Differences between blastic chronic myeloid leukemia and Ph-positive acute leukemia

A Case Report of Chronic Myelogenous Leukemia Presenting as Blastic Crisis with a T-Cell Acute Lymphoblastic Leukemia Phenotype: Awareness of a Rare Entity

Chronic myelogenous leukemia at blast crisis with a T-cell phenotype (T-ALL CML-BC) at diagnosis, without any prior history of CML is extremely rare. After the introduction of tyrosine kinase inhibitors (TKIs), CML patients have a median survival comparable to general population and accelerated/blast crisis are rarely encountered. Most CML patients (80%) transform into acute myeloid leukemia and the rest into B-ALL. Anecdotal cases of Ph+ T-ALL, either de novo or in the context of CML-BC have been reported. Left shift in the blood, the presence of splenomegaly/extramedullary infiltration and the occurrence of BCR::ABL1 rearrangement in both the blastic population, as well as in the myeloid cell compartment are key points in differentiating de novo Ph+ T-ALL from T-ALL CML-BC. The latter is a rare entity, characterized by extramedullary disease, p210 transcript and clonal evolution. Lack of preceding CML does not rule out the diagnosis of T-ALL CML-BC. Prompt TKI treatment with ALL-directed therapy followed by allogeneic stem cell transplantation may offer long-term survival in this otherwise poor prognosis entity. In this paper, we describe a patient with T-ALL CML-BC at presentation, still alive 51 months after diagnosis and we offer a review of the literature on this rare subject. All clinical and laboratory features are provided in order to distinguish de novo Ph+ T-ALL from T-ALL CML-BC, underscoring the prognostic and therapeutic significance of such a differentiation.

Molecular Classification and Overcoming Therapy Resistance for Acute Myeloid Leukemia with Adverse Genetic Factors

The European LeukemiaNet (ELN) criteria define the adverse genetic factors of acute myeloid leukemia (AML). AML with adverse genetic factors uniformly shows resistance to standard chemotherapy and is associated with poor prognosis. Here, we focus on the biological background and real-world etiology of these adverse genetic factors and then describe a strategy to overcome the clinical disadvantages in terms of targeting pivotal molecular mechanisms. Different adverse genetic factors often rely on common pathways. KMT2A rearrangement, DEK-NUP214 fusion, and NPM1 mutation are associated with the upregulation of HOX genes. The dominant tyrosine kinase activity of the mutant FLT3 or BCR-ABL1 fusion proteins is transduced by the AKT-mTOR, MAPK-ERK, and STAT5 pathways. Concurrent mutations of ASXL1 and RUNX1 are associated with activated AKT. Both TP53 mutation and mis-expressed MECOM are related to impaired apoptosis. Clinical data suggest that adverse genetic factors can be found in at least one in eight AML patients and appear to accumulate in relapsed/refractory cases. TP53 mutation is associated with particularly poor prognosis. Molecular-targeted therapies focusing on specific genomic abnormalities, such as FLT3, KMT2A, and TP53, have been developed and have demonstrated promising results.

Primary Philadelphia chromosome positive acute myeloid leukemia: A case report

RATIONALE

Philadelphia chromosome positive acute myeloid leukemia (Ph+ AML) is a rare subtype of AML that is now included as a provisional entity in the 2016 revised WHO classification of myeloid malignancies. However, a clear distinction between de novo Ph+ AML and chronic myeloid leukemia blast crisis is challenging. It is still a matter of debate whether Ph+ AML patients should be treated with chemotherapy or tyrosine kinase inhibitors as first-line therapy.

PATIENT CONCERNS

We reported here a case of a 46-year-old man who was diagnosed as Ph+ AML. This diagnosis was confirmed by bone marrow pathology and karyotype analysis of 46, XY, t (9; 22). Further examination, molecular genetic analysis showed BCR/ABL1 (p190) without ABL1 kinase domain mutations, and direct evidence demonstrated in AML by flow cytometry.

DIAGNOSIS

The diagnosis of Ph+ AML was made on May 2016 according to morphology, immunology, cytogenetic, and molecular criteria, and multiple organ failure was also diagnosed.

INTERVENTIONS

The patient was treated with dasatinib as the only medication after experiencing multiple organ failure. Then, he received 2 cycles of chemotherapy with IA (idarubicin 8 mg/m, day 1-3; cytarabine 100 mg/m, day 1-7) in August, 2016.

OUTCOMES

The patient finally achieved a complete molecular remission.

LESSONS

This case study suggests that dasatinib can be a safe and effective treatment for Ph+ AML patients with poor physical condition.

