Clinical diagnosis of adult patients with acute megakaryocytic leukemia

Abstract

Acute megakaryocytic leukemia (AMKL) is a rare subtype of acute myeloid leukemia (AML), which is challenging to diagnose due to frequent myelofibrosis (MF) and a low percentage of blast cells. In the present study, clinical characteristics and experimental observations in 9 adult patients diagnosed with AMKL, who were recruited by the Sino-U.S. Shanghai Leukemia Co-operative Group, were analyzed in order to summarize the diagnostic experience and provide recommendations on diagnosing AMKL. All the patients were diagnosed according to the 2008 World Health Organization diagnostic criteria. The mean age of the patients with AMKL was 59 years (range, 53–68 years). A total of 8 patients had different degrees of anemia, and 2 patients had <5% marrow blasts present in the bone marrow; however, the percentage of positive cells with cluster of differentiation (CD)41 and CD61 expression was >20%, as demonstrated by flow cytometry. A total of 6 patients were positive for platelet-specific antigens, as indicated by immunocytochemistry. Furthermore, 7 patients presented with moderate or marked MF, as demonstrated by a bone marrow biopsy. Karyotypic analysis indicated that 6 patients had abnormal karyotypes. Only 1 patient exhibited the Janus kinase 2V617F mutation. Treatment efficiency was notably poor, with a median survival time of 6.0 months (range, 1.1–24.0 months). In conclusion, the diagnosis of AMKL requires a combination of the results of bone marrow smears and bone marrow biopsy, immunophenotype or immunohistochemistry. We recommend that routine immunophenotypic analysis should include the CD41 and CD61 markers for diagnosing acute leukemia when bone marrow morphology does not indicate the diagnosis.

AML poor prognosis factor, TPD52, is associated with the maintenance of haematopoietic stem cells through regulation of cell proliferation

“…CD41 is used as a specific HSC marker during development in zebrafish embryos, and knockdown of tpd52 reduced the mRNA level of CD41 as well as the number of CD41 + cells in CHT (Figure 4C,D). CD41 is also known as a marker for myeloid‐biased haematopoietic stem cells, 28 and it is highlighted as a novel diagnostic molecule or therapeutic target in leukaemia 29 . Just as the expression of CD41 is decreased at tpd52‐MO‐injected embryos, similar pattern was observed in the human database.…”

Acute Coronary Syndrome in Acute Myeloid Leukemia with Maturation Accompanying Megakaryocytic Differentiation

“…AMKL belongs to acute myeloid leukemia, not otherwise specified, acute megakaryoblastic leukemia according to the World Health Organization classification 2017, or M7 according to the French-American-British (FAB) system. AMKL is defined as an AML with >20% blasts, of which >50% belong to the megakaryocyte lineage [ 7 – 10 ]. AMKL comprises 4–15% of AML in children [ 11 , 12 ], but in adults, AMKL occurs in <1% of AML patients [ 13 ].…”

“…Deficient expression of CD11a has been reported as another marker of AMKL [ 17 ]. Expression of the stem cell markers is inconsistent in AMKL [ 10 , 18 ]. Histopathologic features of MPO-negative AMKL reveal marked pleomorphism of neoplastic cells, ranging from myeloblast-like small round cells to large cells with an abundant cytoplasm, in the fibrotic bone marrow tissue [ 19 ].…”

A Case Report, An Adult with Acute Megakaryocytic Leukemia, Immunophenotyping Profile

“…In a previous report, there were 7 patients who had moderate and extensive myelofibrosis resulting in dry tap and inaccurate diagnosis of AML-M7 (9). Another study on AML-M7 also found that dry taps suggested a bone marrow biopsy to support the diagnosis (10).…”