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A Chybicka

Publications and source records attributed to A Chybicka.

At least 19 recordsLinked to original sources
PubMed2003

A prospective analysis of immune recovery in children following allogeneic transplantation of t-cell-depleted or non-T-cell-depleted hematopoietic cells from HLA-disparate family donors.

Transplantation of HLA-disparate hematopoietic stem cells from related donors is an alternative for the treatment of patients lacking an HLA-matched family or unrelated donor. In the cases of a single HLA antigen disparity, extensive T-cell depletion (TCD) is not required, yet antithymocyte globulin (ATG) must be administered to prevent GvHD or graft rejection. The major concern after HLA-mismatched transplants remains immune reconstitution. Therefore, we prospectively studied the recovery of lymphocyte subsets among 22 children transplanted from partially HLA-matched family donors. We compared two groups of patients: (1) the TCD group included children (n = 1.3) who received grafts after TCD (MACS) due to an HLA disparity for more than one antigen; (2) The non-TCD group included children with either one HLA-mismatched antigen, n = 7; or more than one disparate antigen (n = 2) who received T-cell-repleted grafts and ATG. The study demonstrated rapid NK cell reconstitution among the TCD group. TCD compromised T-cell reconstitution, thus preventing GvHD, but resulting in a higher incidence of severe infectious complications, graft rejection, and disease relapse. Increasing mixed chimerism required the application of donor T-cell addbacks, thus potentiating the risk of GvHD. Primary graft rejection occurred in eight children, who required further transplants. In the non-TCD group faster T-cell reconstitution (predominantly CD3+CD8+ cells) resulted in a lower rate of relapse and infection, yet a higher rate of GvHD, including two fatal cases. Due to improved immune reconstitution, in spite of an increased risk of GvHD, non-TCD transplants from single HLA-mismatched family donors remain a valuable option for children without matched donors.

Adolescent↗
PubMed2003

Clinical value of the flow cytometric method for measuring lymphocyte subset activation: spontaneous activation of T-cell subpopulations is associated with acute GvHD.

Thymidine ((3)H-TdR) incorporation remains the most commonly used method to quantifying T-cell proliferation. This method, however, does not provide information about specific lymphocyte subpopulations responding to different stimuli. In our study, we modified previously described nonradioactive flow-cytometric T-cell activation assay measuring the expression of a CD69+ antigen on T-cell subsets and applied it to analysis of lymphocyte subsets activation/proliferation in children after allogeneic hematopoietic cell transplantation (HCT). We compared the percentage of spontaneously activated lymphocyte subpopulations (background) and the percentage of PHA-P, PWM, and SEB-stimulated cell subsets from two groups of patients: group 1, children with Graft versus Host Disease (GvHD) and group 2, children without any signs of GvHD at the time of analysis. High rate of spontaneous T-cell subset activation was found in group 1 with CD3+CD8+Ts cells being the most affected cell population. High background activation of Th and B cells correlated with the occurrence of autoimmune phenomena posttransplant. Rapid quantification of CD69+ expression on unstimulated and stimulated T-cell subsets proved to be a valuable method for monitoring children after allogeneic HCT. High proportion of activated, unstimulated Ts cells observed in the GvHD group may underline the critical role of CD3+CD8+ cells in the pathogenesis of GvHD. Thus in future immunosuppressive therapy may be adjusted according to the proportion of activated Ts cells.

Bone Marrow Transplantation↗
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↗
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

[Results of treatment of children with chronic myelogenous leukaemia (CML) obtained by the Polish Paediatric Leukaemia/Lymphoma Study Group].

