Characteristics and outcomes of acute myelogenous leukemia patients with very late relapse (>5 years)

Late relapse after hematopoietic stem cell transplantation for acute leukemia: a retrospective study by SFGM-TC

Late relapse (LR) after allogeneic hematopoietic stem cell transplantation (AHSCT) for acute leukemia is a rare event (nearly 4.5%) and raises the questions of prognosis and outcome after salvage therapy. We performed a retrospective multicentric study between January 1, 2010, and December 31, 2016, using data from the French national retrospective register ProMISe provided by the SFGM-TC (French Society for Bone Marrow Transplantation and Cellular Therapy). We included patients presenting with LR, defined as a relapse occurring at least 2 years after AHSCT. We used the Cox model to identify prognosis factors associated with LR. During the study period, a total of 7582 AHSCTs were performed in 29 centers, and 33.8% of patients relapsed. Among them, 319 (12.4%) were considered to have LR, representing an incidence of 4.2% for the entire cohort. The full dataset was available for 290 patients, including 250 (86.2%) with acute myeloid leukemia and 40 (13.8%) with acute lymphoid leukemia. The median interval from AHSCT to LR was 38.2 months (interquartile range [IQR], 29.2 to 49.7 months), and 27.2% of the patients had extramedullary involvement at LR (17.2% exclusively and 10% associated with medullary involvement). One-third of the patients had persistent full donor chimerism at LR. Median overall survival (OS) after LR was 19.9 months (IQR, 5.6 to 46.4 months). The most common salvage therapy was induction regimen (55.5%), with complete remission (CR) obtained in 50.7% of cases. Ninety-four patients (38.5%) underwent a second AHSCT, with a median OS of 20.4 months (IQR, 7.1 to 49.1 months). Nonrelapse mortality after second AHSCT was 18.2%. The Cox model identified the following factors as associated with delay of LR: disease status not in first CR at first HSCT (odds ratio [OR], 1.31; 95% confidence interval [CI], 1.04 to 1.64; P = .02) and the use of post-transplantation cyclophosphamide (OR, 2.23; 95% CI, 1.21 to 4.14; P = .01). Chronic GVHD appeared to be a protective factor (OR, .64; 95% CI, .42 to .96; P = .04). The prognosis of LR is better than in early relapse, with a median OS after LR of 19.9 months. Salvage therapy associated with a second AHSCT improves outcome and is feasible, without creating excess toxicity.

Cost-Effectiveness Analysis of Venetoclax in Combination with Azacitidine Versus Azacitidine Monotherapy in Patients with Acute Myeloid Leukemia Who are Ineligible for Intensive Chemotherapy: From a US Third Party Payer Perspective

OBJECTIVES

Using individual patient-level data from the phase 3 VIALE-A trial, this study assessed the cost-effectiveness of venetoclax in combination with azacitidine compared with azacitidine monotherapy for patients newly diagnosed with acute myeloid leukemia (AML) who are ineligible for intensive chemotherapy, from a United States (US) third-party payer perspective.

METHODS

A partitioned survival model with a 28-day cycle and three health states (event-free survival (EFS), progressive/relapsed disease, and death) was developed to estimate costs and effectiveness of venetoclax + azacitidine versus azacitidine over a lifetime (25-year) horizon. Efficacy inputs (overall survival (OS), EFS, and complete remission (CR)/CR with incomplete marrow recovery (CRi) rate) were estimated using VIALE-A data. Best-fit parametric models per Akaike Information Criterion were used to extrapolate OS until reaching EFS and extrapolate EFS until Year 5. Within EFS, the time spent in CR/CRi was estimated by applying the CR/CRi rate to the EFS curve. Past Year 5, patients still in EFS were considered cured and to have the same mortality as the US general population. Mean time on treatment (ToT) for both regimens was based on the time observed in VIALE-A. Costs of drug acquisition, drug administration (initial and subsequent treatments), subsequent stem cell transplant procedures, adverse events (AEs), and healthcare resource utilization (HRU) associated with health states were obtained from the literature/public data and inflated to 2021 US dollars. Health state utilities were estimated using EuroQol-5 dimension-5 level data from VIALE-A; AE disutilities were obtained from the literature. Incremental cost-effectiveness ratios (ICERs) per life-year (LY) and quality-adjusted life-year (QALY) gained were estimated. Deterministic sensitivity analyses (DSA), scenario analyses, and probabilistic sensitivity analyses (PSA) were also performed.

