A t(1;9)(p10;q10) in addition to two extra der(1;9)(q10;p10) chromosomes was observed in two patients of essential thrombocythemia that transformed to acute myelogenous leukemia or to myelofibrosis.
We herein report the first case in the literature, to our knowledge, of a 44-year-old female with essential thrombocythemia and severe myelofibrosis who developed acute myeloid leukemia (AML-M4) with der(1;15)(q10;q10) after 13 years of treatment.
A rare karyotypic event, der(1;15)(q10;q10), which involves the whole long arms of chromosomes 1 and 15, has been reported in patients with various conditions, including acute myelogenous leukemia, myelodysplastic syndrome, polycythemia vera, and multiple myeloma.
In contrast with other -7/7q- cases, where the abnormality tends to be found in one or more partial karyotypes, der(1;7)(q10;p10) represents the abnormality common to all the abnormal clones and usually appears as a sole chromosomal abnormality during the entire clinical courses, or if not, is accompanied only by a limited number and variety of additional abnormalities, mostly trisomy 8 and/or loss of 20q. der(1;7)(q10;p10)-positive MDS cases showed lower blast counts (P<0.0001) and higher hemoglobin concentrations (P<0.0075) at diagnosis and slower progression to acute myeloid leukemia (P=0.0043) than other -7/7q- cases. der(1;7)(q10;p10) cases showed significantly better clinical outcome than other -7/7q cases (P<0.0001).
Additional cytogenetic changes and previous genotoxic exposure predict unfavorable prognosis in myelodysplastic syndromes and acute myeloid leukemia with der(1;7)(q10;p10).
Idiopathic myelofibrosis developing isolated granulocytic sarcoma with der (1;7)(q10; p10) after splenectomy and finally transforming to acute myelogenous leukemia.