Retrospective analysis of 102 children with CML from 9 paediatric centres in Poland has been performed. A total number of 102 children: 58 boys and 44 girls aged 1-17 years (median 9.4 years old) with CML, treated in the period 1975-1999 were included in the study. Forty eight of 102 (47.1 %) children were treated with cytostatic drugs without IFN alpha: busulfan, hydroxyurea, 6-mercaptopurine or etoposide (VP-16). Fifty four of 102 (52.9%) patients were treated with interferon alpha (IFN alpha) after cytoreductive pretreatment. Thirty out of 102 (29.4%) patients underwent stem cell transplantation (SCT): 24 - matched related donor allo-BMT, 2 - matched unrelated donor allo-BMT, 1 - partially matched related donor T-cell depleted allo-PBPCT, 1 - syngeneic allo-BMT and 2 - autologous PBPCT. Overall survival analysis revealed that 46 of the 102 (45.1%) children remained alive: 5/35 (14.3%) children treated with cytostatics alone, 22/37 (59.5%) children treated with IFN alpha and 19/30 (63.3%) children treated with SCT. Among SCT survivors there are 10/17 (58.8%) children treated with IFN alpha prior to SCT and 9/13 (69.2%) children treated with cytostatics alone prior to SCT. The probability of 5-year survival is 0.51 in the group treated with SCT (median follow-up 58 months); 0.43 in the group treated with IFN alpha (median follow-up 53 months) and 0.23 in the group treated with cytostatics (median follow-up 31 months). Our data show, that BMT is the treatment of choice in CML in children. IFN alpha could be successfully applied as an alternative treatment for those, who do not have a suitable donor for allogeneic SCT. Better outcome in post BMT children, who were not treated with IFN alpha prior to SCT requires confirmation by studies on larger groups of patients. However, it seems to be justified to stop IFN alpha therapy at least 3 months before SCT. The main reason for unsuccessful treatment outcome in patients with CML in Poland remains the still insufficient access to MUD-BMT.

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

[Results of treatment of osteosarcoma in children according to the SFOP-94 protocol in the experience of the Polish Paediatric Solid Tumour Study Group].

Between April 1994 and December 1999, 34 children aged from 5 to 20 years (23 females and 11 males) suffering from osteosarcoma, were treated according to the SFOP-94 protocol. The primary preoperative chemotherapy consists of adriamycin and high-dose methotrexate administration. There were 28 patients with non-metastatic tumours of the extremities and 6 children presented disseminated disease with pulmonary metastases. The primary localization included femur - 20 patients, tibia - 9 patients and humerus - 5 patients. In 26 patients limb-salvage surgery was applied. The programme of chemotherapy was changed in 4 children because of toxicity of methotrexate (1 patient) and progression of disease (3 patients). 26 out of 34 (76,5 %) children are alive including 24 out of 28 patients with localized disease. EFS calculated according to Kaplan-Meier analysis was 60 % at 67 months.

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↗
PubMed1998

[The efficacy of BFM-90 program in the treatment of acute lymphoblastic leukemia in children in the studies of Polish pediatric leukemia/lymphoma group].

Between years 1993 and 1998, 113 children aged from 6 months to 18 years (41 girls and 72 boys) with first relapse of acute lymphoblastic leukaemia (ALL) were included in the study. All children were treated according to BFM-90 relapse protocol. Thirty-two cases were classified as very early relapses, 56 as early and 25 as late relapses. Sixty-one children had isolated bone marrow relapse, in 30 children extramedullary relapse occurred (in 21 children in central nervous system and in 16 children in testes). There were 23 combined relapses. Remission was achieved in 12 children with very early relapse (78.12%), 32 children with early relapse (85.71) and 19 children with late relapse (96%). Event-free survival in 30 months of follow-up was 29.2%, 59.0% and 73.2% for very early, early and late relapses, respectively. Sixteen children with relapsed ALL after chemotherapy according to BFM-90 relapse protocol underwent high-dose therapy with hematopoietic stem cell transplantation (in 3 cases autologous and in 13 cases allogeneic). In 6 children isolated bone marrow relapse occurred after transplantation, all of them died during subsequent chemotherapy. Ten children is alive and well from 2 to 43 months after transplantation. The results obtained with BFM-90 chemotherapy in children with first early relapses are not acceptable. Such patients require high-dose chemotherapy and transplantation of hematopoietic progenitor cells.

Adolescent↗
PubMed1998

[The analysis of failures in the treatment of children with chronic myelocytic leukemia in the studies of Polish pediatric leukemia/ lymphoma group].

94 children with chronic myelocytic leukaemia--CML treated in period 1975-1998 were included in the study. Twenty seven of 60 children were treated with hydroxyurea or busulfan with 6 MP. In 33 children aged 1, 5-17 years IFN (Interferon alfa) was applied at the dose of 3 millions units every second day subcutaneously. Our data showed that IFN alfa could be applied as an alternative treatment in children with CML, who have not a donor for allogenic BMT (bone marrow transplantation).

