IN VITRO DRUG RESISTANCE IN CHILDHOOD MATURE B-CELL ACUTE LYMPHOBLASTIC LEUKEMIA

Background. Mature B-cell acute lymphoblastic leukemia (B-ALL) is a rare type of leukemia in children and counts for 1-2% of all leukemia cases. Pediatric B-ALL is treated according to protocols for non-Hodgkin lymphomas. Objective. The aim of the study was to analyze the in vitro drug resistance in children with B-ALL compared to ALL with other phenotypes. Material and methods. A total number of 15 children with B-ALL (6 girls and 9 boys, median age 8 years, range 1.9-15 years) were included into the analysis. The in vitro drug resistance tests on leukemic cells were performed by means of the MTT assay. The results of B-ALL patients were compared to those obtained in patients with pre- B/common ALL (479 cases), pro-B-ALL (31cases) and T-ALL (87 cases). Results: B-ALL cells were more resistant than pre-B/common-ALL cells to dexamethasone and idarubicin. In comparison to pro-B-ALL phenotype, B-ALL blasts were more resistant to idarubicin and more sensitive to treosulfan. No significant differences were found in the in vitro drug resistance between B-ALL and T-ALL. Blasts of T-ALL were more resistant than pre-B/common-ALL cells to most of tested drugs. Conclusion: From the clinical point of view, B-ALL cells have similar in vitro drug sensitivity when compared to T-ALL, and higher drug resistance to dexamethasone than pre-B/common-ALL.Pomimo znacznej liczby publikacji poświęconych oporności in vitro na cytostatyki u dzieci z ostrymi białaczkami, brakuje jakichkolwiek danych o komórkach ostrej białaczki limfoblastycznej z dojrzałych limfocytów B. Jest to najrzadsza postać ostrej białaczki limfoblastycznej u dzieci i obejmuje ok. 1-2% wszystkich rozpoznań. Białaczkę tę jest leczy się według odrębnych protokołów, wspólnych dla B-ALL i B-NHL. C e l e m p r a c y była analiza oporności in vitro na cytostatyki w B-ALL w porównaniu z komórkami ALL o innych fenotypach: pro-B ALL, pre-B/common ALL i TALL. Do badania włączono 15 pacjentów (6 dziewczynek i 9 chłopców, mediana wieku 8 lat, zakres od 1,9 do 15 lat) z ALL z dojrzałych limfocytów B. Wyniki oporności in vitro porównywano z komórkami chorych z pre-B/common ALL (479 chorych), pro-B ALL (31 chorych) i T-ALL (87 pacjentów). Badania prowadzono w warunkach in vitro z wykorzystaniem komórek białaczkowych pobranych i wyizolowanych od pacjenta ze szpiku kostnego i/lub krwi obwodowej w momencie rozpoznania białaczki. Badania wrażliwości i oporności na leki przeprowadzono za pomocą testu MTT. Blasty B-ALL były bardziej oporne niż blasty pre-B/common ALL na deksametazon i idarubicynę. Komórki B-ALL w porównaniu z blastami pro-B ALL bardziej oporne na idarubicynę i bardziej wrażliwe na treosulfan. Pomiędzy komórkami B-ALL i T-ALL nie stwierdzono różnic w zakresie oporności na badane leki. Dzięki przeprowadzonym badaniom poszerza się wiedza o dziecięcej B-ALL. Być może w protokołach terapeutycznych znajdą zastosowanie leki, dla których wykazano największą wrażliwość in vitro komórek B-ALL, na przykład treosulfan

