South India.

Although improved survival in children with Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph-ALL) has been demonstrated in trials, the outcome appears to be inferior in low- and middle-income countries (LMIC). Methods A file review of children aged ≤ 15 years diagnosed with Ph-ALL from 2010 to 2019 was performed. Minimal residual disease (MRD) was assessed by flow-cytometry. Real-time polymerase chain reaction (qRT-PCR) was used to quantify the BCR::ABL1 transcripts during treatment. Results The mean age of the 20 patients in the study was 91 months. Of 19 patients in whom the BCR::ABL1 transcript was confirmed, 10(50%) had P210, 7(35%) had P190, and two showed dual expression. The mean dose of imatinib that was administered was 294 ± 41 mg/m2/day. qRT-PCR for BCR::ABL1 was < 0.01% in all patients who were in remission or had a late relapse and was ≥ 0.01% in patients who had an early relapse. Two patients underwent HSCT. The 3-year event-free survival (EFS) was 35.0 ± 10.7%. Patients with a good prednisolone response (GPR) and a negative end-of-induction MRD demonstrated a superior EFS to those who lacked either or both (80.0 ± 17.9% vs. 16.7 ± 15.2%, P = 0.034). Conclusion The 3-year EFS of 20 children with Ph-ALL treated with chemotherapy and TKI was < 50%. An unusually high proportion of patients with p210 transcript expression; sub-optimal TKI dosing and lesser intensity of chemotherapy, due to the concern of high treatment-related mortality in LMIC are possible reasons for the poor outcome. Conventional treatment response parameters such as GPR and MRD predict outcomes in Ph-ALL. qRT-PCR for BCR::ABL1 may have a role in predicting early relapse. Supplementary Information: The online version contains supplementary material available at 10.1007/s12288-023-01684-9.

Treatment of Acute Lymphoid Leukemia Refractory to Classic First-Line and Rescue Protocols.

Acute Lymphoblastic Leukemia is a very aggressive malignant disorder of lymphoid cells in adults, with recurrence (30 to 60% of the cases) after the initial treatment. Until this moment, there is no gold standard therapy for the treatment of adult patients with acute relapsed/refractory lymphoblastic leukemia. In this case report, we describe two cases of relapsed leukemia: one of lymphocytic leukemia B and one of trilineage leukemia, which presented a satisfactory response to treatment with Bortezomib associated with Vincristine, Dexamethasone, and Bendamustine.

Impact of prophylactic/preemptive donor lymphocyte infusion and intensified conditioning for relapsed/refractory leukemia: a real-world study.

Prophylactic/preemptive donor lymphocyte infusion (p/pDLI) and intensified conditioning have shown promising results in experimental studies of refractory/relapsed acute leukemia (RRAL), but real-world data remain scarce. We conducted a multicenter, population-based analysis of 932 consecutive patients. The three-year leukemia-free survival (LFS) rates were 56% for patients receiving both p/pDLI and intensified myeloablative conditioning (MAC) (intenseMAC) and 30% for those who received neither therapy per landmark analysis. Multivariable analyses were run separately for acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL), and p/pDLI treatment was linked to significantly higher LFS than non-DLI for both AML and ALL patients without increasing the nonrelapse mortality. IntenseMAC was associated with significantly lower relapse and higher LFS than nonintensified MAC despite higher nonrelapse mortality rates in ALL, while there was no impact of intenseMAC observed in AML. p/pDLI achieved superior outcomes in both matched-sibling donor (MSD) and haploidentical donor transplantation, while intenseMAC only influenced MSD outcomes. Data suggest that RRAL patients receiving "total therapy" by way of p/pDLI and intensified conditioning treatment have an improved chance for LFS, with p/pDLI being safer with a more extensive impact relative to intenseMAC. Patients with RRAL can tolerate both interventions and achieve a reasonable outcome.

Efficacy of mitoxantrone-based salvage therapies in relapsed or refractory acute myeloid leukemia in the Mayo Clinic Cancer Center: Analysis of survival after 'CLAG-M' vs. 'MEC'.

Salvage therapy regimens for refractory and relapsed AML include mitoxantrone, etoposide, and cytarabine (MEC) and cladribine, cytarabine, filgrastim, and mitoxantrone (CLAG-M). We analyzed patients receiving either CLAG-M or MEC as salvage therapy for RR-AML between 09/01/2009-12/31/2017. Of 150 patients with RR-AML, 34 patients received CLAG-M and 116 MEC. CR/CRi rates for CLAG-M and MEC were 61.3 % (19/31) and 55.6 % (60/108). Median OS was 9.5 months for CLAG-M and 10.0 months for MEC (HR = 0.88,95 %CI = 0.54-1.41,p = 0.59). 76 patients proceeded to ASCT following salvage therapy. Median OS after ASCT was 13.0 months for CLAG-M and 31.0 months for MEC (HR = 1.76,95 %CI = 0.87-3.56,p = 0.12). Among those with late relapse and ASCT, median OS was 9.0 and 48.0 months for CLAG-M and MEC, respectively (HR = 17.6,95 %CI = 1.57-198,p < 0.001). There were no significant differences in outcome between CLAG-M vs. MEC regardless of transplant status. There was a significant improvement in survival in patients with late relapse treated with MEC who proceeded to ASCT.

Vincristine and prednisone regulates cellular and exosomal miR-181a expression differently within the first time diagnosed and the relapsed leukemia B cells.

