BACKGROUND: Atypical chronic myeloid leukemia (aCML) is an infrequent chronic myeloproliferative disorder characterized by leukocytosis, absence of Philadelphia chromosome or BCR-ABL rearrangement, and marked myeloid dysplasia. Some cases have an absolute monocytosis but can be distinguished from chronic myelomonocytic leukemia (CMML) by the presence of a higher percentage (> 15%) of circulating immature granulocytes. PATIENTS AND METHODS: In a series of 11 patients with a diagnosis of aCML according to the FAB proposals we have analyzed the most relevant clinical, hematological and cytogenetic characteristics. RESULTS: The median age was 65 years (16-84). All but one case showed, at time of diagnosis, leukocytosis (median WBC was 36 x 10(9)/l), 55% had moderate anemia and 36% had thrombocytopenia. Most cases had marked dysplasia, particularly in the granulocytic lineage (82% of the cases), and all cases showed bone marrow red hypoplasia. Cytogenetic abnormalities were present in 9 out of the 11 patients. Trisomy 8 was observed in three cases and other clonal chromosomal abnormalities included deletions of 5q, 13q, 17p, 12q, and 11q as well as a t(6;8)(p23;q22) translocation. Fluorescence in situ hybridization (FISH) studies failed to demonstrate ETV-6 gene involvement. The median survival time from diagnosis was only 14 months (range 3-56 months). CONCLUSIONS: These data suggest that aCML is a rare disease which is characterized by leukocytosis, with dysgranulopoiesis, BM erythroid hypoplasia, chromosomal, though not recurrent, abnormalities and poor prognosis.
Clinical, hematological and cytogenetic characteristics of atypical chronic myeloid leukemia
CUNEO, Antonio;CASTOLDI, Gianluigi;
2000
Abstract
BACKGROUND: Atypical chronic myeloid leukemia (aCML) is an infrequent chronic myeloproliferative disorder characterized by leukocytosis, absence of Philadelphia chromosome or BCR-ABL rearrangement, and marked myeloid dysplasia. Some cases have an absolute monocytosis but can be distinguished from chronic myelomonocytic leukemia (CMML) by the presence of a higher percentage (> 15%) of circulating immature granulocytes. PATIENTS AND METHODS: In a series of 11 patients with a diagnosis of aCML according to the FAB proposals we have analyzed the most relevant clinical, hematological and cytogenetic characteristics. RESULTS: The median age was 65 years (16-84). All but one case showed, at time of diagnosis, leukocytosis (median WBC was 36 x 10(9)/l), 55% had moderate anemia and 36% had thrombocytopenia. Most cases had marked dysplasia, particularly in the granulocytic lineage (82% of the cases), and all cases showed bone marrow red hypoplasia. Cytogenetic abnormalities were present in 9 out of the 11 patients. Trisomy 8 was observed in three cases and other clonal chromosomal abnormalities included deletions of 5q, 13q, 17p, 12q, and 11q as well as a t(6;8)(p23;q22) translocation. Fluorescence in situ hybridization (FISH) studies failed to demonstrate ETV-6 gene involvement. The median survival time from diagnosis was only 14 months (range 3-56 months). CONCLUSIONS: These data suggest that aCML is a rare disease which is characterized by leukocytosis, with dysgranulopoiesis, BM erythroid hypoplasia, chromosomal, though not recurrent, abnormalities and poor prognosis.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