OPORNOŚĆ IN VITRO NA CYTOSTATYKI W OSTREJ BIAŁACZCE LIMFOBLASTYCZNEJ B-KOMÓRKOWEJ U DZIECI

B a c k g r o u n d . Mature B-cell acute lymphoblastic leukemia (B-ALL) is a rare type of leukemia in children and counts for 1-2% of all leukemia cases. Pediatric B-ALL is treated according to protocols for non-Hodgkin lymphomas. O b j e c t i v e . The aim of the study was to analyze the in vitro drug resistance in children with B-ALL compared to ALL with other phenotypes. M a t e r i a l a n d m e t h o d s . A total number of 15 children with B-ALL (6 girls and 9 boys, median age 8 years, range 1.9-15 years) were included into the analysis. The in vitro drug resistance tests on leukemic cells were performed by means of the MTT assay. The results of B-ALL patients were compared to those obtained in patients with pre- B/common ALL (479 cases), pro-B-ALL (31cases) and T-ALL (87 cases). Results: B-ALL cells were more resistant than pre-B/common-ALL cells to dexamethasone and idarubicin. In comparison to pro-B-ALL phenotype, B-ALL blasts were more resistant to idarubicin and more sensitive to treosulfan. No significant differences were found in the in vitro drug resistance between B-ALL and T-ALL. Blasts of T-ALL were more resistant than pre-B/common-ALL cells to most of tested drugs. Conclusion: From the clinical point of view, B-ALL cells have similar in vitro drug sensitivity when compared to T-ALL, and higher drug resistance to dexamethasone than pre-B/common-ALL.Pomimo znacznej liczby publikacji poświęconych oporności in vitro na cytostatyki u dzieci z ostrymi białaczkami, brakuje jakichkolwiek danych o komórkach ostrej białaczki limfoblastycznej z dojrzałych limfocytów B. Jest to najrzadsza postać ostrej białaczki limfoblastycznej u dzieci i obejmuje ok. 1-2% wszystkich rozpoznań. Białaczkę tę jest leczy się według odrębnych protokołów, wspólnych dla B-ALL i B-NHL. C e l e m p r a c y była analiza oporności in vitro na cytostatyki w B-ALL w porównaniu z komórkami ALL o innych fenotypach: pro-B ALL, pre-B/common ALL i TALL. Do badania włączono 15 pacjentów (6 dziewczynek i 9 chłopców, mediana wieku 8 lat, zakres od 1,9 do 15 lat) z ALL z dojrzałych limfocytów B. Wyniki oporności in vitro porównywano z komórkami chorych z pre-B/common ALL (479 chorych), pro-B ALL (31 chorych) i T-ALL (87 pacjentów). Badania prowadzono w warunkach in vitro z wykorzystaniem komórek białaczkowych pobranych i wyizolowanych od pacjenta ze szpiku kostnego i/lub krwi obwodowej w momencie rozpoznania białaczki. Badania wrażliwości i oporności na leki przeprowadzono za pomocą testu MTT. Blasty B-ALL były bardziej oporne niż blasty pre-B/common ALL na deksametazon i idarubicynę. Komórki B-ALL w porównaniu z blastami pro-B ALL bardziej oporne na idarubicynę i bardziej wrażliwe na treosulfan. Pomiędzy komórkami B-ALL i T-ALL nie stwierdzono różnic w zakresie oporności na badane leki. Dzięki przeprowadzonym badaniom poszerza się wiedza o dziecięcej B-ALL. Być może w protokołach terapeutycznych znajdą zastosowanie leki, dla których wykazano największą wrażliwość in vitro komórek B-ALL, na przykład treosulfan

Dyskwalifikacja dawcy komórek krwiotwórczych w trakcie chemioterapii wysokodawkowanej u biorcy przygotowywanego do transplantacji: propozycja algorytmu postępowania ratunkowego

BackgroundA donor hematopoietic cells disqualification is an uncomfortable situation at each stage of the donor typing and qualification because of extended waiting time to transplant. The occurrence of such an event occurring after completed conditioning is a life-threatening situation for the patient. We present a case report where the donor was disqualified during conditioning of the patient.Case reportA 17-year-old girl suffering from secondary AML was referred to HSCT unit for a transplant from matched unrelated donor. Conditioning consisted of busulfan, melfalan, fludarabine, and anti-thymocyte globulin (ATG Genzyme). After 4 days of chemotherapy, an information has been received about severe adverse event during mobilization of peripheral blood stem cells (PBSC) at the donor and the lack of her agreement to harvest bone marrow. Hence there was a necessity to cancel the procedure of PBSC mobilization and apheresis.Rescue proceduresFollowing rescue procedures have been undertaken immediately: (1) cessation of conditioning; (2) an urgent new search for another unrelated donor; and (3) arrangement for a rescue haploidentical transplant from mother, who was qualified for the procedure of PBSC mobilization.ResultsAs a consequence of undertaken steps a new mismatched unrelated (8/10) donor was found within 4 days. The patient continued chemotherapy and dosage of ATG has been increased by 50%. The PBSC apheresis process from haploidentical donor was cancelled. The transplantation was performed with a three-day delay in comparison to initially scheduled protocol.ConclusionWe believe that the proposed algorithm of rescue procedures can facilitate the proceedings in the case of donor hematopoietic cells disqualification directly prior to transplantation. It seems reasonable to propose a discussion on the implementation of procedures to reduce the risk of similar events. To consider is typing for each patient two potential donors, collection of material for transplantation before proceeding to transplantation and collection from each patient's own material for transplantation to the rescue

Znaczenie prognostyczne rearanżacji BCR-ABL w ostrej białaczce limfoblastycznej u dzieci

