Characterisation of extramedullary relapse in patients with chronic myeloid leukemia in advanced disease after allogeneic stem cell transplantation

Correlation analysis of bone marrow microvessel density and miRNA expression on drug resistance in patients with chronic myelogenous leukemia after tyrosine kinase inhibitor treatment

OBJECTIVE

This study analyzed the relationship between bone marrow microvessel density (MVD) and the expression of four miRNAs with chronic myelogenous leukemia (CML) resistance after tyrosine kinase inhibitor (TKI) treatment.

METHODS

234 CML patients were divided into resistance and non-resistance groups in terms of the results of the 5-year follow-up. Patients were divided into the Optimum response group and the Warning/Failure group based on TKI response. MVD was determined by immunohistochemistry, and the expression levels of four miRNAs (miR-106a, miR-155, miR-146a, and miR-340) in bone marrow biopsy specimens were examined by qPCR. We evaluated the association of MVD with four miRNAs and them predictive value for CML resistance after TKI treatment.

RESULTS

The MVD and the levels of miR-106a, miR-155, and miR-146a were significantly higher while the miR-340 level was lower in the resistance group than the non-resistance group. Besides, MVD had a significant correlation with the levels of miR-340 and miR-155. According to the results of survival analysis, MVD as well as miR-340 and miR-155 levels were observably correlated with 5-year survival of patients without TKI resistance. The results of the ROC curve indicated that the MVD, miR-106a, miR-340, and miR-155 had good predictive accuracy for CML resistance after TKI treatment. As for the results of multivariate analysis, disease stage, risk level (high risk), high MVD, low miR-340 expression, and high miR-155 expression were all independent risk factors for CML resistance.

CONCLUSION

MVD and the expression of miR-340 and miR-155 are closely associated with CML resistance after TKI treatment.

Post-transplant leukemia relapse in organs: biology. and behavior in 585 reports

Resistance of extramedullary leukemia growth post-transplant prevents cure. Review of its behavior detailed in 585 published cases should lead to better treatment. Leukemic tumors were found up to 13 years after transplant, most in sites inaccessible to physical exam. In 83%, marrow was not in morphologic relapse; next relapse was most often extramedullary. Induction protocols alone produced few durable responses in acute leukemias and fatal marrow aplasia in 17 %. Overall, 120 patients survived over 2 years, 43 relapse-free up to 18 years, the majority after combined tumor-directed and systemic therapy. Overall median survival was 9 months. This review highlights how results can improve: by defining extent of leukemia involvement with scans before transplant, and emergently when leukemic tumor is found after, ablating tumor directly to abort metastasis, and determining dosing of systemic chemotherapy that protects, without ablating, donor marrow. Monitoring total body remission with body scans should increase transplant cures.

Population pharmacokinetic approach for evaluation of treosulfan and its active monoepoxide disposition in plasma and brain on the basis of a rat model

PURPOSE

Efficacy of treosulfan, used in the treatment of marrow disorders, depends on the activity of its monoepoxy-(EBDM) and diepoxy compounds. The study aimed to describe the pharmacokinetics of treosulfan and EBDM in the rat plasma and brain by means of mixed-effects modelling.

METHODS

The study had a one-animal-per-sample design and included ninty-six 10-week-old Wistar rats of both sexes. Treosulfan and EBDM concentrations in the brain and plasma were measured by an HPLC-MS/MS method. The population pharmacokinetic model was established in NONMEM software with a first-order estimation method with interaction.

RESULTS

One-compartment pharmacokinetic model best described changes in the concentrations of treosulfan in plasma, and EBDM concentrations in plasma and in the brain. Treosulfan concentrations in the brain followed a two-compartment model. Both treosulfan and EBDM poorly penetrated the blood-brain barrier (ratio of influx and efflux clearances through the blood-brain barrier was 0.120 and 0.317 for treosulfan and EBDM, respectively). Treosulfan plasma clearance was significantly lower in male rats than in females (0.273 L/h/kg vs 0.419 L/h/kg).

CONCLUSIONS

The developed population pharmacokinetic model is the first that allows the prediction of treosulfan and EBDM concentrations in rat plasma and brain. These results provide directions for future studies on treosulfan regarding the contribution of transport proteins or the development of a physiological-based model.

