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Biomedical subjects

W Balwierz

Publications and source records attributed to W Balwierz.

At least 19 recordsLinked to original sources
PubMed2005

Twenty years of Polish experience with three consecutive protocols for treatment of childhood acute myelogenous leukemia.

Until 1983, results of treatment of acute myelogenous leukemia (AML) in Poland with different regimens were very poor. In 1983, the Polish Pediatric Leukemia/Lymphoma Study Group introduced a unified treatment protocol--a modified version of BFM-83 protocol. This led to an increase in the curability of AML from 15% to approximately 32%. In 1994, a modification was made: the high-risk patients (>5% blasts in bone marrow on day 15 of therapy and all M5 cases) received two additional cycles with intermediate-dose cytarabine (ID-ARAC). This led to a nonsignificant improvement in the 5-year event-free survival (EFS) rate from 32 to 36%. A new treatment protocol employing idarubicin in place of daunorubicin was introduced in 1998 and produced better initial responses, increase in the number of patients attaining remission after induction therapy and proportional increase of standard-risk patients. The probability of 5-year EFS (pEFS) for the whole group of patients increased from 36 to 47%. In standard- and high-risk groups, the 5-year pEFS was 62 and 33%, respectively. The probability of 5-year disease-free survival was 58% in the whole group, and there were no differences between risk groups. Unsatisfactory treatment results in children classified into the high-risk group are principally due to the low remission rate.

Acute Disease↗
PubMed2005

In vitro sensitivity of leukemic cells to nucleoside derivatives in childhood acute leukemias: good activity in leukemic relapses.

Nucleoside analogues such as fludarabine and cladribine are used in therapy of indolent lymphomas and leukemias in adults, while cytarabine is used mainly in protocols for acute leukemias. Mechanisms of their activity is based on inhibition of enzymes involved in DNA, RNA and protein synthesis. The objective of the study was the analysis of in vitro cellular drug sensitivity in childhood acute lymphoblastic (ALL) and myeloid (AML) leukemia. Isolated leukemic cells obtained from 264 patients, including 152 initial ALL, 45 relapsed ALL, 54 initial AML and 13 relapsed AML were tested for cytotoxicity for fludarabine, cladribine, and cytarabine by the MTT assay. Drug concentration lethal to 50% of tested cells was regarded as a value of drug resistance. Three tested nucleoside analogues showed highest cytotoxicity against initial ALL samples. Samples of relapsed ALL and initial AML were more resistant than ALL de novo ones. Unexpectedly, no differences were observed between initial and relapsed AML samples for all tested drugs, what suggests that nucleoside analogues are active drugs in relapsed AML, which is commonly regarded as a resistant disease. All tested drugs presented significant cross-resistance in each of analyzed subgroups. In summary, tested nucleoside analogues presented relatively good activity against childhood leukemias at relapse stage.

Adolescent↗
PubMed2004

Remaining problems and controversies in the management of childhood head and neck soft tissue sarcomas: Retrospective (national) Multicenter Study of the Polish Pediatric Solid Tumors Group.

Soft tissue sarcomas in children are a heterogeneous group of malignant diseases. Among these, tumors localized in the head and neck region are especially difficult to treat. While multidisciplinary care has dramatically improved the prognosis of sarcoma patients, their treatment remains uncertain because of demand on radical surgical resection of the tumor. Achieving cure without deforming or mutilating the child remains the primary goal of treatment. This study is the multicenter (nationwide, 11 Polish centers) retrospective analysis of the treatment results in children having soft tissue sarcoma in the head and neck region during the previous decade (from 1991 to 2001). Late effects of the treatment are documented in long-term survivals. Eighty-five children from 1 to 212 months of age were included. Different multimodal treatment protocols were utilized (CWS-91, SIOP-MMT-91, and CWS-96). The median observation time was 25 months. Data on long-term effects were collected in 34 long-term survivals. Complete remission was achieved in 68 (80%) patients. Primary treatment failure occurred in 13 (15.3%) patients, all of whom succumbed in disease progression. Relapse occurred in 21 (30.9%) patients primarily achieving complete remission. Second primary neoplasm occurred in 3 children. The estimated 5-year event-free survival and the 5-year total survival rates for the whole group are 0.38 and 0.55, respectively. The main late effect documented in long-term survivals were cosmetic defects in 12 (35.3%) and visual field deficit or blindness in 8 (26.5%). Despite substantial improvement of the prognosis of pediatric soft tissue sarcomas, the multimodal treatment of head and neck region tumors remains controversial. Improved long-term outcome and focusing on psychosocial difficulties raise the important and difficult problem of functional results and cosmesis. Tumors localized in the orbit carry an excellent prognosis. However, the main late sequela is vision impairment and cosmetic defect due to the therapy given many years earlier. Two other tumor localizations--the parameningeal and nonparameningeal ones--still have bad prognosis. The observations made in this study confirm that main prognostic factors are the size of the primary tumor and the tumor stage. The worst prognosis remains invasive tumor (T2-stage) with a size over 5 cm. Individually adjusted multimodal therapy, which imperatively needs to be radical, though not mutilating, might minimize the late effects. Psychosocial problems in long-term survivors need to be focused on at the national level and better support must be provided in the future, involving a team of different medical and paramedical profiles.

