| Clinics and Pathology |
| Disease | Trisomy 19 (+19) as a sole karyotypic aberration is strongly associated with myeloid disorder. In a previously published literature review, among 31 patients with isolated +19, 25 were diagnosed with myeloid malignancy, including acute myeloid leukaemia (AML) in 14 cases and myelodysplastic syndrome (MDS) in 11 cases. Four out of the 14 AML patients had a preceding MDS phase, with +19 appearing at the time of leukaemic transformation. None of the MDS or AML cases, however, had a history of exposure to radiotherapy and chemotherapy. Hence isolated +19 is associated with a subgroup of de novo myeloid disorder, in which the clinical characteristics and prognostic impact require further delineation. As a secondary or additional abnormality, +19 is frequently encountered in chronic myeloid leukaemia (CML). Though not as common as trisomy 8, i(17q) and extra Ph chromosome, +19 is nevertheless seen in up to 15% of CML patients with additional abnormalities. Frequent gain of chromosome 19 or 19q was recently detected by comparative genomic hybridization in 4 out of 12 (33.3%) patients samples of acute megakaryoblastic leukaemia (AML-M7) and 9 out of 11 (81.8%) megakaryoblastic cell lines. In none of the primary patient samples was the abnormality detected by G-banding analysis. In another study on childhood and adult AML-M7, +19 was detected in 7 out of 53 patients, although as an additional abnormality in all cases. It appears +19 may play a role in the pathogenesis of megakaryoblastic leukaemia. |
| Etiology | Isolated +19 is probably associated with de novo myeloid disorders, as none of the AML and MDS cases with this abnormality reported had a history of prior radiotherapy or chemotherapy exposure. |
| Prognosis | Although isolated +19 is strongly associated with myeloid disorders, most probably de novo disease, its prognostic significance requires further elucidation. |
| Bibliography |
| Trisomy 19 in a patient with myelodysplastic syndrome and thrombocytosis. |
| Humphries JE, Wheby MS |
| Cancer genetics and cytogenetics. 1990 ; 44 (2) : 187-191. |
| PMID 2297677 |
| Trisomy 19 as the sole chromosomal anomaly in hematologic neoplasms. |
| Johansson B, Billstrm R, Mauritzson N, Mitelman F |
| Cancer genetics and cytogenetics. 1994 ; 74 (1) : 62-65. |
| PMID 8194050 |
| Frequent gain of chromosome 19 in megakaryoblastic leukemias detected by comparative genomic hybridization. |
| Alvarez S, MacGrogan D, Calasanz MJ, Nimer SD, Jhanwar SC |
| Genes, chromosomes & cancer. 2001 ; 32 (3) : 285-293. |
| PMID 11579469 |
| Chromosome 19 abnormalities are commonly seen in AML, M7. |
| Nimer SD, MacGrogan D, Jhanwar S, Alvarez S |
| Blood. 2002 ; 100 (10) : 3838-3839. |
| PMID 12411327 |
| Contributor(s) |
| Written | 06-2003 | Edmond S.K. Ma, Thomas S.K. Wan |
| Citation |
| This paper should be referenced as such : |
| Ma ESK, Wan TSK . Trisomy 19. Atlas Genet Cytogenet Oncol Haematol. June 2003 . URL : http://AtlasGeneticsOncology.org/Genes/tri19ID1039.html |
| © Atlas of Genetics and Cytogenetics in Oncology and Haematology | indexed on : Mon Jul 14 16:34:01 2008 |
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