Allogeneic Hematopoietic Cell Transplantation for Patients with Mixed Phenotype Acute Leukemia.

Acute biphenotypic leukemias or mixed phenotype acute leukemias (MPAL) are rare and considered high risk. The optimal treatment and the role of allogeneic hematopoietic stem cell transplantation (alloHCT) are unclear. Most prior case series include only modest numbers of patients who underwent transplantation. We analyzed the outcome of 95 carefully characterized alloHCT patients with MPAL reported to the Center for International Blood and Marrow Transplant Research between 1996 and 2012. The median age was 20 years (range, 1 to 68). Among the 95 patients, 78 were in first complete remission (CR1) and 17 were in second complete remission (CR2). Three-year overall survival (OS) of 67% (95% confidence interval [CI], 57 to 76), leukemia-free survival of 56% (95% CI, 46 to 66), relapse incidence of 29% (95% CI, 20 to 38), and nonrelapse mortality of 15% (95% CI, 9 to 23) were encouraging. OS was best in younger patients (<20 years), but no significant differences were observed between those 20 to 40 years of age and those who were 40 years or older. A matched-pair analysis showed similar outcomes comparing MPAL cases to 375 acute myelogenous leukemia or 359 acute lymphoblastic leukemia cases. MPAL patients had more acute and a trend for more chronic graft-versus-host disease. No difference was observed between patients who underwent transplantation in CR1 versus those who underwent transplantation in CR2. AlloHCT is a promising treatment option for pediatric and adult patients with MPAL with encouraging long-term survival.

Broad genomic workup including optical genome mapping uncovers a DDX3X: MLLT10 gene fusion in acute myeloid leukemia.

In acute myeloid leukemia (AML), treatment decisions are currently made according to the risk classification of the European LeukemiaNet (ELN), which is based on genetic alterations. Recently, optical genome mapping (OGM) as a novel method proved to yield a genome-wide and detailed cytogenetic characterization at the time of diagnosis. A young female patient suffered from a rather unexpected aggressive disease course under FLT3 targeted therapy in combination with induction chemotherapy. By applying a "next-generation diagnostic workup" strategy with OGM and whole-exome sequencing (WES), a DDX3X: MLLT10 gene fusion could be detected, otherwise missed by routine diagnostics. Furthermore, several aspects of lineage ambiguity not shown by standard diagnostics were unraveled such as deletions of SUZ12 and ARPP21, as well as T-cell receptor recombination. In summary, the detection of this particular gene fusion DDX3X: MLLT10 in a female AML patient and the findings of lineage ambiguity are potential explanations for the aggressive course of disease. Our study demonstrates that OGM can yield novel clinically significant results, including additional information helpful in disease monitoring and disease biology.

Mixed phenotype acute leukemia with PML-RARα positive: a case report and literature review.

Mixed phenotype acute leukemia (MPAL) is an uncommon type of leukemia. It is one kind of malignant clonal diseases that expresses more than one genealogical specific antigen simultaneously. Most MPAL patients are associated with clonal chromosomal abnormalities and molecular genetic changes, such as t(9;22) (q34;q11) and KMT2A (MLL) rearrangement. These specific abnormalities usually have important guiding significance in MPAL diagnosis, targeted therapy and prognosis judgment. In this paper, we reported a case of MPAL, T/myeloid (M5) with an unfrequent combination of PML-RARα positivity and t(15;17). The treatment was successful with chemotherapy for both AML and ALL with daunorubicin, cytarabine (DA) and vincristine, prednisone (VP). We reported here this suggestive MPAL case of rare disease condition and effective treatment, in order to provide experience for the early diagnosis and treatment of similar patients.

Transformation of Chronic Myeloid Leukemia to Acute Biphenotypic Leukemia.

Chronic myeloid leukemia (CML) is a myeloproliferative disorder with clonal proliferation of all myeloid cell lines. The disease typically manifests in three phases: chronic course followed by an accelerated phase and finally a terminal blast crisis. A blast crisis is defined as the presence of > 20% blasts in the peripheral blood or bone marrow. The blasts could be characterized as either myeloid (60-80% of cases) resulting in acute myeloblastic leukemia or lymphoid (20-30% of cases) resulting in acute lymphoblastic leukemia. In rare instances, a blast crisis could present with biphenotypic expression for both myeloid and lymphoid blasts. In such cases, about 6-10% of the time, the course of the disease is more aggressive and renders a poorer prognosis especially if there is evidence of extramedullary involvement. We present a case of a 41-year-old woman with history of CML who presented with acute biphenotypic blast crisis with extramedullary involvement in the context of aggressive chemotherapy. Literature review reveals < 10 reported cases of CML with biphasic transformation and only three cases of CML with acute leukemia on presentation. Most cases described are in pediatric patients with varied presentations and none involving extramedullary sites. Mortality rates in such cases are near 100% despite aggressive chemotherapy.