Adolescent↗
PubMed2002

Dexrazoxane has no impact on sensitivity of childhood leukemic blasts to daunorubicin.

Dexrazoxane (DEX) prevents the formation of free radical, lipid peroxidation and cardiotoxicity caused by anthracyclines. Due to a concern about its possible interference with anthracyclin cytotoxicity, the in vitro effect of DEX on daunorubicin (DNR) cytotoxicity, cell cycle and induction of apoptosis by annexin-V was investigated. The sensitivity to DEX, DNR and their combination was tested by the MTT assay in human promyelocytic leukemia HL-60, the erythroid blast crisis CML K562 cell lines and in 45 children with ALL and AML. Cell cycle analysis and annexin-V expression were performed by flow cytometry. It has been observed that DEX itself weakly, but significantly caused cytotoxicity in both cell lines and in patient samples, especially in initial ALL samples. DEX sensitized K562 and HL60, but not patient samples, to cytotoxicity of DNR. The percentage of necrotic/apoptotic cells, as detected in cell cycle analysis and annexin V staining, was higher after exposure to DEX +/- DNR, when compared to respective samples not treated with DEX, in both cell lines but not in patient samples. Expression of annexin V induced by DEX in both cell lines was enlarged, regardless of the presence of DNR. This difference was not observed in patient samples, however, the number of cells expressing annexin V was higher after exposure to DEX +/- DNR in comparison to respective samples not treated with DEX. In conclusion, it seems that DEX possibly has no impact on the sensitivity of childhood leukemic blasts to DNR, however, has weak cytotoxic properties itself.

Adolescent↗
PubMed2002

In vitro comparative antileukemic activity of various glucocorticoids in childhood acute leukemia.

Resistance to glucocorticoids is nowadays one of the strongest adverse risk factors in the treatment of childhood acute lymphoblastic leukemia (ALL). Differential in vitro antileukemic activity of various glucocorticoids and their cross-resistance pattern in childhood acute lymphoblastic and myeloblastic leukemia was determined by means of the MTT assay in 49 successfully tested samples of childhood acute leukemia. The equivalent antileukemic concentrations of respective drugs against lymphoblasts in de novo ALL samples were: 35 microM of hydrocortisone; 8 microM of prednisolone; 1.6 microM of methylprednisolone; 0.47 microM of dexamethasone and 0.23 microM of betamethasone. In comparison to initial ALL samples, the group of relapsed ALL was more resistant to: prednisolone (38-fold, p=0.004), dexamethasone (>32-fold, p=0.004), methylprednisolone (37-fold, p=0.039), betamethasone (38-fold, p=0.018) and hydrocortisone (33-fold, p=0.030). The group of acute myeloid leukemia (AML) samples were resistant to: prednisolone (>83-fold, p<0.001), dexamethasone (>32-fold, p<0.004), methylprednisolone (>65-fold, p=0.003), betamethasone (>66-fold, p=0.004) and hydrocortisone (61-fold, p=0.007), when compared to ALL at presentation. A significant cross-resistance between all used glucocorticoids as well as between glucocorticoids and other tested anti-leukemic drugs was found. In some individual cases in vitro glucocorticoid cross-resistance was less pronounced and relatively good antileukemic activity of betamethasone was observed.