Philadelphia chromosome-positive acute myeloid leukemia with masses and osteolytic lesions: finding of 18F-FDG PET/CT

Philadelphia chromosome-positive acute myeloid leukemia is controversial and difficult to distinguish from the blast phase of chronic myeloid leukemia. As a myeloid neoplasm, rare cases of this leukemia manifest multiple soft-tissue tumors or bone lytic lesions. In this paper, we describe a 49-year-old male patient who had an abrupt onset with sharp chest pain, fever, fatigue, emaciation, and splenomegaly. 18F-fluoro-deoxy-glucose positron emission tomography/computed tomography (18F-FDG PET/CT) result showed diffuse and uneven hypermetabolic lesions in the bone marrow with peripheral bone marrow expansion, multiple soft tissue neoplasms with high 18F-FDG uptake, and lytic bone lesions. Bone marrow smear and biopsy detected aberrant blast cells expressing myeloid rather than lymphoid immunophenotype marker. For the existence of Philadelphia chromosome and BCR-ABL1 fusion gene together with complex chromosome abnormalities, a diagnosis of Philadelphia-positive acute myeloid leukemia was made, although the type (de novo or blast crisis) remained unclear.

Philadelphia chromosome with acute myeloid leukemia and concurrent large B cell lymphoma of different origins: A case report

Philadelphia chromosome with de novo acute myeloid leukemia (Ph + AML) arising from t(9;22) is an uncommon occurrence. Ph + AML is known to respond poorly to conventional chemotherapy. To the best of our knowledge, simultaneous diagnosis of de novo Ph + AML and lymphoma in a single patient has not yet been reported. The present study reports the case of a 37-year-old female patient who presented with bone pain, fever and lymphadenopathy, and was diagnosed as Ph + AML with concurrent diffuse large B cell lymphoma. Combined chemotherapy regimen covering AML and lymphoma was administered, achieving short-term response. However, the therapy soon failed and the patient succumbed to the disease. The present study reports the first case of Ph + AML occurring concurrently with diffuse large B cell lymphoma, and discusses certain differences between Ph + AML and chronic myelogenous leukemia in the myeloid blast crisis phase, as well as the appropriate therapeutic modalities for Ph + AML. In addition, the potential association between Ph + AML and diffuse large B cell lymphoma in this patient was investigated.

Mixed phenotype acute leukemia with t(9;22): success with nonacute myeloid leukemia-type intensive induction therapy and stem cell transplantation

Mixed phenotype acute leukemia with t(9;22) is a rare disease with poor prognosis, and information on optimal treatment is limited. We describe a case where our patient experienced positive outcome after nonacute myeloid leukemia‐type intensive induction therapy followed by postremission therapy with stem cell transplant.

"Chronic myelogenous leukemia in primary blast crisis" rather than "de novo BCR-ABL1-positive acute myeloid leukemia"

Differentiating chronic myelogenous leukemia in primary blast crisis (CML‐BC) from de novo BCR‐ABL1‐positive acute myeloid leukemia (AML) is a diagnostic challenge with therapeutic consequences. In our case, a basophilia, the presence of the Philadelphia chromosome in all metaphases and the strict exclusion of molecular hallmarks of AML lead us to retain the diagnosis of CML‐BC rather than BCR‐ABL1+ AML.

BCR-ABL-positive acute myeloid leukemia: a new entity? Analysis of clinical and molecular features

BCR-ABL-positive acute myeloid leukemia (AML) is a rare subtype of AML that is now included as a provisional entity in the 2016 revised WHO classification of myeloid malignancies. Since a clear distinction between de novo BCR-ABL+ AML and chronic myeloid leukemia (CML) blast crisis is challenging in many cases, the existence of de novo BCR-ABL+ AML has been a matter of debate for a long time. However, there is increasing evidence suggesting that BCR-ABL+ AML is in fact a distinct subgroup of AML. In this study, we analyzed all published cases since 1975 as well as cases from our institution in order to present common clinical and molecular features of this rare disease. Our analysis shows that BCR-ABL predominantly occurs in AML-NOS, CBF leukemia, and AML with myelodysplasia-related changes. The most common BCR-ABL transcripts (p190 and p210) are nearly equally distributed. Based on the analysis of published data, we provide a clinical algorithm for the initial differential diagnosis of BCR-ABL+ AML. The prognosis of BCR-ABL+ AML seems to depend on the cytogenetic and/or molecular background rather than on BCR-ABL itself. A therapy with tyrosine kinase inhibitors (TKIs) such as imatinib, dasatinib, or nilotinib is reasonable, but-due to a lack of systematic clinical data-their use cannot be routinely recommended in first-line therapy. Beyond first-line treatment of AML, the use of TKI remains an individual decision, both in combination with intensive chemotherapy and/or as a bridge to allogeneic stem cell transplantation. In each single case, potential benefits have to be weighed against potential risks.