Extramedullary relapse of leukemia after allogeneic hematopoietic stem cell transplantation: A retrospective study

Extramedullary relapse (EMR) rarely occurs after allogeneic hematopoietic stem cell transplantation (HSCT) in leukemia. This study was to investigate the clinical characteristics of EMR.We retrospectively investigated 316 consecutive patients undergoing HSCT for acute leukemia or chronic myeloid leukemia (CML) at 2 institutions between January 2012 and February 2017. Furthermore, we analyzed and compared the risk factors and outcomes between EMR and bone marrow relapse (BMR).The 5-year cumulative incidence of EMR was 14.1%. The EMR incidence in acute myeloid leukemia, lymphoblastic leukemia, and CML was 17.5%, 18.9%, and 5.3%, respectively. CML had a lower EMR incidence rate. Compared to the BMR group, the EMR group had a longer median relapse-free time (10.5 months vs 5 months, P = .02), and the EMR group had a higher incidence rate of chronic graft-versus-host disease (50.0% vs 20.9%, P = .009). EMR had better estimated 3-year survival rates post-HSCT, and post-relapse, than did BMR (39.5% vs 9.5%, P < .001, and 21.9% vs 10.8%, P = .001). Multivariate analysis identified that adverse cytogenetics (hazard ratio [HR] = 9.034, P < .001) and extramedullary leukemia before HSCT (HR = 2.685, P = .027) were the independent risk factors for EMR after HSCT. In the EMR group, patients who achieved complete remission (CR) had a significantly better, estimated 3-year survival than did patients who did not achieve CR (38.4% vs 14.3%, P = .014).EMR is a significant contributor to mortality after HSCT, which appears to be resistant to most of the current therapies. Establishing effective strategies for EMR is important in improving outcomes after HSCT.

Extramedullary Relapse in a CML Patient after Allogeneic Stem Cell Transplantation

Myeloid or granulocytic sarcoma (GS) is a tumoral lesion consisting of immature granulocytic cells. It is a rare entity during the course of CML patients especially after allogeneic stem cell transplantation (SCT). Relapse without bone marrow involvement is much rarer. We report a case of CML patient who relapsed with isolated granulocytic sarcoma after allogeneic SCT during cytogenetic and molecular remission. 28-year-old male was diagnosed as CML and allogeneic SCT was performed because of refractory disease to tyrosine kinase inhibitors. Complete cytogenetic and molecular response was achieved after allogeneic SCT followed by dasatinib treatment. Approximately 5 years after the transplantation, very rapidly progressive lesion was documented and diagnosed as GS although he was at molecular and cytogenetic remission. The patient died during chemotherapy due to sepsis. GS relapse after allogeneic SCT is a very rare type of relapse in CML patients with molecular and cytogenetic remission. Since it is a very aggressive disease with a poor prognosis, combined chemoradiotherapies with other possible options like DLI or second allogeneic SCT should be considered as soon as the diagnosis is confirmed.

Ph-negative isolated myeloid sarcoma with NPM1 gene mutation in adolescent with Ph-positive chronic myeloid leukemia in remission after treatment with allogeneic bone marrow transplantation and imatinib mesylate

Few patients in remission of Ph-positive chronic myelogenous leukemia (CML) develop Ph-negative MDS/AML, usually with clonal cytogenetic abnormalities. Isolated Ph-negative myeloid sarcoma (MS) is presented here as a form of such disorder, different from Ph-positive MS establishing CML relapse in blastic phase. We describe 11-year-old male who developed Ph-negative isolated MS with NPM1 mutation, remaining in complete molecular remission of Ph-positive chronic myeloid leukemia treated with allo-HSCT in first chronic phase and with imatinib and donor lymphocyte infusion in molecular relapse. The possible mechanisms of the tumor formation are reviewed with stress on importance of comprehensive molecular/cytogenetic evaluations.