Adolescent↗
PubMed1998

[The analysis of failures in therapy of osteosarcoma in children treated according to SFOP-94 protocol in the studies of Polish pediatric solid tumors treatment group].

Between December 1989 and April 1998 twenty eight children aged from 5 to 20 years (18 female and 10 male) suffering from osteosarcoma were treated according to the OS-SFOP-94 protocol. Twenty four patients presented with localized tumor of extremities and four with pulmonary metastases. The majority of primary tumors exceeded 150 ml of volume. The primary preoperative chemotherapy consisted of adriamycin (70 mg/m2 every four weeks) and high-dose methotrexate (12 g/m2 every week). In 20 patients limb-salvage surgery was applied, in three children--amputation and in one child tibia resection with genu arthrodesis was applied. Five of 28 patients died, one because of treatment related infection, 2 non-responders with metastatic osteosarcoma due to progressive disease, and one because of local relapse with pulmonary metastasis non-responding to therapy, one because of treatment refusal. Twenty one from 25 children are alive from 5 to 51 months. Event frae survival of children with localized disease calculated according to Kaplan-Meier analysis was 64.17% in the 51st month. The main cause of failure in the treatment of osteosarcoma in children is primary and secondary progression of disease. The toleration and results of treatment for osteosarcoma in children according to the OS-SFOP-94 is satisfactory.

Adolescent↗
PubMed1998

[How to improve the results of treatment of myelodysplastic syndromes in the studies of Polish pediatric leukemia/lymphoma group].

Fourty two children with myelodysplastic syndrome (MDS) treated in seven centres of The Polish Paediatric Leukaemia/Lymphoma Study Group in period 1975-1998 were included in the study. In 16 children RAEB-T, in 3 CMML, in 10 RA and in 13 RAEB were diagnosed. BMT is the best therapy for children with MDS. For children, who have not a donor for BMT, Roacutan therapy seems to be the most effective.

Adolescent↗
PubMed1998

[Results of the treatment for infant acute lymphoblastic leukemia treated in the program Dana-Faber Cancer Institute. Report of Polish Pediatric Study Group for Leukemia and Lymphoma].

We present courses and treatment's results in 8 infants with acute lymphoblastic leukaemia (ALL) treated according Dana-Faber Cancer Institute protocol between 1994-1998 year. Complete remission (RC) was achieved in 8 children. Relapses were diagnosed between 6 to 20 month, only one achieved II RC. Four children are alive: in I RC-2, in II RC-1, in partial remission 1 and the treatment was ended in one. Treatment's results in infants with ALL are still unsatisfactory.

Antineoplastic Agents↗
PubMed1998

[The efficacy of G-CSF and GM-CSF in the adjunctive treatment of infections complicating chemotherapy of acute leukemia in children].

Growth factors (G-CSF Neupogen Roche i GM-CSF Leucomax Sandoz) have been applied in 133 therapeutic and prophylactic cycles in 88 children with acute leukaemias. GM-CSF and G-CSF were administered subcutaneously or intravenously at a dose of 2 to 8 micrograms/kg for 2 to 28 days. 45 prophylactic cycles had been administered in children with acute lymphoblastic leukaemia in high risk group and in relapses, which caused significant reduction in the number of infections, time of neutropenia and fever. Therapeutic cytokines cycles were applied when the absolute neutrophil count have fallen below 0.5 x 109/l. We observed significant reduction in duration of neutropenia in these cycles. Tolerance of GM-CSF and G-CSF was good. Side effects were not observed.

Adjuvants, Immunologic↗
PubMed1998

[The efficacy of G-CSF and GM-CSF in the adjunctive treatment of infections complicating chemotherapy of solid tumors in children. Report of Polish Pediatric Leukemia/Lymphoma Treatment Group].

Total number of 306 cycles of GM-CSF-Leucomax Sandoz (5 mg/kg/day s.c.) and/or G-CSF Filgrastim Hoffmann-La Roche (5-10 mg/kg/day s.c.) was applied in 146 children aged from 0.5-18 years during neutropenia associated with chemotherapy of solid tumours. Seventeen children with malignancies served as a historical control group. Our study have demonstrated after both G- and GM-CSF therapy shorter period of neutropenia, reduction of the number of febrile days and a decreased frequency of infectious complications and infection's duration.

Adjuvants, Immunologic↗