B a c k g r o u n d . Acute lymphoblastic leukemia (ALL) is the most frequent pediatric malignancy. Presence of adverse risk factors determines risk group stratification in this disease.O b j e c t i v e . The aim of study was the analysis of results of therapy and role of prognostic risk factors in treatment of childhood ALL in kujawsko-pomorskie region in 1995-2010.P a t i e n t s a n d m e t h o d s . During this period, ALL was diagnosed in 223 patients. With respect to time period and therapy protocol, the patients were divided into two groups: group 1 A/B (1995-2002) and group 2 (2002- 2010). Probability of overall survival (OS), event-free survival (EFS) and relapse-free survival (RFS) were analyzed. Uni- and multivariate analyzes for risk factors were performed.R e s u l t s . Over the analyzed 17-year period, OS has increased from 77.9% in group 1A and 73.7% in group 1B to 86.2% in group 2. Results of RFS and EFS have also increased during this time. The death rate has decreased from 26% in group 1A and 26.3% in group 1B to 10.2% in group 2. The most important adverse prognostic risk factors during the first period included involvement of liver, spleen, lymph nodes as well as poor response to initial therapy, while during the second period the most important independent risk factor was BCR-ABL rearrangement in lymphoblasts.C o n c l u s i o n s . The most important independent prognostic risk factors in pediatric ALL include advanced disease, BCR-ABL rearrangement, and initial response to therapy. These factors are used for stratification to treatment groups, intensification of therapy and hematopoietic stem cell transplantation.W s t ę p . Ostra białaczka limfoblastyczna (ALL) jest najczęstszym nowotworem wieku dziecięcego. W tej chorobie obecność czynników ryzyka decyduje o stratyfikacji pacjentów do grup ryzyka.C e l p r a c y . Analiza wyników terapii i roli czynników prognostycznych w ALL u dzieci w regionie kujawsko-pomorskim w latach 1995-2010.P a c j e n c i  i  m e t o d y k a . Analizą objęto 223 dzieci, które podzielono na 2 grupy w zależności od okresu terapii i stosowanych protokołów leczenia: grupa 1A/B (1995-2002) i grupa 2 (2002-2010). Wyznaczono prawdopodobieństwo przeżycia wolnego od zdarzeń (pEFS), prawdopodobieństwo przeżycia (pOS) i prawdopodobieństwa przeżycia wolnego od wznowy (pRFS). Przeprowadzono analizę jedno- i wielowariantową czynników ryzyka niepowodzenia terapii.Wy n i k i . W analizowanym okresie 17 lat, OS wzrosło od 77,9% w grupie 1A i 73,7% w grupie 1B do 86,2% w grupie 2. Wyniki RFS i EFS również uległy poprawie. W tym czasie odsetek zgonów obniżył się z 26% w grupie 1A i 26,3% w grupie 1B do 10,2% w grupie 2. W analizie czynników ryzyka wykazano, że w pierwszym analizowanym okresie zajęcie wątroby, śledziony i węzłów chłonnych oraz niekorzystna początkowa odpowiedź na terapię były związane z gorszymi ostatecznymi wynikami terapii, natomiast w drugim okresie czasu najsilniejszym niezależnym niekorzystnym czynnikiem rokowniczym była obecność rearanżacji BCR-ABL w limfoblastach.Wn i o s k i . Najważniejszymi czynnikami prognostycznymi w ALL u dzieci są: zaawansowanie choroby, odpowiedź na leczenie oraz obecność rearanżacji BCR-ABL, które są podstawą stratyfikacji do grup ryzyka, intensyfikacji leczenia w grupach wysokiego ryzyka oraz kwalifikacji do przeszczepiania komórek krwiotwórczych

Prognostic significance of BCR-ABL rearrangement in childhood acute lymphoblastic leukemia