Erythroid blast crisis in chronic myelogenous leukemia: Case report and review of literature

Chronic myelogenous leukemia (CML) is a myeloproliferative disorder where over a period of time 15–20% of patients show blastic transformation with majority transforming into acute myeloid leukemia, most of which are of granulocytic lineage. Erythroid blast phase of CML is relatively rare with the incidence ranging from 0–10%. Further the incidence of acute erythroid leukemia by itself is fairly low amongst all acute leukemias. We report a case of 41-year-old patient with CML who failed to achieve cytogenetic remission, transformed to acute erythroid leukemia and eventually succumbed to the disease over a short period of time. Related literature is also reviewed

Isolated Ocular Manifestation of Relapsed Chronic Myelogenous Leukemia Presenting as Myeloid Blast Crisis in a Patient on Imatinib Therapy: A Case Report and Review of the Literature

Blast phase in chronic myelogenous leukemia (CML) has rarely been reported to involve extramedullary sites like skin, lymph nodes, and central nervous system. Clinical history, characteristic hematologic findings (elevated leukocyte counts, myelocytic predominance, and basophilia), and Philadelphia chromosome are of high diagnostic significance especially in isolated extramedullary presentations. We describe a unique case of CML relapse with blast phase involving the eye. A 66-year-old man with a known diagnosis of CML on imatinib and in molecular remission for 3 years presented with a painful blind eye. Histologic examination revealed diffuse involvement of choroid, iris, vitreous humor, and the optic nerve by blast cells. The blasts expressed CD34, aberrant TdT, and a myeloid phenotype (CD13, CD33, and CD117). Fluorescence in situ hybridization (FISH) of vitreous fluid detected BCR-ABL1 gene rearrangement. Additionally, trisomy 8 and gains of 9 and 22 were seen which were not present in the initial diagnostic marrow study 3 years ago. At relapse, the bone marrow, peripheral blood, and the cerebrospinal fluid were not involved by CML. Patient received induction chemotherapy and single dose prophylactic intrathecal methotrexate and was maintained on antityrosine kinase therapy and eventually underwent allogenic stem cell transplantation.

Chronic myelogenous leukemia presenting in blast phase with nodal, bilineal myeloid sarcoma and T-lymphoblastic lymphoma in a child

A 14-year-old boy presented with chronic myelogenous leukemia (CML) in blast phase with segregated extramedullary (nodal) myeloid sarcoma and T-lymphoblastic lymphoma. Immunohistochemical stains performed on the lymphadenectomy sample demonstrated T lymphoblasts in the lymph nodes and myeloblasts in the adjacent soft tissue. Fluorescence in situ hybridization performed on paraffin sections confirmed that both T-lymphoblast and myeloblast populations were positive for the t(9;22) BCR/ABL1 translocation. Subsequent flow cytometry analysis of the bone marrow showed expanded populations of abnormal myeloblasts and T lymphoblasts diagnostic of blast phase CML. To the best of our knowledge, bilineal blast phase of CML with segregated extramedullary T lymphoblasts and myeloblasts has not been reported.

Molecular characterization of de novo Philadelphia chromosome-positive acute myeloid leukemia

Philadelphia chromosome-positive (Ph+) acute myeloid leukemia (AML) is a controversial diagnosis, as others propose that it represents chronic myelogenous leukemia in blast phase (CML-BP). NPM1 mutations occur in 25-35% of patients with AML but are absent in patients with CML. Conversely, ABL1 mutations occur in 25% of imatinib-naive patients with CML-BP but are not described in patients with AML. We analyzed for NPM1 and ABL1 mutations in nine Ph+ patients with AML and five patients with CML-BP initially presenting in BP. In six cases of Ph+ AML, we screened for a panel of gene mutations using Sequenome(®)-based methods including AKT1, AKT2, AKT3, BRAF, EGFR, GNAQ, GNAS, IDH1, IDH2, KRAS, MET, NRAS, PIK3CA and RET. Two of nine (22%) patients with Ph+ AML had NPM1 mutations and were alive 36 and 71 months after diagnosis. All cases of Ph+ AML were negative for ABL1 and other gene mutations. One (20%) patient with CML-BP had ABL1 mutation; no patients had NPM1 mutations. These data suggest that Ph+ AML is distinct from CML-BP.