We explored the effect of vincristine and prednisone on cellular and exosomal miR-181a expression in first time diagnosed leukemia and relapsed leukemia. Vincristine and prednisone induced apoptosis/pro-apoptotic genes in first time diagnosed leukemia, and suppressed the cellular and exosomal miR-181a expression. In contrast, vincristine and prednisone could not induce apoptosis/pro-apoptotic genes in relapsed leukemia, and could not change the expression of cellular or exosomal miR-181a. In conclusion, the non-suppressive nature of miR-181a in relapsed leukemia might contribute to the chemo-resistance and this suggests a potential role of miR-181a-inhibitor along with the chemotherapy in the treatment of relapsed leukemia.

18F-FDG PET/CT Radiomic Analysis with Machine Learning for Identifying Bone Marrow Involvement in the Patients with Suspected Relapsed Acute Leukemia.

18F-FDG PET / CT is used clinically for the detection of extramedullary lesions in patients with relapsed acute leukemia (AL). However, the visual analysis of 18F-FDG diffuse bone marrow uptake in detecting bone marrow involvement (BMI) in routine clinical practice is still challenging. This study aims to improve the diagnostic performance of 18F-FDG PET/CT in detecting BMI for patients with suspected relapsed AL. Methods: Forty-one patients (35 in training group and 6 in independent validation group) with suspected relapsed AL were retrospectively included in this study. All patients underwent both bone marrow biopsy (BMB) and 18F-FDG PET/CT within one week. The BMB results were used as the gold standard or real "truth" for BMI. The bone marrow 18F-FDG uptake was visually diagnosed as positive and negative by three nuclear medicine physicians. The skeletal volumes of interest were manually drawn on PET/CT images. A total of 781 PET and 1045 CT radiomic features were automatically extracted to provide a more comprehensive understanding of the embedded pattern. To select the most important and predictive features, an unsupervised consensus clustering method was first performed to analyze the feature correlations and then used to guide a random forest supervised machine learning model for feature importance analysis. Cross-validation and independent validation were conducted to justify the performance of our model. Results: The training group involved 16 BMB positive and 19 BMB negative patients. Based on the visual analysis of 18F-FDG PET, 3 patients had focal uptake, 8 patients had normal uptake, and 24 patients had diffuse uptake. The sensitivity, specificity, and accuracy of visual analysis for BMI diagnosis were 62.5%, 73.7%, and 68.6%, respectively. With the cross-validation on the training group, the machine learning model correctly predicted 31 patients in BMI. The sensitivity, specificity, and accuracy of the machine learning model in BMI detection were 87.5%, 89.5%, and 88.6%, respectively, significantly higher than the ones in visual analysis (P < 0.05). The evaluation on the independent validation group showed that the machine learning model could achieve 83.3% accuracy. Conclusions:18F-FDG PET/CT radiomic analysis with machine learning model provided a quantitative, objective and efficient mechanism for identifying BMI in the patients with suspected relapsed AL. It is suggested in particular for the diagnosis of BMI in the patients with 18F-FDG diffuse uptake patterns.

Non-malignant CSF lymphocytosis in a patient with acute lymphoblastic leukemia.

Patients with haematological malignancy are often profoundly immune suppressed, and more so if they require more than one line of therapy. Infection should always be considered when they become unwell. We discuss the differential diagnoses of a young man with multiply-relapsed Philadelphia chromosome-positive B-cell acute lymphoblastic leukaemia who presented with neurological symptoms and cerebrospinal fluid lymphocytosis. The diagnostic approach needs to be rapid and structured, and may require microbiology and neurology support.

A Phase II Study of CLAG Regimen Combined With Imatinib Mesylate for Relapsed or Refractory Acute Myeloid Leukemia.

INTRODUCTION: No standard salvage chemotherapy regimen is available for relapsed or refractory (RR) acute myeloid leukemia (AML). Preclinical data have suggested synergy in vitro between cytarabine and imatinib mesylate (IM) on AML cell growth inhibition. After demonstrating the safety and feasibility in a phase I study, we conducted a phase II clinical study of CLAG (cladribine, cytarabine, granulocyte colony-stimulating factor) regimen combined with IM for patients with RR-AML. PATIENTS AND METHODS: We performed a single-institution 2-stage phase II study. The primary endpoint was the remission rate measured using the standard AML response criteria. The secondary endpoints included overall survival (OS) and progression-free survival (PFS). RESULTS: From August 2009 to April 2011, 38 patients were treated at the Moffitt Cancer Center. Their median age was 62 years (range, 26-79 years). Of the 38 patients, 7 (18%) had refractory AML, 19 (50%) had early relapse, and 12 (32%) had late relapse. At the original diagnosis, only 2 patients had favorable risk factors, 18 had intermediate risk, and 16 had poor risk; for 2 patients, the karyotype was missing. The overall response rate for all 38 evaluable patients was 37%. The median OS was 11.1 months (95% CI, 4.8-13.4 months), the median PFS was 4.9 months (95% CI, 1.6-11.7 months). Among the responders, 8 of 14 patients subsequently underwent allogeneic hematopoietic cell transplantation. CONCLUSION: CLAG plus IM was well tolerated, with encouraging signs of activity in patients with poor-risk AML.

Beyond CD19: Opportunities for Future Development of Targeted Immunotherapy in Pediatric Relapsed-Refractory Acute Leukemia.

Chimeric antigen receptor (CAR) T cell therapy has been used as a targeted approach in cancer therapy. Relapsed and refractory acute leukemia in pediatrics has been difficult to treat with conventional therapy due to dose-limiting toxicities. With the recent success of CD 19 CAR in pediatric patients with B cell acute lymphoblastic leukemia (ALL), this mode of therapy has become a very attractive option for these patients with high-risk disease. In this review, we will discuss current treatment paradigms of pediatric acute leukemia and potential therapeutic targets for additional high-risk populations, including T cell ALL, AML, and infant ALL.