Inversions of chromosome 16 and rearrangements involving band 16q22 are almost exclusively observed in acute nonlymphocytic leukemia, specifically acute myelomonocytic leukemia (AMMoL:FAB-M4eo). This chromosome abnormality is associated with increased numbers of immature eosinophils in the bone marrow and peripheral blood. Eosinophils may show some nuclear hypo-segmentation and positive PAS/PE staining. These patients have been reported to frequently develop CNS leukemia. The inversion of chromosome 16 or a band 16q22 abnormality is reported to be suggestive of a relatively good patient prognosis.
This translocation is a remarkably specific marker for acute promyelocytic leukemia (ANLL-M3). This strong association is further exemplified by the fact that occasionally this translocation develops as a secondary aberration during CML blast transformation, with patients exhibiting disease characteristics indistinguishable from APL. Apart from these exceptional CML blast crisis patients, t(15;17) has not been detected in any malignancies other than ANLL-M3. t(15;17) APL patients usually exhibit disseminated intravascular coagulation (DIC) and hyper- or micro-granulated promyelocytes.
The t(11;22) is a relatively specific chromosome rearrangement found in over 80% of Ewings’ Sarcomas. This rearrangement has also been described in neurogenic tumors such as peripheral neuroepithelioma, Askins’ tumor, and esthesioneuroblastoma. Trisomy 8 is a common secondary chromosome change.
add(14)(q32) or 14q+
Additional chromosome material of unknown origin attached to band 14q32 has been observed in ALL and lymphoma. It is also a relatively frequent finding in B-cell CLL, prolymphocytic leukemia, hairy cell leukemia, Waldenstroms macroglobulinemia, multiple myeloma, plasma cell leukemia, ATL, mycosis fungoides and Sezary’s syndrome.
Deletions of the chromosome 20 long arm (20q) are most often observed in acute nonlymphocytic leukemia (ANLL), and myelodysplasic and myeloproliferative diseases, specifically polycythemia vera. Additional chromosome changes such as trisomy 8 and 9, rearrangements of the chromosome 1 long arm and deleted 13q are also observed and are associated with transformation to acute leukemia.