Philadelphia chromosome-positive acute myeloid leukemia: a rare aggressive leukemia with clinicopathologic features distinct from chronic myeloid leukemia in myeloid blast crisis

We performed a multi-institutional retrospective analysis of the morphologic features, immunophenotype, cytogenetics, and BCR-ABL transcript characterization of cases of Philadelphia chromosome-positive acute myeloid leukemia (Ph+ AML). We compared these cases with cases of documented chronic myelogenous leukemia in myeloid blast crisis (CML-MBC). Patients with Ph+ AML were less likely to have splenomegaly or peripheral basophilia and had lower bone marrow cellularity and myeloid/erythroid ratios than patients with CML-MBC. Additional specific cytogenetic abnormalities that typically occur in CML-MBC were less common in Ph+ AML. Of 7 patients with Ph+ AML treated with imatinib mesylate, 6 showed at least a partial hematologic response, but the responses were of a short duration (median, 2.5 months). The median survival of patients with Ph+ AML was 9 months, similar to that of patients with CML-MBC (7 months). Ph+ AML is a rare aggressive acute leukemia with some features distinct from CML-MBC.

Megakaryocytic blast crisis as first presentation of chronic myeloid leukemia

We describe an extremely rare case of megakaryocytic blast crisis as first presentation of chronic myeloid leukemia. The patient had a very high platelet count and developed an ischemic stroke with seizures. She was treated with hydroxyurea, platelet apheresis, ARA-C, and idarubicin in order to obtain a prompt reduction of thrombocytosis and then with imatinib 600 mg/die PO. The therapy induced a complete hematological remission with a resolution of neurological signs within 4 weeks.

Detection of BCR/ABL fusion product in normoblasts in a case of chronic myelogenous leukemia

Erythroblast phase of chronic myelogenous leukemia (CML) and Philadelphia chromosome-positive acute erythroid leukemia are rare events. The distinction between these two entities is poorly defined. The World Health Organization (WHO) classification requires the presence of more than 50% of erythroblasts in the bone marrow for the diagnosis of both the erythroid/myeloid or pure erythroid subtypes of acute erythroid leukemia. However, in previous studies of erythroblast crisis CML, the percentage of erythroid series in the bone marrow is seldom mentioned and the direct relationship of the erythroblasts and the Philadelphia chromosome has never been established. We report a well-documented case of acute erythroid leukemia transformed from CML. The studies in morphology, immunohistochemistry, and flow cytometry fulfill the WHO criteria for the diagnosis of acute erythroid leukemia, and yet the complex karyotype containing Philadelphia chromosome indicates genetic evolution. Finally, the direct demonstration of the BCR/ABL fusion product by fluorescence in situ hybridization in the erythroblasts provides concrete evidence that the erythroblasts are part of the leukemic process and not an innocent bystander.

Megakaryocytic blast crisis as a first presentation of chronic myeloid leukemia

Acute megakaryocytic leukemia (AmegL) corresponds to 5.0-10.0% of all acute myeloid leukemias (AML). Blast crisis as the first presentation of chronic myeloid leukemia (CML) accounts for 10.0% of all cases.

OBJECTIVE

We report a case of megakaryocytic blast crisis as the first presentation of CML.

CASE REPORT

A 25-yr-old-female with a 2-month history of dry cough and a large, non-tender splenomegaly was found to have a hemoglobin concentration of 10.5 g/dL, a hematocritof 33.0%, a white blood cell count (WBC) of 11.4 x 106 L with 38% small blasts, eosinophilia of 5%, basophilia of 8%, and a platelet count of 580 x 109 L. Bone marrow aspiration revealed 24% of blast cells with cytoplasmatic blebs and hyperplastic megakaryocytic lineage with dysplasia. Cytochemical stains were all negative, immunophenotyping studies showed CD41 and CD61 positivity in blast cells. Bone marrow biopsy showed grade II fibrosis. Karyotype revealed 46, XX, t(9,22) (q34.1;q11.2)[20] and the reverse-transcriptase-PCR (RT-PCR) gave rise a product with a size corresponding to the 210 kDa protein (p210). No matched donor was found. After induction therapy 5.9% of blast cells persisted. The patient received Imatinib Mesylate and is doing well after a 12-month follow-up.

DISCUSSION

AmegL as the first presentation of CML is a rare and often fatal event. Some characteristics point towards the diagnosis of a blast crisis instead of AmegL de novo with t(9,22).