Antineoplastic Agents↗
PubMed2001

Induction of apoptosis and bcl-2 expression in acute lymphoblastic leukaemia and non-Hodgkin's lymphoma in children.

bcl-2 expression is associated with the expression of the multidrug resistance molecule (p-gp) and the resistance of leukaemia cells to the induction of apoptosis. The activity of p-gp is the main mechanism of resistance of leukaemia cells to chemotherapy. This study assessed the induction of apoptosis of acute lymphoblastic leukaemia (ALL) and non-Hodgkin's lymphoma (NHL) blastic cells following in vitro treatment with dexamethasone (DXM), vincristine (VCR), and tumour necrosis factor (TNF) in relation to the expression of bcl-2 and p-gp. Common ALL (cALL; n = 24 patients), common ALL with co-expression of myeloid antigens (cALL + My; n = 9), ALL-T (n = 9), and NHL [n = 6 (T type, n = 2; B type, n = 4)] were included. The expression of bcl-2 and p-gp and apoptosis were assayed by flow cytometry. Spontaneous apoptosis was low (< 5%) in cALL and ALL-T and higher (> 8%) in NHL and cALL + My. A high frequency of bcl-2 expression was noted in cALL and cALL + My. A high frequency of p-gp expression was observed in cALL + My, ALL-T, and NHL. There was a reverse association between bcl-2 expression and spontaneous apoptosis. DXM-induced apoptosis was observed in 52.63%, TNF-induced in 42.85%, VCR-induced in 36.36%, and GM-CSF-induced in 33.3% of leukaemia and lymphoma cases. DXM and GM-CSF-driven apoptosis was reversibly associated with bcl-2-expression (bcl-2-dependent mechanism). VCR and TNF-driven apoptosis was not associated with bcl-2 expression, suggesting a different, bcl-2-independent, mechanism(s) of its induction. The in vitro induction of apoptosis was not associated with expression of p-gp.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2001

Expression of CD20 on acute lymphoblastic leukemia cells in children.

CD20 determinant expressed on B precursors is associated with regulation of proliferation, apoptosis and maturation of these cells. The acute lymphoblastic leukemia "common" type (cALL) based on expression of CD20 is subdivided in type I and II. However, the clinical significance of CD20 expression on cALL and significance of cALL type I and II discernment are not fully elucidated. The association of CD20 expression with the expression of multidrug resistance molecule (MDR), CD34, atypical immunophenotypes of leukemia cells and response to induction therapy were determined in the group of 147 patients with acute lymphoblastic leukemia (ALL) B progenitor type (ALL-proB -14 patients) and common type (cALL-133 patients). The expression of CD20 on leukemia cells was studied routinely at diagnosis before the therapy. This expression was noted on leukemia cells of 6 ALL-proB patients (42.8%) and 66 cALL patients (49.6%). The expression of CD20 showed no association with the expression of CD34, CD22 and MDR. The reverse association was observed between CD20 expression and the presence of co-expression of myeloid (CD13, CD33, CD65, CD15) and T lymphoid determinants (CD2, CD5, CD7) on leukemia cells. The effect of induction therapy analyzed as time of blast cells cytoreduction in peripheral blood and time of reaching the complete remission showed the slower clearance of peripheral blood from blast cells associated with expression of CD20. There was no association of CD20 expression with the time of reaching the hematological remission. The above results suggested a "protective" role of CD20 against co-expression of other determinants (myeloid and lymphoid) and no association with the results of induction therapy.

Adolescent↗
PubMed2001

[Evaluation of growth and body weight in children and adolescent during and after treatment of acute lymphoblastic leukemia].

The aim of the study was to estimate growth curve and body mass during and after a treatment of ALL. Retrospective study group included 48 children (27 boys and 21 girls). The age at the start of the treatment varied from 1.4 up 17 years, during our evaluation 4.6-25.4 years. Patients were treated according to modified American (New York Protocol) and German (BFM) protocols. 43 children received central nervous system radiation in a dose of 14-24 Gy. All children completed the treatment protocol and are in the remission. Growth velocity and body mass were estimated during and after the ALL treatment. During the treatment growth retardation was observed at 34 children (2/3 patients). No significant difference in growth velocity was found between group of standard and high risk of ALL. Combined radiotherapy and chemotherapy has probably more influence for growth retardation than chemotherapy alone. Obesity was stated at 13 patients (27%), mostly boys. After the treatment 9 children were permanently obese. Body mass deficiency was found at 5 patients during the treatment and was the same when the treatment protocol was completed.

English Abstract↗
PubMed2000

Incidental neuroblastoma.

