Treatment of therapy-related myeloid neoplasms with high-dose cytarabine/mitoxantrone followed by hematopoietic stem cell transplant

Adult rhabdomyosarcoma combined with acute myeloid leukemia: A case report

BACKGROUND

Rhabdomyosarcoma is a tumor of mesenchymal origin. Secondary leukemia is a complication of previous transformation to other hematologic disorders or is a treatment-related acute myeloid leukemia secondary to cytotoxic chemotherapy or radiation therapy for other malignancies.

CASE SUMMARY

We present the case of a 36-year-old female patient who was diagnosed with rhabdomyosarcoma and acute myeloid leukemia. Further disease progression was observed after multiline chemotherapy. Eventually, the patient suffered cerebral hemorrhage, which resulted in death.

CONCLUSION

The incidence of rhabdomyosarcoma in adults is extremely low, and secondary leukemia caused by rhabdomyosarcoma is even rarer. Secondary leukemia has a very poor prognosis and a low overall survival rate.

A phase 1 study of azacitidine with high-dose cytarabine and mitoxantrone in high-risk acute myeloid leukemia

In this phase 1 study, azacitidine (AZA) was given before high-dose cytarabine (HiDAC) and mitoxantrone (mito) based on the hypothesis that epigenetic priming with a hypomethylating agent before cytotoxic chemotherapy would improve response rates in patients with high-risk acute myeloid leukemia (AML), including relapsed/refractory disease. The primary objective was to establish the recommended phase 2 dose of AZA given before standard HiDAC/mito. In a dose escalation scheme, 46 patients (median age, 66 years) received AZA at 37.5, 50, or 75 mg/m2 subcutaneously or IV once daily on days 1 to 5 followed by HiDAC (3000 mg/m2) and mitoxantrone (30 mg/m2) once each on days 6 and 10 (the HiDAC/mito dose was reduced 33% in elderly subjects). Two dose-limiting toxicities occurred (both in the same patient): acute liver failure and kidney injury at the 50 mg/m2 dose. The 30-day induction death rate was 2.2% (1 of 46). The overall response rate, including complete remission and complete remission with incomplete count recovery, was 61% (28 of 46). Previously untreated patients aged ≥60 years with therapy-related AML and de novo AML were more likely to respond than untreated patients with AML progressing from an antecedent hematologic disorder (myelodysplastic syndrome and chronic myelomonocytic leukemia). Patients with favorable European Leukemia Network risk (P = .008), NPM1 mutations (P = .007), or IDH2 mutations (P = .03) were more likely to respond, and those with TP53 mutations (P = .03) were less likely to respond. The recommended phase 2 dose of AZA is 75 mg/m2 per day on days 1 to 5 followed by HiDAC (3000 mg/m2) and mitoxantrone (30 mg/m2) once each on days 6 and 10. This trial was registered at www.clinicaltrials.gov as #NCT01839240.

Genetic Pathway in the Pathogenesis of Therapy-Related Myeloid Neoplasms: A Literature Review

Therapy-related myeloid neoplasms are a life-threatening and often fatal complication, associated with poor prognosis outcomes and with high-risk unfavorable cytogenetic abnormalities including complex karyotype. They occur after the treatment of primary malignancies using chemotherapy and/or radiation therapy. Such therapy is not specific to cancer cells, and also damages the deoxyribonucleic acid (DNA) of normal cells, resulting in unbalanced and balanced translocations. There are eight genetic pathways, whose details are summarized in this review, depending on the cytogenetic abnormalities induced. This abnormality is the major contributor to the development of therapy-related myeloid neoplasms. The etiology of these neoplasms depends on the complex interaction between the nature and dose of the cytotoxic agent, the environment, and the presence of subsequent inherited mutations. This review aims to elaborate upon recent knowledge regarding the etiology, pathogenesis, and genetic pathways of therapy-related myeloid neoplasms. A deeper understanding of their etiology would aid physicians in more careful monitoring of patients during or after cytotoxic therapy for hematological malignancy. Ultimately, this knowledge could influence initial treatment strategies, with the aim of reducing both the incidence and serious complications of neoplasms. Therefore, early detection of DNA lesions is vital. The authors recommend that primary malignancy be treated with targeted therapy.

