Introduction: Acute myeloblastic leukemia (AML) is an umbrella term for a heterogeneous group of clonal neoplastic diseases of hematopoietic cells. Detecting residual leukemic cells (measurable residual disease - MRD) is the most important prognostic and predictive factor in AML. The aim: The study aims to analyze the effect of administered chemotherapy based on the results of MRD testing in patients with AML treated at the University Clinical Center of Serbia (UCCS) Clinic for Hematology. Materials and methods: Our study included the analysis of 111 AML patients, treated between January 2020 and January 2024. All diagnostic procedures performed were based on the most recent recommendations of European LeukemiaNet (ELN). Results: MRD+ patients who continued treatment with intensive chemotherapy (CHT), using full doses of 3+7 CHT as reinduction therapy, had a significantly longer remission (complete remission - CR) and a longer overall survival (OS). The duration of CR (p = 0.004) and OS (p = 0.019) were statistically significantly longer in patients who maintained a negative MRD status at the end of treatment. In transplanted patients, overall survival (OS; p = 0.006) and duration of remission (CR; p = 0.002) were significantly longer (median: OS 20 months; CR 21 months), as compared to the group of non-transplanted patients (median: OS 13 months; CR 8 months). Discussion: Measurable residual disease (MRD) can be both prognostic and predictive. However, the absolute measurable level of the disease is not the only determinant of the patient's outcome, since the biology of AML, as well as other clinical patient-related factors (age, comorbidities, various complications of applied chemotherapy, especially infections), modify the risk associated with MRD test results. Conclusion: The study has demonstrated the great importance of timely detection of MRD, as well as the appropriateness of applying more intensive CHT in MRD-positive patients, along with continued treatment with allogeneic hematopoietic stem cell transplantation.

Examination of central nervous system (CNS) involvement is not routine diagnostic practice in adult patients with acute myeloid leukemia (AML). Therefore, many asymptomatic patients with CNS involvement might go undetected. The effect of CNS involvement on the AML disease course is not well defined, with conflicting results regarding clinical outcome. This study aimed to determine the incidence of asymptomatic CNS involvement in AML estimated by multiparametric flow cytometry of cerebrospinal fluid (MFC-CSF) at diagnosis, the related potential risk factors, and prognosis. In total, 645 patients with de novo AML were screened; 183 (28.4%) of them fulfilled institutional practice for MFC-CSF analysis based on presence of CNS symptoms and/or clinical features. CNS symptoms and signs were observed in 8/183 (4.4%) patients, but most patients (175/183, 95.6%) were asymptomatic. In the asymptomatic group, 73/175 (41.7%) patients had positive or suspicious cerebrospinal fluid (CSF) findings categorized as CNS positive (CNSpos) and 102/175 (58.3%) had normal CNS findings categorized as CNS negative (CNSneg). The presence of leukemic blasts was confirmed in 81/183 (44.3%) patients; the total incidence of CNS involvement in the whole AML group was 12.6% (81/645). Compared with asymptomatic patients with CNSneg, those with CNSpos had a significantly higher frequency of lymphadenopathy, white blood cell count >= 30 x 109/L, presence of the monocytic phenotype, and a high percentage of bone marrow (BM) blasts. The multivariate logistic regression model identified monocytic phenotype (p = 0.047) and high percentage of BM blasts (p = 0.042) as predictors for CNSpos. CNSpos did not affect overall survival in patients with AML. There was a higher incidence of CNS involvement in asymptomatic adult patients with de novo AML, emphasizing possible undervalued rates of CNS disease at diagnosis. Prospective studies should determine whether diagnostic lumbar puncture for MFC-CSF analysis and CNS prophylaxis could contribute to better selection and prognosis in this patient population.