RESULTS

Over a lifetime horizon, venetoclax + azacitidine versus azacitidine led to gains of 1.89 LYs (2.99 vs. 1.10, respectively) and 1.45 QALYs (2.30 vs. 0.84, respectively). Patients receiving venetoclax + azacitidine incurred higher total lifetime costs ($250,486 vs. $110,034 (azacitidine)). The ICERs for venetoclax + azacitidine versus azacitidine were estimated at $74,141 per LY and $96,579 per QALY gained. Results from the DSA and scenario analyses supported the base-case findings, with ICERs ranging from $60,718 to $138,554 per QALY gained. The results were most sensitive to varying the parameters for the venetoclax + azacitidine base-case EFS parametric function (Gompertz), followed by alternative approaches for ToT estimation, treatment costs of venetoclax + azacitidine, standard mortality rate value and ToT estimation, alternative sources to inform HRU, different cure modeling assumptions, and the parameters for the venetoclax + azacitidine base-case OS parametric function (log-normal). Results from the PSA showed that, compared with azacitidine, venetoclax + azacitidine was cost-effective in 99.9% of cases at a willingness-to-pay threshold of $150,000 per QALY.

CONCLUSIONS

This analysis suggests that venetoclax + azacitidine offers a cost-effective strategy in the treatment of patients with newly diagnosed AML who are ineligible for intensive chemotherapy from a US third-party payer perspective.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT02993523. Date of registration: 15 December 2016.

Outcomes of Patients With Acute Myeloid Leukemia Who Relapse After 5 Years of Complete Remission

Leukemia relapse 5 years after achieving first complete remission (CR1) is uncommon in patients with acute myeloid leukemia (AML). In this study, we evaluated the outcomes of AML patients with late relapse at our institution and reviewed the literature for these patients. The study cohort consisted of nine AML patients with late relapse. The median interval between CR1 and AML relapse was 6.1 years (range: 5.1–16.2 years). At relapse, the karyotype was different from the initial AML diagnosis in 50% of patients. At the time of AML relapse, seven patients received induction chemotherapy and two patients received hypomethylating agents with an overall CR rate of 66%. The median time to relapse after achieving second CR (CR2) was 16.5 months [95% confidence interval (CI): 9.4, NA]. The median overall survival after first relapse was 28.6 months (95% CI: 7.3, 3.4–66.5 months). Despite initial CR after reinduction therapy, relapse rates are still high, suggesting that alternative strategies for postremission therapies are warranted in CR2. These approaches include the use of allogeneic hematogenic cell transplantation and the use of newly approved AML agents as maintenance therapy in nontransplant eligible patients.

Very Late Relapse in Pediatric Acute Myeloid Leukemia: A Case Report and Brief Literature Review

Acute myeloid leukemia (AML) is a heterogenous group of diseases affecting ~500 children in the United States annually. With current therapy, 90% of these children will obtain complete remission. However, 30% to 40% of these patients will relapse, most commonly within the first 3 years. Very late relapses, defined as relapse occurring >5 years after complete remission, are rare, accounting for 1% to 3% of relapses. We describe a patient with AML harboring an AFDN/KMT2A translocation who relapsed 12 years after matched sibling stem cell transplant, provide a brief review of the relevant literature, and describe proposed mechanisms to explain very late relapse AML.

Genomic characterization of relapsed acute myeloid leukemia reveals novel putative therapeutic targets

Relapse is the leading cause of death of adult and pediatric patients with acute myeloid leukemia (AML). Numerous studies have helped to elucidate the complex mutational landscape at diagnosis of AML, leading to improved risk stratification and new therapeutic options. However, multi-whole-genome studies of adult and pediatric AML at relapse are necessary for further advances. To this end, we performed whole-genome and whole-exome sequencing analyses of longitudinal diagnosis, relapse, and/or primary resistant specimens from 48 adult and 25 pediatric patients with AML. We identified mutations recurrently gained at relapse in ARID1A and CSF1R, both of which represent potentially actionable therapeutic alternatives. Further, we report specific differences in the mutational spectrum between adult vs pediatric relapsed AML, with MGA and H3F3A p.Lys28Met mutations recurrently found at relapse in adults, whereas internal tandem duplications in UBTF were identified solely in children. Finally, our study revealed recurrent mutations in IKZF1, KANSL1, and NIPBL at relapse. All of the mentioned genes have either never been reported at diagnosis in de novo AML or have been reported at low frequency, suggesting important roles for these alterations predominantly in disease progression and/or resistance to therapy. Our findings shed further light on the complexity of relapsed AML and identified previously unappreciated alterations that may lead to improved outcomes through personalized medicine.