Early events in leukemogenesis in P190Bcr-abl transgenic mice

The activated tyrosine kinase, Bcr-abl, is implicated in a number of hematopoietic malignancies. The exact biological mechanism by which the kinases transforms cells is still not well delineated. Previous data has suggested that the inhibition of apoptosis and the deregulation of cell cycle progression as the result of P210Bcr-abl expression might contribute to leukemogenesis. In vitro systems in which Bcr-Abl is over-expressed have concluded that similar growth regulatory pathways are affected as a result of the expression of both P210 and P190Bcr-abl. Here, we utilized an in vitro P190Bcr-abl leukemia mouse model to dissect the early events that contribute to transformation by this isoform of Bcr-Abl. In this mouse model P190Bcr-abl is expressed as a low but physiologically relevant level in that all mice develop pre-B leukemia lymphomas. We show that cell cycle and apoptotic responses to DNA damage are intact in bone marrow and spleen cells of such animals. We also demonstrate a normal induction of p21WAF-1/CIP1 in both hematopoietic and non-hematopoietic tissue as a result of genotoxic stress. We suggest that P190Bcr-abl induced transformation is different than that of P210Bcr-abl.

p190 BCR-ABL rearrangement in chronic myeloid leukemia and acute lymphoblastic leukemia

A minority of chronic myeloid leukemia (CML) cases have breakpoint in the minor cluster region (m-bcr) of the BCR-ABL fusion gene. We report a patient with Ph-positive acute lymphoblastic leukemia and m-bcr breakpoint at diagnosis. The patient was treated with chemotherapy followed by an autologous peripheral blood stem cell transplantation, achieving a clinical and hematological complete remission but with persistence of the Philadelphia chromosome. One year later, she developed leukocytosis with a blood picture consistent with CML. She was treated with hydroxyurea and interferon alpha with no response. This is the second case of m-bcr CML reported presenting with features of lymphoid blast crisis or acute lymphoblastic leukemia.

Chromosomal aberrations during progression of chronic myeloid leukemia identified by cytogenetic and molecular cytogenetic tools: implication of 1q12-21

To study the genomic abnormality underlying the acute transformation of chronic myeloid leukemia (CML), 15 CML patients in blast crisis (BC), 3 in accelerated phase (AP), and 20 in chronic phase (CP) were analyzed by conventional cytogenetics, comparative genomic hybridization (CGH), and dual-color chromosomal painting. Philadelphia (Ph) chromosome was identified in every case studied. Only 5 among 20 CP patients had additional abnormalities while 13 of 18 patients with disease progression (BC + AP) showed extra numerical and/or structural chromosomal aberrations. Cytogenetically, the most common chromosome gains during BC and AP were double or triple Ph chromosomes (5 of 14 cases) and trisomy 8 (5 of 14 cases). Trisomies 7 and 17 (1 of 14 cases each) were also observed. CGH analysis detected genetic imbalances in eight cases. Gains of chromosome 20 (3 cases) and 17q (2 cases) were observed, respectively. The recurrent chromosome loss was the deletion of the short arm of chromosome 17, seen in one case with i(17)(q10) and one case with an unbalanced translocation (1;17). In one case, a very complex chromosomal rearrangement, del(3),del(6),der(6)t(17;3;6),der(17)t(6;17), was seen. A novel finding of this work is the involvement of chromosome 1(q12-21qter) in CML disease progression. Overrepresentation of 1(q12-21qter) region was detected by CGH in one case which had a derivative chromosome 17. This abnormal chromosome was later confirmed by fluorescence in situ hybridization (FISH) painting to be a fusion between chromosome 1 and 17 to form the der(17)t(1;17) (q12-21;p11). Two other cases showed the same region being involved in translocations, t(1;10)(q12-21;q26) and t(1;11)(q12-21;p15). It is possible that one or more genes residing on chromosome 1q12-21 may be important in the acute transformation of CML. In conclusion, we find that the combined use of CGH, chromosome painting, and classic cytogenetic analysis allows a better evaluation of the genomic aberration involved in CML blastic transformation, and offers new directions for its further molecular investigations.

Minor breakpoint cluster region (m-BCR) positive chronic myeloid leukaemia with an acute lymphoblastic leukaemia onset: a case report

m-BCR chronic myeloid leukaemia (CML) is a rare entity. We report a patient presenting with Philadelphia (Ph)-positive, m-BCR-positive acute lymphoblastic leukaemia (ALL) who achieved complete remission after induction chemotherapy, but showed a majority of Ph-positive mitoses during this remission. A diagnosis of m-BCR CML was established and the patient was given interferon alpha therapy. This is the first m-BCR CML presenting as ab initio ALL. This report emphasizes the importance of karyotyping Ph-positive ALL during remission so as not to misdiagnose CML patients who can benefit from Interferon therapy.