Introduction/Aim: Acute myeloid leukemia (AML) is a heterogeneous disease, in terms of its biological characteristics and response to therapy. Numerous prognostic factors at diagnosis related to the disease itself, the treatment, and the response to treatment influence the outcome of AML. Despite the high rate of complete remission, overall survival (OS) is still poor. This study aims to determine the clinical and biological profile of patients with AML and its prognostic impact on the OS rate and disease-free survival (DFS). Materials and methods: The retrospective analysis included 271 patients diagnosed with acute myeloid leukemia at the University Clinical Center of Serbia (UCCS) Hematology Clinic, between January 2018 and January 2023. Demographic parameters, the Eastern Cooperative Oncology Group performance status (ECOG PS), comorbidities, and the parameters of laboratory analysis and hematological diagnosis of AML were analyzed as potential risk factors for OS and DFS, using the univariate Cox regression model. Results: Out of a total of 271 patients, 206 (76%) were treated with intensive chemotherapy, of whom 108 were men and 98 were women. The average age of these respondents was 50.3 years. According to the European Leukemia Network (ELN) risk classification, the patients were mostly in the group with intermediate risk, i.e. 128 (62.1%) patients. The most common subtype of AML was AML NOS (AML not otherwise specified), present in 123 (59.7%) patients. Univariate analysis showed that age ≥ 60 years (p = 0.009) and WBC ≥ 30 x 109 /l (p = 0.031) were unfavorable prognostic parameters for OS. AML subtype, MRC (myelodysplasia-related changes) was the most significant risk factor for shorter disease-free survival (p = 0.027). Conclusion: In the analyzed group of AML patients treated with intensive therapy, we demonstrated a low OS rate and showed that age and the MRC subtype of AML represent unfavorable risk factors for shorter OS and DFS, respectively.

Background: Patients with hematological malignancies have an increased risk of arterial thrombotic events (ATEs) after diagnosis, compared to matched controls without cancer. However, data about incidence and risk factors for ATE development in patients with acute myeloid leukemia (AML) are missing. Aim: The objectives of this study were to determine the incidence of ATE in non-promyelocytic-AML patients and to define the potential risk factors for ATE development. Methods: We conducted a retrospective cohort study of adult patients with newly diagnosed AML. The primary outcome was the occurrence of confirmed ATE, defined as myocardial infarction, stroke or critical limb ischemia. Results: Out of 626 eligible AML patients, 18 (2.9%) patients developed ATE in the median time of 3 (range: 0.23-6) months. Half of these patients died due to ATE complications. Five parameters were predictors of ATE: BMI > 30 (p = 0.000, odds ratio [OR] 20.488, 95% CI: 6.581-63.780), prior history of TE (p = 0.041, OR 4.233, 95% CI: 1.329-13.486), presence of comorbidities (p = 0.027, OR 5.318, 95% CI: 1.212-23.342), presence of cardiovascular comorbidities (p < 0.0001, OR 8.0168, 95% CI: 2.948-21.800) and cytogenetic risk score (p = 0.002, OR 2.113, 95% CI: 1.092-5.007). Conclusions: Our study showed that patients with AML are at increased risk of ATE. The risk was increased in patients with cardiovascular comorbidities, previous thrombosis, adverse cytogenetic risk as well as BMI > 30.

