Philadelphia chromosome-positive myelodysplastic syndrome: is it a distinct entity?

Aleukemic Chronic Myeloid Leukemia Without Neutrophilia and Thrombocytosis: A Report From the BCR::ABL1 Pathology Group

Chronic myeloid leukemia (CML) is characterized by leukocytosis with left-shifted neutrophilia, basophilia, eosinophilia, and variable thrombocytosis. However, extremely rare cases of patients with CML without significant leukocytosis and thrombocytosis (aleukemic phase [ALP] CML, or CML-ALP) have been reported. Due to its rarity and limited awareness, there remains a significant knowledge gap concerning the pathologic diagnosis, disease progression, and optimal patient management and outcomes. In this multi-institutional study, we investigated 31 patients with CML-ALP. Over half (54.8%) of patients had a history of or concurrent hematopoietic or nonhematopoietic malignancies. At time of diagnosis of CML-ALP, approximately 26.7% of patients exhibited neutrophilia, 56.7% had basophilia, and 13.3% showed eosinophilia. The median number of metaphases positive for t(9;22)(q34;q11.2) was 15, with a median of 38.5% of interphase nuclei positive for BCR::ABL1 by fluorescence in situ hybridization. The median BCR::ABL1 level was 26.14%. Remarkably, 14 (45.2%) patients were initially misdiagnosed or not diagnosed before karyotype or fluorescence in situ hybridization information for BCR::ABL1 became available. Twenty-five patients received tyrosine kinase inhibitors (TKIs). One patient developed blast crisis while on TKI treatment 8 months after initial diagnosis. With a median follow-up time of 46.1 months, 20 of 22 patients who received TKI therapy and had detailed follow-up information achieved complete cytogenetic remission or deeper, 15 achieved major molecular remission or deeper, and 10 achieved molecularly undetectable leukemia. In conclusion, given the frequent occurrence of prior or concurrent malignancies, aleukemic presentation, and low level of t(9;22)(q34;q11.2)/BCR::ABL1, misdiagnosis or delayed diagnosis is common among these patients. While these patients generally respond well to TKIs, rare patients may develop blastic transformation. It is therefore important for pathologists and hematologists to be aware of this highly unusual presentation of CML to ensure timely diagnosis and appropriate management.

Philadelphia chromosome- positive myelodysplastic syndrome with single lineage dysplasia

Myelodysplastic syndrome (MDS) is a group of acquired clonal disorders characterized by dysplastic and ineffective hematopoiesis in the bone marrow. Various specific karyotypic and molecular abnormalities associated with MDS further guide the prognosis. Although translocation t(9;22)(q34;q11) (Philadelphia positive [Ph+]) and corresponding BCR-ABL fusion transcript are classically defined to differentiate CML from non-CML myeloproliferative disorders, it is also associated with adult acute lymphoblastic leukemia (Ph+ ALL), acute myeloid Leukemia (Ph+ AML), myelodysplastic syndrome (Ph+ MDS). The occurrence of Ph+ MDS is very uncommon, and a review of literature has shown by far 40 cases so far in which the majority are seen on progression to Leukemia. Few had de novo presence of such chromosomal abnormality. Due to its rarity, this entity has not yet found its space in the current WHO classification. Also, the role of tyrosine kinase inhibitors in such a scenario is still debatable. We found two such cases of de novo Ph+ MDS diagnosed at institute of medical sciences, Banaras Hindu university and a brief literature review.

Philadelphia Translocation in MDS: A Case Report and a Brief Review of the Literature Looking at Its Prevalence, Disease Progression, and Treatment Options

Myelodysplastic syndrome (MDS) is a group of clonal disorders characterized by ineffective and dysplastic hematopoiesis in the bone marrow with variable risk of progression to leukemia. MDS is characterized by specific karyotypic and molecular abnormalities. The t(9 : 22) Philadelphia translocation is not a common abnormality found in MDS, and it is not included in the prognostic indices for germline mutations. There are no definitive treatment guidelines for these patients either. Here, we reviewed previously reported cases of MDS with the Philadelphia translocation with a goal to determine their prognosis and treatment options, specifically the tyrosine kinase inhibitors (TKIs).

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.

Uncovering Clinical Features of De Novo Philadelphia Positive Myelodysplasia

Myelodysplastic syndrome (MDS) is cytogenetically heterogeneous and retains variable risk for acute myeloid leukemia transformation. Though not yet fully understood, there is an association between genetic abnormalities and defects in gene expression. The functional role for infrequent cytogenetic alteration remains unclear. An uncommon chromosomic abnormality is the presence of the Philadelphia (Ph) chromosome. Here, we report a patient with Ph+ MDS treated with low dose Dasatinib who achieved hematologic response for 7 months. In addition, we also examined the English literature on all de novo Ph + MDS cases between 1996 and 2015 to gain insight into clinical features and outcome.