Relapse after allogeneic stem cell transplantation

Since allogeneic stem cell transplantation (SCT) represents an intensive curative treatment for high-risk malignancies, its failure to prevent relapse leaves few options for successful salvage treatment. While many patients have a high early mortality from relapse, some respond and have sustained remissions, and a minority has a second chance of cure with appropriate therapy. The prognosis for relapsed hematological malignancies after SCT depends on four factors: the time elapsed from SCT to relapse (with relapses occurring within 6 months having the worst prognosis), the disease type (with chronic leukemias and some lymphomas having a second possibility of cure with further treatment), the disease burden and site of relapse (with better treatment success if disease is treated early), and the conditions of the first transplant (with superior outcome for patients where there is an opportunity to increase either the alloimmune effect, the specificity of the antileukemia effect with targeted agents or the intensity of the conditioning in a second transplant). These features direct treatments toward either modified second transplants, chemotherapy, targeted antileukemia therapy, immunotherapy or palliative care.

Donor lymphocyte infusion following allogeneic hematopoietic stem cell transplantation

INTRODUCTION

Allogeneic hematopoietic stem cell transplantation (SCT) is the treatment of choice for many malignant hematological disorders. Following recent improvements in non-relapse-related mortality rates, relapse has become the commonest cause of treatment failure. Infusion of donor lymphocytes can potentially enhance immune-mediated antitumor activity and offers a salvage option for some patients. This paper reviews the current literature on the efficacy of this therapeutic strategy.

AREAS COVERED

The biology of adoptive cellular therapy with allogeneic immune cells to treat relapse across a spectrum of diseases in both the full intensity and reduced intensity hematopoietic SCT settings is explored. The review discusses the current limitations of the approach and reviews several new experimental strategies which aim to segregate the desired graft-versus-tumor effect from the deleterious effects of more widespread graft-versus-host reactivity.

EXPERT OPINION

Durable responses to DLI have been noted in chronic myeloid leukemia and responses have also been described in acute leukemia, multiple myeloma and chronic lymphoproliferative disorders. The new challenge in transplantation is to optimize DLI therapy in order to further improve patient outcomes.

Pleural/pericardic effusions during dasatinib treatment: incidence, management and risk factors associated to their development

IMPORTANCE OF THE FIELD

Despite the beneficial effect of imatinib treatment in chronic myeloid leukemia patients, some patients develop resistance and/or intolerance and need a switch to second-generation tyrosine kinase inhibitors. Dasatinib is indicated for chronic myeloid leukemia patients with resistance or intolerance to imatinib; it has 325-fold increase potency compared to imatinib and is active in mutated and unmutated resistant patients. Pleural/pericardic effusions are frequent complications during treatment with dasatinib, and usually are reported to require dose reduction or drug discontinuation. Changing the dasatinib regimen from 70 mg twice daily to 100 mg once daily reduces the risk of pleural effusions.

AREA COVERED IN THIS REVIEW

In this article, we review the incidence of the phenomenon observed in different dasatinib trials (Phase I - III) and the currently suggested management. We also describe the identified pathogenetic mechanisms related to the development and discuss the associated risk factors.

WHAT THE READER WILL GAIN

The aim of this paper is to provide healthcare professionals with clear guidance on the management of pleural effusions associated with dasatinib treatment. Recommendations are based on the published data and clinical experience from a number of different centers.

TAKE HOME MESSAGE

Literature evidences support the fact that with adequate management and monitoring of patients with predisposing factors, pleural effusions can be easily managed.

NCI First International Workshop on the Biology, Prevention, and Treatment of Relapse after Allogeneic Hematopoietic Stem Cell Transplantation: Report from the Committee on Treatment of Relapse after Allogeneic Hematopoietic Stem Cell Transplantation

Relapse is a major cause of treatment failure after allogeneic hematopoietic stem cell transplantation (alloHSCT). Treatment options for relapse have been inadequate, and the majority of patients ultimately die of their disease. There is no standard approach to treating relapse after alloHSCT. Withdrawal of immune suppression and donor lymphocyte infusions are commonly used for all diseases; although these interventions are remarkably effective for relapsed chronic myelogenous leukemia, they have limited efficacy in other hematologic malignancies. Conventional and novel chemotherapy, monoclonal antibody therapy, targeted therapies, and second transplants have been utilized in a variety of relapsed diseases, but reports on these therapies are generally anecdotal and retrospective. As such, there is an immediate need for well-designed, disease-specific trials for treatment of relapse after alloHSCT. This report summarizes current treatment options under investigation for relapse after alloHSCT in a disease-specific manner. In addition, recommendations are provided for specific areas of research necessary in the treatment of relapse after alloHSCT.