Topic: 30. Infections in hematology (incl. supportive care/therapy) Background: Intensive chemotherapy/radiotherapy in patients with acute leukemias causes cellular injury and suppression of inflammatory responses, which increase the risk of neutropenia and febrile episodes. FN remains a common complication in chemotherapy causing serious clinical results, including death. Wide application of broad-spectrum antibiotics has effectively decreased the mortality of FN patients. Neutropenic patients who remain febrile despite 4-7 days of broad spectrum antibacterial therapy are at a high risk of invasive fungal infection. Empirical antifungal therapy with liposomal Amphotericin B or Caspofungin in high risk patients has shown to reduce the risk of invasive fungal infection by 50-80% and the risk of fungal infection related mortality by 23¬ 45%. Aims: The aim of study was to analyze frequency, causes, treatment and outcome of infectious complications in patients with acute leukemia. Methods: Sixty patients (pts) with acute leukemia treated between January 1, 2021 and March 2022 at the Clinic of Hematology, University Clinical Center of Serbia were examined. Median age was 60yrs (range 21-76yrs, F/M: 35/25pts). The diagnosis of acute leukemia was made based on WHO 2016 criteria and ELN 2022 recommendations. The principles of diagnosis and treatment of infectious complications according to ESMO 2016, NCCN 2019, ECIL-6, 2017 were applied. Patients are treated with the use of broad-spectrum antibiotics according to the de-escalation principle, and if a diagnosis of possible/probable IA is made, with the use of Voriconazole or the lipid formulation of Amphotericin. Statistical analysis was performed using the IBM SPSS 21 (Chicago, IL, USA, 2012) package. Results: AML was diagnosed in 48pts, APL in 4pts; ALL 6pts, MPAL 2 patients. 17/60 patients had a favorable cytogenetic/molecular form of the disease; 26/60pts intermediate and 17/60ptsadvers e risk group. In relation to the treatment phase: 33/60pts received induction therapy; 28/60pts consolidation; reinduction in 7/60pts; salvage protocol in 10/60pts, while 10/60pts were treated only with supportive therapy. Febrile neutropenia occurred in 50/60pts (83.3%); with a median duration of aplasia of 12 days (5-27). Blood cultures were positive in 19% of analyzed samples (183/963). The most common isolates were: Klebsiella 46.4%; E Coli 8.7%; Enterococcus 8.7%; Pseudomonads aeruginosa 9.8%; Coagulase-negative Staphylococcus 15.8%; Acinetobacet 0.5%; Staphylococcus aureus 0.5%, remaining 9.3%. In relation to the diagnosis of IA, non-culture techniques showed positive beta2 glucan in 13/60pts, and elevated values of antiAspergillus IgM and antiAspergillus IgG antibodies in 33/60pts. Chest HRCT showed the following results; normal findings in 35/60pts, GGO in 11/60pts; nodular changes in 11/60pts and consolidation in 3/60pts. 15/60pts had possible IA, and 10/6 - probable IA. Outcome: at the time of examination, 32/60pts were alive (53.3%). Median survival was 206 days (range 5-1801 days). Summary/Conclusion: Bearing in mind that serious infections in patients with hematological malignancies are the main cause of morbidity and mortality, it is necessary to further develop a strategy for the prevention and treatment of febrile neutropenia. Prompt application of empiric/preeptive antibiotic and antifungal therapy is crucial for the outcome of the treatment of these high-risk hematological patients. The teamwork of hematologists, microbiologists, infectious disease specialists, epidemiologists, and radiologists is extremely important. Keywords: Acute leukemia

Intensive chemotherapy/radiotherapy in cancer, especially with hematologic malignancies, causes cellular injury and suppression of inflammatory responses, which increase the risks of neutropenia and febrile episodes. Absolute neutrophil count < 1 ? 109/L is considered neutropenia, with absolute neutrophil count < 0.5 ? 109/L or < 1 ? 109/L that is expected to decrease to < 0.5 ? 109/L in the next 48 hours considered severe neutropenia, while absolute neutrophil count < 0.1 ? 109 is referred as profound neutropenia. Febrile episodes are usually defined as oral temperature > 38.3?C or two consecutive readings > 38.0?C lasting more than 1 hour. Although there is the possibility of non-infection-caused febrile neutropenia, most episodes are caused by infections. Febrile neutropenia is a clinical emergency that requires prompt management. Despite advances in therapy in recent years, febrile neutropenia remains a common complication in chemotherapy causing serious clinical results, including death. The administration of empirical antibacterial therapy has been successful in the management of febrile neutropenia since its launching 50 years ago. The wide application of broad-spectrum antibiotics has effectively decreased the mortality of febrile neutropenia patients. Neutropenic patients who remain febrile despite 4-7 days of broad-spectrum antibacterial therapy are at a high risk of invasive fungal infection. Empirical antifungal therapy with Amphotericin B or Caspofungin in persistently febrile neutropenic patients and other high-risk patients has shown to reduce the risk of invasive fungal infection by 50 - 80% and the risk of fungal infection-related mortality by 23- 45%. Lipid formulations which improve the therapeutic ratio of the traditional formulation are available