Proteome and Phosphoproteome Changes Associated with Prognosis in Acute Myeloid Leukemia

Acute myeloid leukemia (AML) is a hematological cancer that mainly affects the elderly. Although complete remission (CR) is achieved for the majority of the patients after induction and consolidation therapies, nearly two-thirds relapse within a short interval. Understanding biological factors that determine relapse has become of major clinical interest in AML. We utilized liquid chromatography tandem mass spectrometry (LC-MS/MS) to identify the protein changes and protein phosphorylation events associated with AML relapse in primary cells from 41 AML patients at time of diagnosis. Patients were defined as relapse-free if they had not relapsed within a five-year clinical follow-up after AML diagnosis. Relapse was associated with increased expression of RNA processing proteins and decreased expression of V-ATPase proteins. We also observed an increase in phosphorylation events catalyzed by cyclin-dependent kinases (CDKs) and casein kinase 2 (CSK2). The biological relevance of the proteome findings was supported by cell proliferation assays using inhibitors of V-ATPase (bafilomycin), CSK2 (CX-4945), CDK4/6 (abemaciclib) and CDK2/7/9 (SNS-032). While bafilomycin preferentially inhibited the cells from relapse patients, the kinase inhibitors were less efficient in these cells. This suggests that therapy against the upregulated kinases could also target the factors inducing their upregulation rather than their activity. This study, therefore, presents markers that could help predict AML relapse and direct therapeutic strategies.

Late relapse in acute myeloid leukemia (AML): clonal evolution or therapy-related leukemia?

Late relapse, defined as relapse arising after at least 5 years of remission, is rare and occurs in 1–3% of patients with acute myeloid leukemia (AML). The underlying mechanisms of late relapse remain poorly understood. We identified patients with AML who achieved remission with standard induction chemotherapy and relapsed after at least five years of remission (n = 15). Whole exome sequencing was performed in available bone marrow samples obtained at diagnosis (n = 10), remission (n = 6), and first relapse (n = 10). A total of 41 driver mutations were identified, of which 11 were primary tumor-specific, 17 relapse-specific, and 13 shared (detected both in primary and relapsed tumor samples). We demonstrated that 12 of 13 shared mutations were in epigenetic modifier and spliceosome genes. Longitudinal genomic characterization revealed that in eight of 10 patients the founder leukemic clone persisted after chemotherapy and established the basis of relapse years later. Understanding the mechanisms of such quiescence in leukemic cells may help designing future strategies aimed at increasing remission duration in patients with AML.

Very Late Relapse of Acute Promyelocytic Leukemia 17 Years after Continuous Remission

The prognosis of acute promyelocytic leukemia (APL) has been improved by the combination of all-trans retinoic acid (ATRA) with chemotherapy. Nonetheless, relapse occurs in a certain proportion of patients, mostly within three to four years after treatment. We herein report a patient treated with ATRA and chemotherapy achieving remission who relapsed approximately 17 years after the treatment. A literature review identified 5 additional reported cases of APL relapse after more than 10 years. None of them presented with generally established risk factors for relapse, such as a high leukocyte count. The potential for late relapse of APL occurring more than 10 years after treatment should be recognized.

Younger adults with acute myeloid leukemia in remission for ≥ 3 years have a high likelihood of cure: The ECOG experience in over 1200 patients

We examined 1229 younger patients with acute myeloid leukemia who achieved CR1 on Eastern Cooperative Oncology Group trials. We defined late relapse as occurring after ≥ 3 years of CR1. With median follow-up of 11.3 years, there were 14 late relapses (1.1% of CR1 patients; 3.3% of 3-year CR1 patients). Eight achieved second CR and median overall survival after late relapse was 3.2 years. Most patients tested (9/11) had a normal karyotype at diagnosis; none had new cytogenetic abnormalities at relapse. Late relapse is rare and nearly all 3-year CR1 patients are cured. If late relapse occurs, outcomes are relatively favorable.

