AML with Additional Cytogenetic Abnormalities to t(8: 21) has Poorer Survival than that with Isolated t(8;21): A Retrospective Multicenter Cohort Study

Aim of the Study: To investigate the poor prognostic factors incriminated in AML with t (8; 21), particularly additional cytogenetic findings, clinicopathological presentation and their impact on survival rate in Egyptian and Saudi patients.

Study Design: Patients were collected from three centers: 9 cases from King Abdullah Medical City in Makah, between 2010 and 2013, 16 from King Fahad Medical City in Riyadh, Saudi Arabia between 2007 and 2013 and 16 patients from National Cancer Institute, Cairo University, Egypt 2010 and 2013.

Methodology: We studied 41 cases with t (8; 21). Immunophenotyping was performed using BD- FACS System. Conventional karyotypic analysis was done using standard culturing and banding techniques. Clinicopathological and cytogenetic data were correlated with disease outcome.

Results: There was no statistically significant difference between Egyptian and Saudi patients concerning the hematological parameters or immunophenotype markers expression, Thirty four (82.9%) out of 41 patients achieved complete remission. The follow up period for the whole group ranged from 2.1 to 170.3 weeks. The median survival was 146 weeks. The overall survival rate was 80% at one year and 70% at two years. Regarding the cytogenetic profile 33/41(80.5%) had isolated t(8;21) and 8 patients (19.5%) had a chromosomal aberration in addition to t(8;21); the commonest of which was + 8 that was found in 5 patients. The median overall survival of those 8 patients was 28.4 compared to 146.7 weeks in cases with isolated t (8; 21) p=0.002. Also, they had a lower one year overall survival rate (44%) than those with isolated t (8; 21) (86%) and their two years overall survival was zero.

Conclusion: AML associated with additional cytogenetic abnormalities to t (8;21) has poorer survival than that with isolated t(8;21). Trisomy 8 is mostly incriminated for this being the most commonly encountered in this study.