The leukemia strikes back: a review of pathogenesis and treatment of secondary AML

Secondary AML is associated with a disproportionately poor prognosis, consistently shown to exhibit inferior response rates, event-free survival, and overall survival in comparison with de novo AML. Secondary AML may arise from the evolution of an antecedent hematologic disorder, or it may arise as a complication of prior cytotoxic chemotherapy or radiation therapy in the case of therapy-related AML. Because of the high frequency of poor-risk cytogenetics and high-risk molecular features, such as alterations in TP53, leukemic clones are often inherently chemoresistant. Standard of care induction had long remained conventional 7 + 3 until its reformulation as CPX-351, recently FDA approved specifically for secondary AML. However, recent data also suggests relatively favorable outcomes with regimens based on high-dose cytarabine or hypomethylating agents. With several investigational agents being studied, the therapeutic landscape becomes even more complex, and the treatment approach involves patient-specific, disease-specific, and therapy-specific considerations.

Better treatment outcomes in patients with actively treated therapy-related myeloid neoplasms harboring a normal karyotype

We analyzed treatment outcomes and prognostic factors in adult patients with therapy-related myeloid neoplasms (t-MNs) to select patients who would be benefited by active anticancer treatment. After excluding 18 patients who received palliative care only and 13 patients with acute promyelocytic leukemia, 72 t-MN patients (45 with acute myeloid leukemia and 27 with myelodysplastic syndrome) were retrospectively evaluated. Among them, 10 (13.9%), 32 (44.4%), and 30 patients (41.7%) had favorable, intermediate- and adverse-risk cytogenetics, respectively. Among patients with intermediate-risk cytogenetics, patients with a normal karyotype (NK; N = 20) showed superior allogeneic stem cell transplantation-censored overall survival (AC-OS) and OS compared to those with non-NK-intermediate-risk cytogenetics (P < 0.001). In the multivariate analysis, male sex, age ≥ 70 years, and unfavorable cytogenetics (non-NK-intermediate plus adverse risk cytogenetics) were associated with inferior AC-OS. Those results suggest that a more-refined subdivision of risk stratification would be necessary in patients with intermediate-risk cytogenetics.

How I treat the blast phase of Philadelphia chromosome–negative myeloproliferative neoplasms

The classic Philadelphia chromosome (Ph)–negative myeloproliferative neoplasms (MPNs) are a heterogeneous group of hematopoietic stem-cell diseases, characterized by activated JAK/STAT signaling and significant phenotypic mimicry, including a propensity for evolution to myeloid blast phase disease. Effective therapeutic options are limited for patients with Ph− MPNs in the blast phase (MPN-BP), and allogeneic stem-cell transplantation is the only known cure. Our increasing understanding of the molecular pathogenesis of this group of diseases, coupled with the increasing availability of targeted agents, has the potential to inform new subset-specific therapeutic approaches. Ultimately, progress in MPN-BP will hinge on prospective clinical and translational investigations with the goal of generating more effective treatment interventions. This case-based review highlights the molecular and clinical heterogeneities of MPN-BP and incorporates a treatment algorithm that underscores the importance of a personalized approach to this challenging group of diseases.

A phase I study of selinexor in combination with high-dose cytarabine and mitoxantrone for remission induction in patients with acute myeloid leukemia

BACKGROUND

Novel therapies for patients with acute myeloid leukemia (AML) are imperative, particularly for those with high-risk features. Selinexor, an exportin 1 (XPO1/CRM1) inhibitor, has demonstrated anti-leukemia activity as a single agent, as well as in combination with anthracyclines and/or DNA-damaging agents.

METHODS

We report the findings of a phase I dose escalation trial with cohort expansion in 20 patients with newly diagnosed or relapsed/refractory AML that combined selinexor with age-adjusted high-dose cytarabine and mitoxantrone (HiDAC/Mito).

RESULTS

Three (15%) patients received the initial dose of 60 mg of selinexor (~ 35 mg/m2), and 17 (85%) received the target level of 80 mg (~ 50 mg/m2). No dose-limiting toxicities were observed. Common adverse events included febrile neutropenia (70%), diarrhea (40%), anorexia (30%), electrolyte abnormalities (30%), bacteremia (25%), cardiac toxicities (25%), fatigue (25%), and nausea/vomiting (25%). None were unexpected given the HiDAC/Mito regimen. Serious adverse events occurred in 6 (30%) patients; one was fatal. Ten (50%) patients achieved a complete remission (CR), 3 (15%) achieved CR with incomplete recovery (CRi), 1 (5%) achieved partial remission (PR), and 6 (30%) had progressive disease for an overall response rate (ORR) of 70%. Eight of 14 (57%) responders proceeded to allogeneic stem cell transplantation. Correlative studies of WT1 levels showed persistently detectable levels in patients who either did not respond or relapsed quickly after induction.

