Outcome after allogeneic transplantation for adult acute myeloid leukemia patients exhibiting isolated or associated trisomy 8 chromosomal abnormality: a survey on behalf of the ALWP of the EBMT

Characteristics and outcome of patients with acute myeloid leukemia and trisomy 4

We retrospectively studied 125 patients with acute myeloid leukemia and trisomy 4 (median age at diagnosis, 58 years; range, 16-77 years) treated between 2000 and 2019 within a multicenter study. Trisomy 4 was the sole abnormality in 28 (22%) patients and additional abnormalities were present in 97 (78%) patients. Twenty-two (22%) and 15 (15%) of 101 tested patients harbored NPM1 and FLT3-ITD mutations. Two (3%) of 72 tested patients had double CEBPA mutations. Data on response to intensive anthracycline-based induction therapy were available for 119 patients. Complete remission was achieved in 67% (n=80) and the early death rate was 5% (n=6). Notably, patients with trisomy 4 as sole abnormality had a complete remission rate of 89%. Allogeneic hematopoietic cell transplantation was performed in 40 (34%) patients, of whom 19 were transplanted in first complete remission. The median follow-up of the intensively treated cohort was 5.76 years (95% confidence interval [95% CI]: 2.99-7.61 years). The 5-year overall survival and relapse-free survival rates were 30% (95% CI: 22-41%) and 27% (95% CI: 18-41%), respectively. An Andersen-Gill regression model on overall survival revealed that favorable-risk according to the European LeukemiaNet classification (hazard ratio [HR]=0.34; P=0.006) and trisomy 4 as sole abnormality (HR=0.41; P=0.01) were favorable factors, whereas age with a difference of 10 years (HR=1.15; P=0.11), female gender (HR=0.74; P=0.20) and allogeneic hematopoietic cell transplantation (HR=0.64; P=0.14) did not have an significant impact. In our cohort, patients with trisomy 4 as their sole abnormality had a high complete remission rate and favorable clinical outcome. Allogeneic hematopoietic cell transplantation did not seem to improve overall survival.

Risk Stratification, Measurable Residual Disease, and Outcomes of AML Patients with a Trisomy 8 Undergoing Allogeneic Hematopoietic Stem Cell Transplantation

BACKGROUND

For most patients with acute myeloid leukemia (AML) harboring a trisomy 8 an allogeneic hematopoietic stem cell transplantation (HSCT) is a suitable and recommended consolidation therapy. However, comparative outcome analyses between patients with and without trisomy 8 undergoing allogeneic HSCT have not been performed so far.

METHODS

We retrospectively analyzed clinical features, outcomes, and measurable residual disease (MRD) of 659 AML (12%, n = 81, with a trisomy 8) patients subjected to allogeneic HSCT as a consolidation therapy.

RESULTS

The presence of a trisomy 8 associated with a trend for higher age at diagnosis, AML of secondary origin, lower white blood cell counts at diagnosis, worse ELN2017 genetic risk, wild-type NPM1, and mutated IDH1/2 and JAK2. Outcomes after allogeneic HSCT in the entire cohort did not differ between patients with a sole trisomy 8, trisomy 8 with additional cytogenetic aberrations or without a trisomy 8. A trisomy 8 did not affect outcomes within the three ELN2017 risk groups. In accordance with findings in unselected patient cohorts, persistent MRD at allogeneic HSCT in patients with a trisomy 8 identified individuals with a higher risk of relapse following allogeneic HSCT.

CONCLUSIONS

Outcomes of trisomy 8 patients after allogeneic HSCT did not compare unfavorably to that of other AML patients following allogeneic HSCT. Rather than the presence or absence of a trisomy 8, additional genetic aberrations and MRD at HSCT define outcome differences and aid in informed treatment decisions.