The diagnosis of neuroblastoma in its early stage, especially in asymptomatic children, with the so-called incidentally diagnosed disease, may be associated with a good prognosis. The aim of this study is an attempt at analyzing this problem. Between 1 January 1993 and 30 April 1998, 40 children with newly diagnosed neuroblastoma started therapy at the authors' department. The disease was diagnosed incidentally in 5 (12.5%) patients. In no incidentally diagnosed child was stage IV disease detected, while in the remaining patients its incidence was 71%. All the children (median age 2 months) with incidental diagnosis have remained alive (median 39 months) in continuous remission without treatment. Among 35 children (median age 2 years and 7 months) with overt neuroblastoma, 18 died (median survival time 14.5 months). Seventeen patients have remained alive (median 45 months). The results show that children with incidentally diagnosed neuroblastoma are characterized by a more favorable prognosis than children with clinical disease.

Humans↗
PubMed2000

[Polish Paediatric Leukaemia/Lymphoma Study Group - 25 years of activity].

In 1974, Professor Jerzy Armata initiated the organization of a multicentre cooperative group, which later became known as the Polish Paediatric Leukaemia/Lymphoma Study Group (PPL/LSG). At first the Group included three centres headed by Professor J. Armata (Cracow), Professor U. Radwanska (Poznan) and Professor J. Boguslawska-Jaworska (Wroclaw), but gradually it extended to nine university departments of paediatric hematologic oncology. Within the past 25 years, the introduction and employment of standardized, common treatment regimens based on our experience, as well as on the results of other oncological groups in Europe and the United States, resulted in a significant improvement of therapeutic results in childhood cancer, especially of the lymphatic and haematopoetic systems. The improvement in the recovery rates was as follows: in acute lymphoblastic leukaemia: from 25% to 84%, in non-Hodgkin's lymphoma recovery: from 28% to 82%, in Hodgkin's disease: from 80% to 90%. In acute non-lymphoblastic leukaemia the improvement in treatment results (from 15% to 40%) was also significant but still unsatisfactory.

Child↗
PubMed2000

[Intermediate doses of cytosine arabinoside in the treatment of acute non-lymphoblastic leukaemia in children].

Between 1995-1997, at 7 centres of the Polish Paediatric Leukaemia/Lymphoma Study Group (PPLLSG) treatment was started in 102 children with acute non-lymphoblastic leukaemia. Sixty-two children treated according to the new protocol adjusted for risk factors were evaluated. Thirty-one patients belonged to standard risk and 23 to high risk group. Eight children were not evaluated due to early death. Out of 62 children, 44 (70,9%) achieved remission; in standard and high risk groups the rates of remission were 87,5% and 73%, respectively. Four-year event-free survival (EFS), relapse-free survival (RFS) and overall survival (OS) probability in all patients were: 40,2%, 42% and 59% respectively, in standard risk group: 49,5%, 52,5%, 59,1%; in high risk group: 42%, 43,4% and 57,8%. In comparison with the previous period (1983-1994) EFS increased from 30% to 42%, which was statistically insignificant.

Adolescent↗
PubMed2000

[Preliminary results of BFM 96 protocol in treatment of childhood ALL relapse in the experience of the Polish Paediatric Leukaemia /Lymphoma Study Group].

Between 1998 and 1999, 36 children aged from 3 months to 18 years (10 girls and 26 boys) with first relapse of acute lymphoblastic leukaemia were included in the study. The children were treated according to the BFM 96 relapse protocol. There were 24 cases with early (including 9 children with very early) and 12 cases with late relapse ( BM-20, local extra BM-6, combined 10). The overall second complete remission (CR) rate was 83,33%. The probability of overall EFS after 2 years was 73,3%. The results obtained with BFM 96 chemotherapy in children with first late relapse are acceptable. For children with early relapses, megachemotherapy with BMT in second remission should be used.

Adolescent↗
PubMed2000

[Adverse reactions associated with the use of L-asparaginase during therapy of patients with nB non-Hodgkin's lymphoma. Report of the Polish Paediatric LeuKaemia/Lymphoma Study Group].

The aim of the study was to determine the side effects of asparaginase administration during treatment protocol for childhood non-Hodgkin's lymphoma (NHL). Drug adverse reactions occurred in 20/66 of patients (30,3%) treated in 9 centres in Poland between 1993 and 1998. The most common side effects were coagulation disturbances in 12/66 of the children (18,2%), which occurred due to reduced production of important coagulation factors. Six patients (9,1%) developed impairment of liver function (9,1%). Drug toxicity caused the modifications of treatment protocol in 12/66 (18,2%) of patients, mainly in the induction phase; 3 children died due to relapse of disease.

Adolescent↗
PubMed2000

[The incidence and treatment of the first relapse in children with Hodgkin's disease].