Patients with coronavirus disease 19 (COVID-19) have increased susceptibility to secondary respiratory infections including invasive pulmonary aspergillosis (IPA). COVID-19-associated pulmonary aspergillosis (CAPA) is difficult to diagnose and can be associated with increased mortality especially in severe immunodeficiency such as hematological malignancies. Our study evaluates IPA in COVID-19 patients defined as COVID-19-CAPA among patients with acute leukemia (AL). A retrospective single-center study analyzed 46 patients with COVID-19 infection and acute leukemia, admitted to the Clinic for Haematology, Clinical Center of Serbia, Belgrade between the 2 April 2020 and 15 May 2021. During hospitalization, all participants were diagnosed with probable IPA according to the previous consensus definitions. Positive serology and galactomannan (GM) detection values in bronchoalveolar lavage (BAL) and serum were used as microbiological criteria. COVID-19 associated probable IPA was found in 22% (9/41) tested patients, where serum GM and IgM anti-Aspergillus antibodies were positive in 12% (5/41) and 10% (4/41) had positive serology for aspergillosis. One patient died while eight recovered during follow-up. Our study showed that COVID-19 might be a risk factor for IPA development in patients with AL. Early diagnosis and prompt treatment are required as reported mortality rates are high.

PURPOSE:Imatinib mesylate transformed the treatment and paradigms of chronic myeloid leukemia. European LeukemiaNet (ELN) group has defined specific treatment milestones with an optimal outcome to be achieved in patients.METHODS:In a retrospective cohort study, we evaluated the impact of clinical and biological variables on achieving an optimal response at 6 and 12 months according to ELN recommendations. We included 106 patients with chronic phase chronic myeloid leukemia (CML) with appropriate bone marrow aspirate and biopsy for immunohistochemistry.RESULTS:The number of white blood cells (WBC), the percentage of peripheral blast, the values of Sokal and ELTS scores and the percentage of Ki-67+ cells in the bone marrow predicted a complete cytogenetic response (CCyR) at 6 months, but only WBC and EUTOS score predicts CCyR at 12 months. We found that Sokal score below 0.775 was very sensitive to achieve of CCyR at 6 months (m) and that all patients with a value <0.550 achieved CCyR-6m. Patients with a low percentage of blast in the peripheral blood (≤1.5%) or in the bone marrow (≤5%) together with lower WBC (≤100×109/L) were likely to have significantly higher CCyR rates at 6 and 12 months respectively. Also, patients with a higher number of Ki67+ cells in the leukemic areas of the bone marrow had a significantly better outcome. Unfortunately, our investigation did not reveal that bone marrow fibrosis (MF grade), microvascular density, percentage of CD34+, CD61+ or PTCH1+ cells could have any effect on achievement of CCyR at 6 or 12 months.CONCLUSION:Our investigation has shown that only a few biological characteristics in patients with CML can predict the optimal treatment outcome after imatinib.

PURPOSE:We compared the gene expression profile of peripheral blood CD34(+) cells and granulocytes in subjects with chronic myeloid leukemia (CML), with the accent on signaling pathways affected by BCR-ABL oncogene. METHODS:The microarray analyses have been performed in circulating CD34(+) cells and granulocytes from peripheral blood of 7 subjects with CML and 7 healthy donors. All studied BCR-ABL positive CML patients were in chronic phase, with a mean value of 2012±SD of CD34(+)cells/μl in peripheral blood. RESULTS:The gene expression profile was more prominent in CML CD34(+) cells (3553 genes) compared to granulocytes (2701 genes). The 41 and 39 genes were significantly upregulated in CML CD34(+) cells (HINT1, TXN, SERBP1) and granulocytes, respectively. BCR-ABL oncogene activated PI3K/AKT and MAPK signaling through significant upregulation of PTPN11, CDK4/6, and MYC and reduction of E2F1, KRAS, and NFKBIA gene expression in CD34(+) cells. Among genes linked to the inhibition of cellular proliferation by BCR-ABL inhibitor Imatinib, the FOS and STAT1 demonstrated significantly decreased expression in CML. CONCLUSION:The presence of BCR-ABL fusion gene doubled the expression quantity of genes involved in the regulation of cell cycle, proliferation and apoptosis of CD34(+) cells. These results determined the modified genes in PI3K/AKT and MAPK signaling of CML subjects.