Better leukemia-free survival with allogeneic than with autologous HCT in AML patients with isolated trisomy 8: a study from the ALWP of the EBMT

The indication for performing an allogeneic hematopoietic stem cell transplantation (allo-HCT) in patients with isolated trisomy 8 AML in first complete remission (CR) is still debated. Here, we compared outcomes of such patients given either allo-HCT or autologous (auto)-HCT. Inclusion criteria consisted of adult patients with de novo AML, isolated trisomy 8, first HCT between 2000 and 2018, CR1 at transplantation, and either auto-HCT or allo-HCT with a HLA-identical sibling donor (MSD) or a 10/10 HLA-matched unrelated donor (UD 10/10). A total of 401 patients met the inclusion criteria. They underwent an auto-HCT (n = 81), allo-HCT with a MSD (n = 186) or allo-HCT with a 10/10 UD (n = 134). At 3 years, relapse incidence, nonrelapse mortality and leukemia-free survival (LFS) were 59%, 5%, and 37%, respectively, in auto-HCT recipients; 31% (P < 0.001), 14% (P = 0.04), and 55% (P = 0.033), respectively, in MSD recipients and 29% (P < 0.001), 13% (P = 0.15), and 59% (P = 0.03), respectively, in UD 10/10 recipients. In multivariate analysis, in comparison to auto-HCT, MSD and UD 10/10 were associated with a lower risk of relapse (HR = 0.47, P < 0.001 and HR = 0.40, P < 0.001, respectively) translating to better LFS (HR = 0.69, P = 0.04 and HR = 0.60, P = 0.03, respectively). There was also a similar trend for overall survival (HR = 0.73, P = 0.12 and HR = 0.65, P = 0.08).

Trisomy 8 in acute myeloid leukemia

Introduction: Trisomy 8 is one of the most common cytogenetic alterations in acute myeloid leukemia (AML), with a frequency between 10% and 15%.Areas covered: The authors summarize the latest research regarding biological, translational and clinical aspects of trisomy 8 in AML.Expert opinion: Trisomy 8 can be found together with other karyotypes, although it also occurs as a sole aberration. The last decade's research has brought attention to molecular genetic alterations as strong contributors of leukemogenesis. AML with trisomy 8 seems to be associated with mutations in DNA methylation genes, spliceosome complex genes, and myeloid transcription factor genes, and these alterations probably have stronger implication for leukemic pathogenesis, treatment and hence prognosis, than the existence of trisomy 8 itself. Especially mutations in the RUNX1 and ASXL1 genes occur in high frequencies, and search for such mutations should be mandatory part of the diagnostic workup. AML with trisomy 8 is classified as intermediate-risk AML after recent European Leukemia Net (ELN) classification, and hence allogenic hematopoietic stem cell transplantation (Allo-HSCT) should be consider as consolidation therapy for this patient group.Trisomy 8 is frequently occurring in AML, although future molecular genetic workup should be performed, to optimize the diagnosis and treatment of these patients.

Clinical and molecular characterization of patients with acute myeloid leukemia and sole trisomies of chromosomes 4, 8, 11, 13 or 21

Sole trisomies of chromosomes 4, 8, 11, 13 and 21 account for 89-95% of all sole trisomies in adult AML patients. We analyzed clinical and molecular characteristics of 138 de novo AML patients with sole +4, +8, +11, +13 or +21, and compared them with AML patients with those trisomies occurring in addition to other chromosome abnormalities (non-sole trisomy) and with cytogenetically normal AML (CN-AML) patients. Mutations in methylation-related genes were most commonly observed within each sole trisomy group (+4, 55%; +8, 58%; +11, 71%; +13, 71%; +21, 75% of patients). Patients with sole trisomies, excluding +4, also had frequent mutations in spliceosome genes (+8, 43%; +11, 65%; +13, 65%; +21, 45% of patients). In contrast, +4 patients frequently had mutations in transcription factor genes (44%) and NPM1 (36%). While 48% of patients with sole trisomies harbored mutations in a spliceosome gene, spliceosome mutations were observed in only 24% of non-sole trisomy (n = 131, P < 0.001) and 19% of CN-AML patients (n = 716, P < 0.001). Our data suggest that mutations affecting methylation-related genes are a molecular hallmark of sole trisomies. Mutations in spliceosome genes were also commonly observed in many sole trisomy patients and represent a novel finding in this cytogenetic subgroup.