Concomitant use of blinatumomab and donor lymphocyte infusion for mixed-phenotype acute leukemia: a case report with literature review.

Blinatumomab and donor lymphocyte infusion (DLI) combination is a promising cancer therapy, whereby blinatumomab might achieve an initial reduction in leukemic-cell burden using T cells, and after tumor clearance, DLI can potentially stimulate the donor immune system to achieve longer lasting remission. Here, we present a 51-year-old female with mixed phenotype acute leukemia who had a hematologic relapse 3 months after she received total body irradiation-based myeloablative allogeneic hematopoietic stem cell transplantation from an unrelated human leukocyte antigen matched (10/10) donor and achieved complete remission with minimal residual disease negativity by multi-parameter flow cytometry using the combination of blinatumomab and DLI. To the best of our knowledge, this is the first report to describe the use of blinatumomab and DLI combination therapy in the treatment of B/myeloid mixed phenotype acute leukemia.

Leucemia aguda de fenotipo mixto: presentación de un caso pediátrico de Perú / Acute leukemia of mixed phenotype: presentation of a pediatric case from Peru

Introducción: Las leucemias agudas de linaje ambiguo representan un grupo heterogéneo de leucemias sin una clara diferenciación del linaje celular. Constituyen alrededor de 2 a 5 por ciento del total de leucemias agudas. Objetivo: Describir un caso de leucemia aguda de fenotipo mixto (LAFM) en un paciente pediátrico de 4 años de Lambayeque, Perú. Presentación del caso: Se evaluó una muestra de sangre periférica de un niño de 4 años de edad, cuyo inmunofenotipo por citometría de flujo evidenció una población, correspondiente al 94 por ciento de la celularidad total, de linajes mieloide compatible con diferenciación a linaje neutrófilo y en menor medida a monocítica/célula dendrítica (CD123 intenso), con expresión de mieloperoxidasa (MPO) y CD33 intensos; CD13, CD64 y CD66c parcial; y expresión de marcadores de linaje linfoide B (CD19 y CD22 intensos). Este fenotipo obliga a descartar la t(8;21), y anomalías del gen MLL. Por los mencionados hallazgos, la presente leucemia fue clasificada como leucemia aguda de fenotipo mixto, B/Mieloide. Conclusiones: Se concluyó como una leucemia aguda de fenotipo mixto B/Mieloide, con la peculiar inclinación del linaje mieloide hacia neutrófilos y en menor medida hacia monocítica/célula dendrítica(AU)

Introduction: Acute leukemias of ambiguous lineage represent a heterogeneous group of leukemias without a clear differentiation of the cell lineage. They constitute about 2 to 5 percent of all acute leukemias. Objective: To describe a case of acute leukemia of mixed phenotype (LAFM) in a 4-year-old pediatric patient from Lambayeque, Peru. Case presentation: A peripheral blood sample from a 4-year-old boy was evaluated, whose immunophenotype by flow cytometry showed a population, corresponding to 94 percent of total cellularity, of myeloid lineages compatible with differentiation to neutrophil lineage and in less to monocytic/dendritic cell (CD123 high), with expression of myeloperoxidase (MPO) and CD33 high; CD13, CD64 and CD66c partial; and expression of B lymphoid lineage markers (CD19 and CD22 high). This phenotype requires ruling out the t (8; 21), and abnormalities of the MLL gene. Due to the aforementioned findings, the present leukemia was classified as acute leukemia of mixed phenotype, B/Myeloid. Conclusions: It was concluded as an acute leukemia of mixed phenotype B/Myeloid, with the peculiar inclination of the myeloid lineage towards neutrophils and to a lesser extent towards monocytic/dendritic cell(AU)

Mixed Phenotype Acute Leukemia with Low Hypodiploidy in a Pediatric Patient.

We describe the case of a 16 year-old female with mixed phenotype acute leukemia B/myeloid, NOS (formerly biphenotypic leukemia) with masked hypodiploidy and somatic TP53 and CDKN2A/B deletions. She achieved morphologic remission with lymphoid-directed multi-agent chemotherapy, but experienced an early medullary relapse 11 months from initial diagnosis. Her case details the unusual finding of hypodiploidy in a patient with ambiguous lineage leukemia and highlights the complexity of therapy selection for these high-risk patients.

Survival of patients with mixed phenotype acute leukemias: A large population-based study.

