Standardization of molecular monitoring of CML: results and recommendations from the European treatment and outcome study.

Standardized monitoring of BCR::ABL1 mRNA levels is essential for the management of chronic myeloid leukemia (CML) patients. From 2016 to 2021 the European Treatment and Outcome Study for CML (EUTOS) explored the use of secondary, lyophilized cell-based BCR::ABL1 reference panels traceable to the World Health Organization primary reference material to standardize and validate local laboratory tests. Panels were used to assign and validate conversion factors (CFs) to the International Scale and assess the ability of laboratories to assess deep molecular response (DMR). The study also explored aspects of internal quality control. The percentage of EUTOS reference laboratories (n = 50) with CFs validated as optimal or satisfactory increased from 67.5% to 97.6% and 36.4% to 91.7% for ABL1 and GUSB, respectively, during the study period and 98% of laboratories were able to detect MR4.5 in most samples. Laboratories with unvalidated CFs had a higher coefficient of variation for BCR::ABL1IS and some laboratories had a limit of blank greater than zero which could affect the accurate reporting of DMR. Our study indicates that secondary reference panels can be used effectively to obtain and validate CFs in a manner equivalent to sample exchange and can also be used to monitor additional aspects of quality assurance.

Results of the European survey on the assessment of deep molecular response in chronic phase CML patients during tyrosine kinase inhibitor therapy (EUREKA registry).

PURPOSE: The advent of tyrosine kinase inhibitor (TKI) therapies has revolutionized the treatment of chronic myeloid leukemia (CML). The European LeukemiaNet (ELN) recommends quantification of BCR-ABL1 transcripts by real-time quantitative PCR every 3 months during TKI treatment. Since a proportion of patients in deep molecular response (DMR: MR4, MR4.5, MR5) maintain remission after treatment stop, assessment of DMR is crucial. However, systematically collected molecular data, monitored with sensitive standardized assays, are not available outside clinical trials. METHODS: Data were collected on the standardized assessment of molecular response in the context of real-life practice. BCR-ABL1 transcript levels after > 2 years of TKI therapy were evaluated for DMR by local laboratories as well as standardized EUTOS laboratories. Since standardized molecular monitoring is a prerequisite for treatment discontinuation, central surveillance of the performance of the participating laboratories was carried out. RESULTS: Between 2014 and 2017, 3377 peripheral blood samples from 1117 CML patients were shipped to 11 standardized reference laboratories in six European countries. BCR-ABL1 transcript types were b3a2 (41.63%), b2a2 (29.99%), b2a2/b3a2 (3.58%) and atypical (0.54%). For 23.72% of the patients, the initial transcript type had not been reported. Response levels (EUTOS laboratory) were: no MMR, n = 197 (6.51%); MMR, n = 496 (16.40%); MR4, n = 685 (22.64%); MR4.5, n = 937 (30.98%); MR5, n = 710 (23.47%). With a Cohen's kappa coefficient of 0.708, a substantial agreement between EUTOS-certified and local laboratories was shown. CONCLUSIONS: Multicenter DMR assessment is feasible in the context of real-life clinical practice in Europe. Information on the BCR-ABL1 transcript type at diagnosis is crucial to accurately monitor patients' molecular response during or after TKI therapy.

Prognostic Parameters of Acute Myeloid Leukaemia at Presentation.

INTRODUCTION: The treatment response and outcome in acute myeloid leukaemia (AML) is heterogeneous. AIM: To analyze the prognostic parameters of AML at presentation. METHODS: The total sample of 44 AML patients was analyzed on the basis of age <55 and ≥55 years, sex, WBC count <50x10/9/l and ≥50x10/9/l, the Hb concentration <100 g/l and ≥100 g/l, PLT count <100x10/9/l and ≥100x10/9/l, Karnofsky score <60% and >60%, cytogenetics, CD56 expression, morphological type and types of treatment (standard and reduced induction chemotherapy, high-dose chemotherapy/stem cell transplantation - autologous and HLA matched, related, allogeneic, together and separately). RESULTS: The age <55 years, Karnofsky score >60% and standard induction chemotherapy statistically correlated with the higher complete remission (CR) rates, longer relapse free survival (RFS), lower relapse rate (RR), and longer overall survival (OS) (p<0.01). The difference in terms of CR and RR between the sexes were not statistically significant (p<0.05), however women had statistically lower OS comparing to men (9.71±4.54 months vs. 38.03±9.17 months) (p<0.01). WBC count ≥ 50x10/9/l and the Hb concentration <100 g/l statistically correlated with shorter OS (p<0.05), while the WBC count ≥50x10/9/l statistically correlated with shorter RFS (p<0.05). The PLT count <100x10/9/l and ≥100x10/9/l was not found as prognostically significant for CR, RR, RFS, and OS (p<0.05). In comparison to the standard induction chemotherapy, both types of high dose chemotherapy/stem cell transplantation (HDT/SCT) (10/22), together and separately, resulted in longer RFS, lower RR, and longer OS (p<0.05). The frequency of cytogenetic risk was intermediate 81.6%, unfavorable 13.2%, and favorable 5.3%, respectively. CD56 + expression statistically correlated with the lower PLT count, higher RR, shorter RFS, and shorter OS (p<0.05). Statistical analysis of the cytogenetic risk and morphological types of AML were not possible due to the small number of patients in stratified groups. CONCLUSIONS: Female sex, the WBC count >50x10/9/l, the concentration of Hb <100 g/l, and CD56 + expression, at presentation of AML, should be considered as parameters of adverse risk, especially in latter decisions considering post-remission treatment with HDT/SCT.

Ten-year trends in prevalence of Down syndrome in a developing country: impact of the maternal age and prenatal screening.

OBJECTIVE: This study examines trends in total and live birth prevalence of trisomy 21 (T21) with regard to increasing maternal age and the introduction of prenatal diagnosis in Bosnia and Herzegovina. METHOD: The prenatal detection was introduced in January 2008 in 3 hospitals and assessed until December 31, 2015. In this study, 99 fetuses and 330 babies were diagnosed with T21 in the studied period. RESULTS: On average, each year 33 T21 individuals were born and 13 T21 fetuses were diagnosed prenatally. The calculated incidence for the live born T21 individuals in Bosnia is 1:999. The live-birth prevalence of T21 was 9.6 per 10,000 births and the total prevalence of T21 was 19.1. The total T21 prevalence increases exponentially with the advanced maternal age. Prenatal T21 prevalence is 1.29 per 10,000 births for mothers <35, but increases exponentially with increasing age (32 for >40 years). The most common indications for invasive prenatal testing were ultrasound screening combined with biochemical serum analysis followed by the advanced maternal age. CONCLUSION: The prevalence of liveborn Down syndrome children remained constant. Despite the fact that increasing maternal age in the last decade contributed to the rise in the total T21 prevalence, the effect of the introduction of prenatal diagnosis on the live-birth T21 prevalence of T21 was minimal, leading to the conclusion that the prenatal screening has to be improved in developing countries.