Rearrangements of the chromosome 3 long arm, particularly in the q21/q26 band region, have been observed in acute nonlymphocytic leukemia (ANLL), chronic myelocytic leukemia(CML) and myelodysplastic syndromes. Thrombocytosis and abnormal megakaryocytopoiesis with the presence of micromegakaryocytes and hypolobulated nuclei are most often observed.
-5 or del(5)(q12q33)
The loss of chromosome 5, or the deletion of the chromosome 5 long arm (5q-) is most exclusively observed in acute nonlymphocytic leukemia (ANLL), preleukemia, myeloproliferative and myelodysplastic disease. The 5Q- has been reported to be associated with hematopoietic disease secondary to mutagenic exposure. The 5q- is often associated with an aggressive disease state and with a poor patient prognosis.
-7 or del(7)(q22)
The loss of chromosome 7 or the chromosome 7 long arm (7q-) is usually observed in acute nonlymphocytic leukemia (ANLL), myeloproliferative and myelodysplastic disorders and occasionally in acute lymphocytic leukemia (ALL). Monosomy 7 and del(7) have been reported to be associated with an aggressive disease state and with a poor patient prognosis.
Trisomy of chromosome 8 is almost exclusively observed in acute nonlymphocytic leukemia (ANLL:FAB-M2, M4 and M5), as a secondary chromosome change in chronic myelocytic leukemia (CML), and in myeloproliferative and myelodysplastic disease. Trisomy 8 is only rarely observed in lymphoid disease. As a secondary chromosome change in CML, trisomy 8 is often associated with cells in a blastic phase and associated with a relatively poor patient prognosis.
Trisomy or chromosome 9 has been most frequently observed in a wide variety of myeloid hematopoietic disease including acute nonlymphocytic leukemia (ANLL) and myelodysplastic syndromes, specifically myelofibrosis and polycythemia vera. Trisomy 9 is usually associated with other chromosome changes.
Del(11)(q23) or t(11;-)(q23;-)
Deletions of the 11q23 band region and rearrangements of this region with other chromosomes, specifically the t(9;11) rearrangement, are most frequently observed in acute nonlymphocytic leukemia (ANLL). These changes are almost exclusively associated with acute monocytic leukemia (AMoL:FAB-M5a). Exceptions include the t(4;11)(q21;q23) and t(11;14)(q23;q32) which are observed in acute lymphocytic leukemia. More specifically, the t(4;11) is frequently observed in biphenotypic ALL with monocytoid involvement. The myeloid 11q23 rearrangements are found most frequently in infants and young patients.
Del(13)(q12 or q14)
Deletions of the chromosome 13 long arm, particularly involving band 13q14 have been observed in a variety of neoplastic and pre-neoplastic disease. This deletion is most frequently observed in retinoblastoma, myeloproliferative and myelodysplastic disease as well as myelofibrosis.