Chromosome 16 abnormalities associated with myeloid malignancies

Abstract

Twenty-six patients who had cytogenetic analyses performed for myeloid malignancies at St. Vincent's Hospital over a 6-year period were found to have an inversion abnormality of chromosome 16 (25 patients) or t(16;16) (1 patient). Only 16 patients had all the features of M4Eo, while the other 10 patients had diagnoses of M2, M4, M5, RAEB, and RAEB-T; six of these had abnormal eosinophils. Thus, abnormal eosinophils were present in 22 of 26 patients (85%). Thirteen patients had additional cytogenetic abnormalities at diagnosis, the commonest being +8 in 5, del(7q) in 4, and +21 in 3. Twenty-three patients received chemotherapy and 20 (87%) achieved complete remission. The median survival of the treated group was 188 weeks with a 61% 2-year and 45% 5-year survival. No significant difference in survival was observed between those patients with a diagnosis of M4Eo and those with other diagnoses suggesting that it is the abnormality of chromosome 16 which confers an improved prognosis. Additional cytogenetic abnormalities present at diagnosis did not affect prognosis. CNS relapse was observed in only two patients (8%), thus indicating no increased incidence of this complication. This study supports the premise that a chromosome abnormality involving 16p13 and 16q22 defines a good prognosis subset of myeloid leukemia despite morphological variations.

Real-time quantitation of minimal residual disease in inv(16)-positive acute myeloid leukemia may indicate risk for clinical relapse and may identify patients in a curable state

“…25 Comparisons of the CBF␤-MYH11/ABL ratios at diagnosis and relapse and during treatment and CR were performed by the Kruskal-Wallis test. 2 analysis was used for binary variables. All analyses were performed using the SPSS software package (SPSS, Chicago, IL).…”

“…Forty-eight of the samples positive at real-time RT-PCR had been negative at qualitative RT-PCR using the BIOMED-1 Concerted Action protocol. 2 analysis revealed that real-time RT-PCR was significantly more sensitive (P Ͻ .001).…”

“…[1][2][3][4] Inv(16) is associated with relatively good long-term, disease-free survival (DFS). 5,6 It generates a chimeric mRNA transcript, CBF␤-MYH11, by fusing the CBF␤ gene located on band q22 of chromosome 16 7,8 and the MYH11 gene, which encodes a heavy chain of the smooth-muscle myosin protein, located at the p13 breakpoint.…”

Molecular remission in PCR-positive acute myeloid leukemia patients with inv(16): role of bone marrow transplantation procedures

“…[2][3][4] The molecular marker is detectable by reverse transcription-polymerase chain reaction assay (RT-PCR) [5][6][7][8][9] on RNA at the time of diagnosis, and could be particularly useful for monitoring MRD in patients who achieve complete clinical remission (CCR) after induction therapy. [10][11][12][13] Marcucci et al 14 and several other authors [10][11][12][13] have reported favorable clinical outcomes despite persistence of CBF␤/MYH11 transcripts detected by RT-PCR; similar findings have been reported for another core-binding-factor altered in AML, 15,16 in which positive expression of AML1-ETO transcript can persist after induction and consolidation chemotherapy without evidence of hematological relapse.…”

“…However, the long-term survival is between 35 and 45%. 1,2 One of the possible explanations may be the infusion of tumor cells in the graft after high-dose chemotherapy. It has been shown that peripheral blood stem collections contain Hodgkin's cells.…”