B a c k g r o u n d. Acute lymphoblastic leukemia (ALL) is the most frequent pediatric malignancy. Presence of adverse risk factors determines risk group stratification in this disease. O b j e c t i v e. The aim of study was the analysis of results of therapy and role of prognostic risk factors in treatment of childhood ALL in kujawsko-pomorskie region in 1995-2010. P a t i e n t s a n d m e t h o d s. During this period, ALL was diagnosed in 223 patients. With respect to time period and therapy protocol, the patients were divided into two groups: group 1 A/B (1995-2002) and group 2 (2002- 2010). Probability of overall survival (OS), event-free survival (EFS) and relapse-free survival (RFS) were analyzed. Uni- and multivariate analyzes for risk factors were performed. R e s u l t s. Over the analyzed 17-year period, OS has increased from 77.9% in group 1A and 73.7% in group 1B to 86.2% in group 2. Results of RFS and EFS have also increased during this time. The death rate has decreased from 26% in group 1A and 26.3% in group 1B to 10.2% in group 2. The most important adverse prognostic risk factors during the first period included involvement of liver, spleen, lymph nodes as well as poor response to initial therapy, while during the second period the most important independent risk factor was BCR-ABL rearrangement in lymphoblasts. C o n c l u s i o n s. The most important independent prognostic risk factors in pediatric ALL include advanced disease, BCR-ABL rearrangement, and initial response to therapy. These factors are used for stratification to treatment groups, intensification of therapy and hematopoietic stem cell transplantation.W s t ę p. Ostra białaczka limfoblastyczna (ALL) jest najczęstszym nowotworem wieku dziecięcego. W tej chorobie obecność czynników ryzyka decyduje o stratyfikacji pacjentów do grup ryzyka. C e l p r a c y. Analiza wyników terapii i roli czynników prognostycznych w ALL u dzieci w regionie kujawsko-pomorskim w latach 1995-2010. P a c j e n c i  i  m e t o d y k a. Analizą objęto 223 dzieci, które podzielono na 2 grupy w zależności od okresu terapii i stosowanych protokołów leczenia: grupa 1A/B (1995-2002) i grupa 2 (2002-2010). Wyznaczono prawdopodobieństwo przeżycia wolnego od zdarzeń (pEFS), prawdopodobieństwo przeżycia (pOS) i prawdopodobieństwa przeżycia wolnego od wznowy (pRFS). Przeprowadzono analizę jedno- i wielowariantową czynników ryzyka niepowodzenia terapii. Wy n i k i. W analizowanym okresie 17 lat, OS wzrosło od 77,9% w grupie 1A i 73,7% w grupie 1B do 86,2% w grupie 2. Wyniki RFS i EFS również uległy poprawie. W tym czasie odsetek zgonów obniżył się z 26% w grupie 1A i 26,3% w grupie 1B do 10,2% w grupie 2. W analizie czynników ryzyka wykazano, że w pierwszym analizowanym okresie zajęcie wątroby, śledziony i węzłów chłonnych oraz niekorzystna początkowa odpowiedź na terapię były związane z gorszymi ostatecznymi wynikami terapii, natomiast w drugim okresie czasu najsilniejszym niezależnym niekorzystnym czynnikiem rokowniczym była obecność rearanżacji BCR-ABL w limfoblastach. Wn i o s k i. Najważniejszymi czynnikami prognostycznymi w ALL u dzieci są: zaawansowanie choroby, odpowiedź na leczenie oraz obecność rearanżacji BCR-ABL, które są podstawą stratyfikacji do grup ryzyka, intensyfikacji leczenia w grupach wysokiego ryzyka oraz kwalifikacji do przeszczepiania komórek krwiotwórczych

Acute non-hematological toxicity of intensive chemotherapy of acute lymphoblastic leukemia in children

IntroductionLeukemia belong to 31% of all childhood malignancies. Acute lymphoblastic leukemia (ALL) is the most frequent type of pediatric leukemia accounting for 80–85% of all cases. Progress in diagnostics and therapy of leukemia is dependent on international cooperation. The objective of the study was the analysis of non-hematological toxicity during intensive chemotherapy according to two consecutive intercontinental protocols. Patients and methodsA total number of 210 children diagnosed for ALL who were treated in single center between 2002 and 2018 were divided in two groups defined by therapeutic protocol: ALL IC-BFM 2002 (group 1) and ALL IC-BFM 2009 (group 2). Data were entered prospectively from 2002 into international ALL IC-BFM 2002 and ALL IC-BFM 2009 registry. Non-hematological toxicity was analyzed according to the criteria followed in protocols, compatible with CTCAE criteria. ResultsThe most frequent toxicities included hepatic toxicity with transaminitis and hyperbilirubinemia, infections, oral mucositis and gut toxicity with vomiting, and/or diarrhea. Non-hematological toxicity episodes calculated as a ratio per patient were comparably often observed in both the groups; however, the distribution was different. There were more grade III and less grade II toxicities. This was mainly related to significant increase in the rates of infections and transaminitis. However, there was a significant decrease in vomiting and central and peripheral neurotoxicity. ConclusionsIntensive treatment of ALL is burdened with frequent severe toxic and infectious complications. Further progress in therapy of pediatric ALL is dependent on sophisticated supportive therapy and very well experienced and knowledgeable therapeutic team