Incidence and prognostic significance of isolated trisomies in adult acute myeloid leukemia: A population-based study from the Swedish AML registry

OBJECTIVES AND METHODS

To ascertain the incidence/clinical implications of isolated autosomal trisomies in adult acute myeloid leukemia (AML), all such cases were retrieved from the Swedish AML Registry.

RESULTS

Of the 3179 cytogenetically informative AMLs diagnosed January 1997-May 2015, 246 (7.7%) had isolated trisomies. The frequency increased by age (2.4% at age 18-60 years vs. 23% at >60 years; P<.0001); the median age was 69 years. The five most common were +8 (4.0%), +13 (0.9%), +11 (0.8%), +21 (0.7%), and +4 (0.5%). Age and gender, types of AML and treatment, and complete remission and early death rates did not differ between the single trisomy and the intermediate risk (IR) groups or among cases with isolated gains of chromosomes 4, 8, 11, 13, or 21. The overall survival (OS) was similar in the single trisomy (median 1.6 years) and IR groups (1.7 years; P=.251). The OS differed among the most frequent isolated trisomies; the median OS was 2.5 years for +4, 1.9 years for +21, 1.5 years for +8, 1.1 years for +11, and 0.8 years for +13 (P=.013).

CONCLUSION

AML with single trisomies, with the exception of +13, should be grouped as IR.

Outcome of allogeneic hematopoietic stem cell transplantation in adult patients with acute myeloid leukemia harboring trisomy 8

Trisomy 8 (+8) is one of the most common cytogenetic abnormalities in adult patients with acute myeloid leukemia (AML). However, the outcome of allogeneic hematopoietic stem cell transplantation (HSCT) in adult patients with AML harboring +8 remains unclear. To evaluate, the outcome and prognostic factors in patients with AML harboring +8 as the only chromosomal abnormality or in association with other abnormalities, we retrospectively analyzed the Japanese registration data of 631 adult patients with AML harboring +8 treated with allogeneic HSCT between 1990 and 2013. In total, 388 (61%) patients were not in remission at the time of HSCT. With a median follow-up of 38.5 months, the probability of overall survival and the cumulative incidence of relapse at 3 years were 40 and 34%, respectively. In the multivariate analysis, two or more additional cytogenetic abnormalities and not being in remission at the time of HSCT were significantly associated with a higher overall mortality and relapse. Nevertheless, no significant impact on the outcome was observed in cases with one cytogenetic abnormality in addition to +8. Although more than 60% of the patients received HSCT when not in remission, allogeneic HSCT offered a curative option for adult patients with AML harboring +8.

A novel karyotype in acute myeloid leukemia with basophilia

Acute basophilic leukemia is a distinct entity of Acute Myeloid Leukemia (AML) with primary differentiation to basophils. Increased basophil count has been described in AML cases with translocation t(6;9)(p23;q34) or other chromosomal abnormalities. We describe a 15-year old female teenager with AML and excess peripheral blood and bone marrow basophils. Her white blood cell count at diagnosis was 15.4 G/L with 53% basophils and 17% blasts. The bone marrow cytogenetics analysis did not reveal any of the usual abnormalities. The karyotype showed two closely related leukemic clones: the first (16 metaphases), with a total of 48 chromosomes, had an extra chromosome 8 with deletion of the long arm and an additional 21 (48,XX, +del(8)(q24.2q24.3), t21[16]), while the second clone (2 metaphases), with a total of 47 chromosomes, did not contain the extra 21 chromosome (47, sl, -21[2]). In summary, in this case of AML-M2 with excess basophils, there is a novel chromosomal abnormality, not previously reported in this entity.