From January 1988, to December 1997, among 447 children with Hodgkin's disease (HD) who underwent initial treatment in seven centres of the Polish Paediatric Leukaemia/Lymphoma Study Group, 442 patients obtained a complete remission (CR). The initial treatment consisted of multidrug chemotherapy (B-DOPA and MVPP) combined with local radiotherapy. Relapses occurred in 35 cases (7,9%). Two patients from other centres were also included in this analysis. Four patients were lost to follow-up; 33 patients with relapses were analysed. Early relapses (first complete remission (CR) shorter than 12 months) occurred in 17 cases. Treatment of the first relapse consisted of different types of multidrug chemotherapy. Six patients underwent high-dose chemotherapy and peripheral blood stem cells transplantation. Radiotherapy was used in 19 children. Second CR was achieved in 28 patients (85%). In 10 children (36%) second relapse occurred after 4 to 21 months (median = 10). In 17 cases the second CR lasted 12-14 (median=54) months. The probability of the 7-year freedom from second relapse was 64%. Eleven patients died; one of them in second CR due to toxic liver damage. Results of treatment in children with early relapses were significantly worse. In 17 patients with early relapse, and 16 children with late relapse, the second CR was achieved in 70% and 100% of cases, respectively. The probability of the 7-year overall survival, freedom from second relapse and event-free survival in children with early and late relapse was: 42, 58, 40%, and 94, 69, and 66%, respectively. The therapeutic results in the subgroups of children with relapses treated with different methods were not comparable because of the small number of children in each group. The use of multidrug chemotherapy with or without radiotherapy allows to achieve a long lasting second CR in more than 50% of children with HD who relapsed after initial combined modality treatment. The optimal treatment of relapsed HD in patients initially treated with multidrug chemotherapy with or without of radiotherapy, is currently unknown.

Adolescent↗
PubMed2000

[Results of the treatment of myelodysplastic syndrome (MDS)obtained by the Polish Paediatric Leukaemia /Lymphoma Study Group].

Sixty children with MDS treated in six centres of the Polish Paediatric Leukaemia/Lymphoma Study Group in the period 1975-1999 were included in the study. In 20 children RAEB-T, in 13 RA, in 21 RAEB and in 6 CMML were diagnosed. Our own and literature data showed that BMT is the best therapy for children with MDS. We need a new comprehensive protocol for the diagnosis and treatment of children with MDS in Poland.

Adolescent↗
PubMed2000

[G-CSF and GM-CSF in treatment of neutropaenia after chemotherapy in children with neoplasms].

A total number of 608 cycles of G-CSF and/or GM-CSF was applied in 280 patients aged from 6 months to 20 years during neutropaenia associated with chemotherapy of children's neoplasms (NHL-124, NBL-42, RMS-36, Nephroblastoma-18, Osteosarcoma-17, Ewing's Sarcoma-14, Hepatoblastoma-6, Neurofibrosarcoma-6, PNET-5, Medulloblastoma-3, Fibrohistiocytoma-3, Angiosarcoma-2, other - 4). G-CSF - Neupogen (Filgastrim, Hoffman La Roche - 492 cycles) and GM-CSF - Leucomax (Molgramostim, Shering Plough - 116 cycles) were administered 5 mg/kg/day s.c. Forty one children with malignancies (NHL -21 cases, solid tumours -17) treated before cytokines were in use served as a control group. Our study demonstrated that G-CSF and GM-CSF therapy, gives a shorter period of neutropaenia, reduction of the number of febrile days, decreased frequency of infection and shortened its duration.

Adolescent↗
PubMed1999

Childhood stage IV Hodgkin disease: therapeutic results of the Polish pediatric leukemia/lymphoma study group.

BACKGROUND: The therapeutic management in patients with stage IV Hodgkin disease is still controversial. PROCEDURE: Among 783 children with Hodgkin disease treated from 1971 to 1996, 56 patients (7.3%) were diagnosed with stage IV. The treatment consisted of MVPP or MVPP/B-DOPA chemotherapy combined with involved-field radiotherapy in 50 children. RESULTS: The results of treatment of stage IV patients were compared in the three sequential time periods, during which the therapy was modified. In these periods, the first complete remission was obtained in 67%, 86%, and 90% of children, respectively, and the 10-year event-free survival was 42%, 64%, and 85%, respectively. CONCLUSIONS: Alternate multidrug chemotherapy combined with low-dose involved-field radiotherapy is at present a satisfactory therapeutic method in children with stage IV Hodgkin disease.

Adolescent↗