CONCLUSION

The selinexor/HiDAC/Mito regimen is feasible and tolerable at selinexor doses of 80 mg/day (~ 50 mg/m2/day) twice weekly. The recommended phase II dose is 80 mg and warrants further study in this combination.

TRIAL REGISTRATION

ClinicalTrials.gov , NCT02573363 . Registered October 5, 2015.

Therapy-related myeloid neoplasms - what have we learned so far?

Therapy-related myeloid neoplasms are neoplastic processes arising as a result of chemotherapy, radiation therapy, or a combination of these modalities given for a primary condition. The disease biology varies based on the etiology and treatment modalities patients receive for their primary condition. Topoisomerase II inhibitor therapy results in balanced translocations. Alkylating agents, characteristically, give rise to more complex karyotypes and mutations in p53. Other etiologies include radiation therapy, high-dose chemotherapy with autologous stem cell transplantation and telomere dysfunction. Poor-risk cytogenetic abnormalities are more prevalent than they are in de novo leukemias and the prognosis of these patients is uniformly dismal. Outcome varies according to cytogenetic risk group. Treatment recommendations should be based on performance status and karyotype. An in-depth understanding of risk factors that lead to the development of therapy-related myeloid neoplasms would help developing risk-adapted treatment protocols and monitoring patients after treatment for the primary condition, translating into reduced incidence, early detection and timely treatment.

Recent advances in the management of therapy-related myelodysplastic syndromes and acute myeloid leukemia

PURPOSE OF REVIEW

Therapy-related myelodysplastic syndromes and acute myelogenous leukemia (t-MDS/AML) comprise an increasingly common, poor-risk disease cohort without standard treatment options. This review describes available treatments and recent advances that may influence the clinical management of t-MDS/AML.

RECENT FINDINGS

Multiple retrospective studies have identified poor-risk cytogenetics, chemotherapy resistance, comorbidities from prior cancer and therapy, and persistence of the primary malignancy as factors that contribute to poor clinical outcomes of t-MDS/AML. Recent analyses show that t-MDS/AML can respond to standard therapy, but responses are less durable. In most cases, cure is made more likely with allogeneic stem cell transplantation. These findings suggest that improved survival may result from earlier, low-intensity nontransplant therapy, and aggressive pursuit of reduced-intensity transplant approaches in eligible individuals coupled with posttransplant relapse prevention strategies. Molecular characterization of t-MDS/AML may aid future clinical management decisions and identify targets for therapy.

SUMMARY

Data emerging from recent t-MDS/AML studies are shedding light on factors that contribute to disease biology and poor clinical outcomes. These findings can be used to develop strategies to improve the treatment and survival of patients with t-MDS/AML.

Therapy-related myeloid neoplasms: pathobiology and clinical characteristics

Therapy-related myeloid neoplasms (t-MNs) are serious long-term consequences of cytotoxic treatments for an antecedent disorder. t-MNs are observed after ionizing radiation as well as conventional chemotherapy including alkylating agents, topoisomerase-II-inhibitors and antimetabolites. In addition, adjuvant use of recombinant human granulocyte-colony stimulating factor may also increase the risk of t-MNs. There is clinical and biological overlap between t-MNs and high-risk de novo myelodysplastic syndromes and acute myeloid leukaemia suggesting similar mechanisms of leukaemogenesis. Human studies and animal models point to a prominent role of genetic susceptibilty in the pathogenesis of t-MNs. Common genetic variants have been identified that modulate t-MN risk, and t-MNs have been observed in some cancer predisposition syndromes. In either case, establishing a leukaemic phenotype requires acquisition of somatic mutations - most likely induced by the cytotoxic treatment. Knowledge of the specific nature of the initiating exposure has allowed the identification of crucial pathogenetic mechanisms and for these to be modelled in vitro and in vivo. Prognosis of patients with t-MNs is dismal and at present, the only curative approach for the majority of these individuals is haematopoietic stem cell transplantation, which is characterized by high transplant-related mortality rates. Novel transplantation strategies using reduced intensity conditioning regimens as well as novel drugs - demethylating agents and targeted therapies - await clinical testing and may improve outcome. Ultimately, individual assessment of genetic risk factors may translate into tailored therapies and establish a strategy for reducing t-MN incidences without jeopardizing therapeutic success rates for the primary disorders.