High risk of invasive fungal disease in children undergoing hematopoietic cell transplantation or complex anticancer therapy: the adverse role of post-transplant CMV replication

Introduction: We analyzed the epidemiology and outcomes of treatment of invasive fungal disease (IFD) in children during anticancer therapy (PHO, pediatric hematology and oncology) or after hematopoietic cell transplantation (HCT) over a period of eight consecutive years in a single-center study. Material and methods: Overall, a total of 254 HCTs were performed, and 415 children were newly diagnosed for malignancy. Incidence, epidemiology and outcome of IFD were analyzed. Results: The cumulative incidence of any IFD was 32.6% in allo-HCT, 22.2% in PHO, and 6.0% in auto-HCT patients. The incidence of proven +probable IFD was 12.6%, 10.4%, and 6.0%, respectively. As many as 77.0% HCT and 67.4% PHO of fungal episodes occurred in acute leukemia patients: the highest incidence of any IFD was observed for acute lymphoblastic leukemia (29.3% in HCT; 40.5% in PHO) and for acute myeloblastic leukemia (51.1% in HCT; 65.0% in PHO) patients. There were no significant differences in the incidence of fungal infections in both allo-HCT and PHO patients between the 2-year periods. Factors contributing to an increased risk of IFD in allo-HCT patients were: CMV replication, and acute and chronic graft-versus-host disease (GvHD). Survival from IFD was 91.9% in PHO, and 78.1% in HCT patients. Fungal pneumonia in HCT patients resolved in 62.9%, while in PHO patients it resolved in 93.5%. Conclusions: The risk of IFD in allo-HCT patients is much higher than in auto-HSCT and PHO patients. The outcome of IFD is better in PHO and auto-HCT than in allo-HCT settings

Changing risk factors in childhood acute lymphoblastic leukemia: experience from Kujawsko-Pomorski region 1976–2018

Introduction: Acute lymphoblastic leukemia (ALL) is the most common malignancy in children. Risk factors in childhood ALL have changed during recent decades, mostly due to treatment personalization. The aim of this study was to analyze therapy results and prognostic factors in childhood ALL in the Kujawsko-Pomorski region of Poland between 1976 and 2018. Material and methods: Data from 495 patients (0–18 years old) diagnosed with ALL from the Kujawsko-Pomorski region between 1976 and 2018 was analyzed. Prognostic factors were analyzed separately in specific therapeutic groups, which were defined by several therapy protocols. Results: Prognostic factors have changed over the course of consecutive therapeutic periods. Between 1976 and 1988 (the first and second therapeutic protocols), central nervous system involvement was the most important risk factor. During the third therapeutic period, an unsatisfactory treatment response on days 8 and 14 was related to a poor outcome. In 1995–2002, the risk factors were hepatomegaly, splenomegaly, lymph nodes involvement, and unsatisfactory therapy response on days 15 and 33. Between 2002 and 2011, immunophenotype other than ‘common’ and hemoglobin level at diagnosis were the risk factors, and a lack of BCR-ABL aberration was related to better therapy results. During the final analyzed period (2011–2018), failure to achieve remission on day 33 was a risk factor, and patients classified as non-high risk group and those aged <6 years had better outcomes. Conclusions: The changing profile of risk factors in ALL has reflected progress in ALL therapy, with the gradual elimination of factors related to poor outcomes, mostly due to modifications in treatment and the development of diagnostic methods as well as therapy monitoring

Relapsed childhood acute myeloid leukemia: prognostic factors and outcomes: experience from a single oncology center

Introduction: Over recent decades, significant progress in the treatment of childhood acute myeloid leukemia (AML) has been made. However, the relapsed disease remains a challenge. The aim of this study was to analyze therapy results in pediatric patients treated for relapsed AML in a single oncology center, with a particular focus on prognostic factors. Materials and methods: Data from patients younger than 19 years with AML diagnosed between January 1994 and December 2020 treated in the Department of Pediatric Hematology and Oncology in Bydgoszcz, Poland was analyzed, with detailed analysis of patients with relapsed disease. Results: A total of 77 children were diagnosed with AML in the analyzed period and 21 had a relapsed disease (27.3%). Bone marrow relapse was the most common. The risk factors of relapse included white blood cells >100 G/L at initial diagnosis and classification to the high risk group. Late relapse was related to poorer outcomes. The 5-year probability of overall survival for the entire group was 28.6%, and this was significantly higher in patients who achieved second remission compared to those who did not (44.9% vs. 0.0%, p <0.001). The main reason for death was progression of disease, which occurred in 10 patients. Conclusions: Outcomes in relapsed AML in children are still dismal. Lack of second remission suggests the need for experimental therapy