BACKGROUND/AIM:Bronchus-associated lymphoid tissue (BALT) lymphoma is a rare subtype of low grade marginal zone B cell lymphoma representing 10% of all MALT lymphomas. The purpose of this study was to analyze the outcome of this group of patients comparing prognostic parameters and therapy modalities.METHODS:A total of eight patients with BALT lymphoma had diagnosed between January 1998-April 2008 at the Institute of Hematology, Clinical Center of Serbia, Belgrade, and they were included in this retrospective analysis.RESULTS:Male/female ratio was 2/6, the median age was 64 years (range 37-67 years). Six patients had nonspecific respiratory symptoms and all of them had B symptoms. The patients were seronegative for HIV, HCV and HBsAg. Three patients had Sjogren's syndrome, rheumatoid arthritis and pulmonary tuberculosis, respectively. Seven patients were diagnosed by transbronchial biopsy and an open lung biopsy was done in one patient. Patohistological findings revealed lymphoma of marginal zone B cell lymphoma: CD20+/CD10-/CD5-/CyclinD1/CD23-/IgM- with Ki-67+< 20% of all cells. According to the Ferraro staging system, five patients had localized disease (CS I-IIE) and three had stage IVE; bulky tumor mass had 3 patients. All patients had Eastern Cooperative Oncology Group (ECOG) performance status (PS) 0 or 1. Five patients received monochemotherapy with chlorambucil and 3 were treated with CHOP regimen (cyclophosphamide, doxorubicin, vincristine and prednisone). A complete response (CR) was achieved in 5 patients and a partial response (PR) in 3 of them, treated with chlorambucil monotherapy and CHOP regimen. All patients were alive during a median follow-up period of 49 months (range 6-110 months). Three patients relapsed after monochemotherapy into the other extranodal localization. They were treated with CHOP regimen and remained in stable PR. CONCLUSION. BALT lymphoma tends to be localised disease at the time of diagnosis, responds well to monochemotherapy with chlorambucil and has a favourable prognosis.

Nehockinski limfomi danas predstavljaju kamen temeljac savremenoj onkohematologiji, s obzirom na mogucnost visokog procenta njihovog izlecenja. Najcesca podgrupa limfoma su DBKL koji su kod oko 30% bolesnika izlecivi primenom konvencionalne terapije, dok su FL neizlecivi ukoliko se lece samo konvencionalnom terapijom. Istina je da se kod bolesnika sa FL terapijski odgovor postize brzo, ali recidivi se gotovo po pravilu desavaju i bolesnike je u svakom sledecem recidivu sve teze leciti. Sredinom devedestih godina napravljeno je prvo monoklonsko antitelo u lecenju malignih bolesti, i to najpre za recidive ili refraktarne FL. Ovo anti CD20 monoklonsko antitelo, rituksimab, predstavlja krucijalan napredak u lecenju limfoma, jer je primenom kombinoivane imunohemioterapije izlecenje DBKL poraslo na oko 60%, a poslednje studije ukazuju na mogucnost dugotrajnih remisija i PFS za FL, sto moze biti ekvivalent izlecenju i ove podgrupe limfoma. U toku su brojne studije kojima se vrse uporedne analize za primenu ritoksimaba i kod drugih podtipova limfoma kao sto je limfom marginalne zone, mantle celijski limfom, Hockinova bolest, a uvode se indikacije i za pojedine sistemske bolesti vezivnog tkiva, kao sto je reumatoidni artritis.

Mihaljević, Biljana; Jaković, Ljubomir; Janković, Snežana; Peruničić-Jovanović, Maja; Milošević, Violeta; Anđelić, Boško; Sretenović, Aleksandra; Petrović, Milan - Mediastinal lymphomas: Differential diagnosis - Vojnosanitetski pregled