Little is known about the incidence and treatment outcome of patients with acute biphenotypic leukemias. The World Health Organization (WHO) established the term of acute leukemia of ambiguous phenotype in 2001 (revised in 2008) introducing the term of mixed phenotype acute leukemias. Using the database of the Surveillance, Epidemiology, and End Results registry (SEER), we identified 313 patients with mixed phenotype acute leukemias and compared them with 14,739 patients with acute lymphoblastic leukemia and 34,326 patients with acute myelogenous leukemias diagnosed between 2001 and 2011. As a further control group, 1777 patients were included who were not classified as myeloid, lymphoid or biphenotypic (other acute leukemias). The incidence of mixed phenotype acute leukemias is 0.35 cases/1,000,000 person-years. In a multivariate analysis, the prognosis depends strongly on age (as with other leukemias) and it has the worst outcome of all four types of leukemia. However, the prognosis has improved, comparing 2001-2005 with 2006-2011. We present the first comprehensive, population-based study of acute biphenotypic or mixed phenotype acute leukemias according to the WHO classification. Especially in older patients, the prognosis is unfavorable and new treatments should be investigated.

Frequency of p190 and p210 BCR-ABL rearrangements and survival in Brazilian adult patients with acute lymphoblastic leukemia.

OBJECTIVE: This study investigated the occurrence of the p190 and p210 breakpoint cluster region-Abelson (BCR-ABL) rearrangements in adults with acute lymphoblastic leukemia and possible associations with clinical and laboratory characteristics and survival. METHODS: Forty-one over 18-year-old patients with acute lymphoblastic leukemia of both genders followed-up between January 2008 and May 2012 were included in this study. Clinical and laboratory data were obtained from the medical charts of the patients. Reverse transcription polymerase chain reaction (RT-PCR) using specific primers was employed to identify molecular rearrangements. RESULTS: At diagnosis, the median age was 33 years, and there was a predominance of males (61%). The most common immunophenotype was B lineage (76%). BCR-ABL rearrangements was detected in 14 (34%) patients with the following distribution: p190 (28%), p210 (50%) and double positive (22%). Overall survival of patients with a mean/median of 331/246 days of follow up was 39%, respectively, negative BCR-ABL (44%) and positive BCR-ABL (28%). CONCLUSION: These results confirm the high frequency of BCR-ABL rearrangements and the low survival rate of adult Brazilian patients with acute lymphoblastic leukemia.

Acute leukemia of ambiguous lineage with trisomy 4 as the sole cytogenetic abnormality: A case report and literature review.

We describe a patient with acute leukemia of ambiguous lineage who had trisomy 4 as the sole cytogenetic abnormality. Clinical, pathological, immunophenotypic and molecular features are presented and compared with the previous 4 published cases. Over expression of c-kit, which is localized to chromosome 4, was documented on the leukemic blasts. Prognosis seems to be poor. Treatment with acute lymphoblastic leukemia like regimens seems to be superior compared to acute myeloid leukemia like regimens and allogeneic stem cell transplant is recommended after achieving remission.

A special case of acute leukemia in childhood.

Hybrid leukemia is a clinical entity that includes: biphenotypic leukemia, characterized by the presence of markers of more than two lineages of a single tumor cell, bilineage leukemia, a combination of more than two lineage markers on two distinct blast cells, and biclonal leukemia, the concomitancy of more than two types of leukemic cells, derived from different clonal expansions. We present a case of a 7-year-old female diagnosed with bilineage leukemia. We propose a treatment for biphenotypic/bilineage leukemia in the cases with good prognostic factors. We suggest that hematopoietic stem cell transplantation is often not required for cure of these patients.

Frequency of p190 and p210 BCR-ABL rearrangements and survival in Brazilian adult patients with acute lymphoblastic leukemia

Objective: This study investigated the occurrence of the p190 and p210 break point clusterregion-Abelson (BCR-ABL) rearrangements in adults with acute lymphoblastic leukemia and possible associations with clinical and laboratory characteristics and survival. Methods: Forty-one over 18-year-old patients with acute lymphoblastic leukemia of both genders followed-up between January 2008 and May 2012 were included in this study. Clinical and laboratory data were obtained from the medical charts of the patients. Reverse transcription polymerase chain reaction (RT-PCR) using specific primers was employed to identify molecular rearrangements. Results: At diagnosis, the median age was 33 years, and there was a predominance of males (61%). The most common immunophenotype was B lineage (76%). BCR-ABL rearrangements was detected in 14 (34%) patients with the following distribution: p190 (28%), p210 (50%) and double positive (22%). Overall survival of patients with a mean/median of 331/246 days of follow up was 39%, respectively, negative BCR-ABL (44%) and positive BCR-ABL (28%). Conclusion: These results confirm the high frequency of BCR-ABL rearrangements and the low survival rate of adult Brazilian patients with acute lymphoblastic leukemia...