Long-term medical costs and life expectancy of acute myeloid leukemia: a probabilistic decision model

BACKGROUND

Acute myeloid leukemia (AML) can be diagnosed at any age and treatment, which can be given with supportive and/or curative intent, is considered expensive compared with that for other cancers. Despite this, no long-term predictive models have been developed for AML, mainly because of the complexities associated with this disease.

OBJECTIVE

The objective of the current study was to develop a model (based on a UK cohort) to predict cost and life expectancy at a population level.

METHODS

The model developed in this study combined a decision tree with several Markov models to reflect the complexity of the prognostic factors and treatments of AML. The model was simulated with a cycle length of 1 month for a time period of 5 years and further simulated until age 100 years or death. Results were compared for two age groups and five different initial treatment intents and responses. Transition probabilities, life expectancies, and costs were derived from a UK population-based specialist registry-the Haematological Malignancy Research Network (www.hmrn.org).

RESULTS

Overall, expected 5-year medical costs and life expectancy ranged from £8,170 to £81,636 and 3.03 to 34.74 months, respectively. The economic and health outcomes varied with initial treatment intent, age at diagnosis, trial participation, and study time horizon. The model was validated by using face, internal, and external validation methods. The results show that the model captured more than 90% of the empirical costs, and it demonstrated good fit with the empirical overall survival.

CONCLUSIONS

Costs and life expectancy of AML varied with patient characteristics and initial treatment intent. The robust AML model developed in this study could be used to evaluate new diagnostic tools/treatments, as well as enable policy makers to make informed decisions.

Very late isolated CNS relapse of acute myeloid leukemia

Isolated central nervous system (CNS) relapse in acute myeloid leukemia (AML) rarely occurs later than 2 years after remission. We present a child diagnosed with AML (FAB M5) without CNS involvement at diagnosis who was treated with chemotherapy and consolidated with autologous hematopoietic stem cell transplantation. He was in complete remission for >6 years until he had an isolated CNS relapse. He was treated with only intrathecal chemotherapy and achieved a second complete remission, but relapsed in the bone marrow 5 months after the CNS relapse. Treatment of late isolated CNS relapse of AML is discussed.

Management of AML: who do we really cure?

Most clinicians caring for patients with AML do not use the word "cure" casually, since for many patients diagnosed with AML, a state of cure or even of long term survival remains elusive. Analysis of prognostic factors may aid in defining the chance for cure in various AML subtypes, and improvements are required at all stages of AML treatment if cure is to be realized in a higher proportion of patients. In order to improve outcome, requirements will include targeting the mutation responsible for the leukemia emergence, suppressing the stem or progenitor cell which acquires the mutation, and the capability to deliver therapy to patients who themselves have adverse co-morbidities.

Very late recurrences of leukemia: why does leukemia awake after many years of dormancy?

We report a heterogeneous group of very late recurrences of leukemia occurring more than 10 years after initial treatment including 2 cases of childhood acute lymphoblastic leukemia (ALL) which recurred after more than 20 years of remission, 2 cases of donor cell leukemia which developed more than 10 years after allograft for acute myeloid leukemia (AML) and high risk myelodysplastic syndrome (MDS) and 2 cases of chronic myeloid leukemia (CML) relapsing 13 and 17 years after allograft. Case descriptions are followed by a discussion regarding possible mechanisms leading to leukemia recurrence and a review of the literature.

Late relapses in acute myeloid leukemia: analysis of characteristics and outcome

Relapse after 5 years of complete remission (CR) is uncommon in acute myeloid leukemia (AML). Among 2347 patients seen between 1980 and 2008, 1366 achieved CR; 942 relapsed. Eleven (1.16% of all relapses) relapsed after a CR of >5 years. The median age was 66 years (range, 37-79). Initial therapy was cytarabine plus anthracycline in six, amsacrine-based in three, and other in two. The median CR1 duration was 81 months (range, 60-137). At relapse, the karyotype was different from the initial finding in five of eight (63%) patients with available data. Treatment for relapse included cytarabine with anthracycline in eight, and other in three patients, with a second CR (CR2) achieved in four (36%). The median CR2 duration was 1 month (range, 0-37), and median survival after relapse was 6.4 months (range, 1-39). Late relapses in AML are infrequent, with poor response to therapy. Karyotype at relapse is frequently different, raising the question of second AML versus relapse with the original clone.