Differential ex vivo activity of bortezomib in newly diagnosed paediatric acute lymphoblastic and myeloblastic leukaemia.

The proteasome inhibitor, bortezomib, is known to be effective in the therapy of various neoplasms. The objective of this study was the analysis of the ex vivo activity of bortezomib in paediatric acute lymphoblastic leukaemia (ALL), in comparison to paediatric acute myeloid leukaemia (AML). A total of 159 patients entered the study, including 106 ALL (including 86 precursor-B-cell ALL, and 20 T-cell ALL) and 53 AML children. The ex vivo sensitivity to bortezomib and 16 other drugs was studied by MTT assay. Paediatric AML samples were more resistant than paediatric ALL samples to most of the tested drugs, except for cytarabine and thioguanine. With respect to immunophenotype, ex vivo drug resistance in T-cell ALL (T-ALL) was higher for most of the drugs. No differences in drug resistance between T-ALL and common/pre-B-cell-ALL were found for daunorubicin, mitoxantrone and 6-thioguanine. Bortezomib was the only compound which was more active in T-ALL than in common/pre-B-ALL paediatric samples. In conclusion, bortezomib had good ex vivo activity in paediatric T-ALL samples.

Prognostic impact of combined fludarabine, treosulfan and mitoxantrone resistance profile in childhood acute myeloid leukemia.

BACKGROUND: The role of cellular drug resistance in childhood acute myeloid leukemia (AML) has not yet been established. The aim of the study was the analysis of the clinical value of ex vivo drug resistance in pediatric AML. PATIENTS AND METHODS: A cohort of 90 children with de novo AML were assayed for drug resistance profile by the 3-4,5-dimethylthiazol-2-yl-2,5-difenyl tetrazolium bromide (MTT) assay and prognostic model of in vitro drug sensitivity was analyzed. RESULTS: Children who relapsed during follow-up showed higher in vitro resistance of leukemic blasts to most of the drugs tested, except for cytarabine, cladribine, vincristine, mercaptopurine and thioguanine. A combined in vitro drug resistance profile to fludarabine, treosulfan and mitoxantrone (FTM score) was defined and it had an independent prognostic significance for disease free survival in pediatric AML. CONCLUSION: The combined fludarabine, treosulfan and mitoxantrone resistance profile to possibly may be used for better stratification of children with AML or indicate the necessity for additional therapy.

[Acute pancreatitis during chemotherapy of acute lymphoblastic leukaemia complicated with pseudocyst]. / Ostre zapalenie trzustki powiklane pseudotorbiela w trakcie chemioterapii ostrej bialaczki limfoblastycznej.

The incidence of pancreatitis in patients with haematopoetic neoplasms who are treated with L-asparaginase is fom 2 to 24%. In majority of cases the pancreatitis is oedematous and self-limiting. Acute haemorrhagic or necrotizing pancreatitis caused by L-asparaginase is rare but potentially life-threatening complication. We present 2 cases of acute pancreatitis in children aged 2 and 4 years. They were diagnosed to have acute lymphoblastic leukaemia and were treated according to the ALLLIC BFM 2002 protocol. Acute pancreatitis developed in these children after induction therapy and was followed by formation of a pseudocyst. In both cases the diagnosis of this complication was made directly after phase I of the protocol I (after eighth dose of L-Asparaginase). In the first case the course of acute pancreatitis was mild. Normalization of the amylase levels occurred after 7 days and the diagnosis of post inflammatory cyst was made 15 days after the first signs of the disease. But thereafter, during the additional complication (pneumonia with Pseudomonas aeruginosa bacteriemia) the pancreatic cyst became infected. In the second case acute pancreatitis had a severe course and the child required treatment in the Intensive Care Unit for 21 days. The cyst was diagnosed after 20 days from the beginning of symptoms. The surgical procedure, applied in both cases was internal drainage by anastomosis of the cyst with the back wall of the stomach. Antileukaemic treatment was recommenced after 6-8 weeks when complications resolved. Currently both children are well and remain in haematological remission and continue maintenance chemotherapy.

[Lymphoproliferative disorder as a complication after haematopoietic stem cell transplantation]. / Choroba limfoproliferacyjna jako powiklanie po przeszczepieniu komórek macierzystych szpiku.

Lymphoproliferative disorders (LPD) occur often in EBV-infected patients, especially in solid-organ and haematopoietic stem cell transplant recipients. The risk of developing LPD ranges from 1 to 25% and depends on the type of transplantation. We are presenting the case of a 9-year-old boy with acute myelogenous leukaemia in second remission, who developed LPD after matched unrelated donor bone marrow transplantation (MUD BMT) not identical in two loci. On day 50 after BMT the patient presented with fever and symptoms of paronychia. Two weeks later, bilateral cervical tenderness and adenopathy and hepatosplenomegaly developed. Bone marrow biopsy confirmed continuing remission. An extensive infection workup, including bacterial, mycotic and CMV infection yielded negative results. Basing on clinical picture and suspecting LPD, EBV-PCR was performed. The patient was found to have extremely high EBV DNA levels (4.905.152 genomes/mcg) in the peripheral blood. On days 64 and 73 after BMT, the patient received two doses of rituximab (MabThera) (375 mg/m(2)) After the first dose of rituximab EBV DNA copy numbers decreased to 707.723/mcg. However the patient's general condition was worsening; 71 days after BMT increasing aplasia and symptoms of venoocclusive disease (VOD) developed. The patient received two doses of defibrotide (Novarid). Despite of intensive therapy, progressive hepatic failure and increasing pulmonary oedema led to the patient's death, on day 96 after BMT.

Predictive value of multidrug resistance proteins and cellular drug resistance in childhood relapsed acute lymphoblastic leukemia.

PURPOSE: Cellular resistance in childhood acute leukemias might be related to profile and function of multidrug resistance proteins and apoptosis regulating proteins. The aims of the study were: (1) analysis of expression of MRP1, PGP1, LRP, BCL-2 and p53 proteins; (2) correlation with ex vivo drug resistance, and (3) analysis of their prognostic impact on clinical outcome in childhood acute lymphoblastic (ALL) and acute myeloid (AML) leukemia. METHODS: Total number of 787 children diagnosed for initial ALL (n = 527), relapsed ALL (n = 104), initial AML (n = 133) and relapsed AML (n = 23) were included into the study. Mean follow-up period was 3.5 years. Drug resistance for up to 30 anticancer agents was performed by the MTT assay. Expression of all proteins was tested by flow cytometry. RESULTS: Both initial AML and relapsed ALL samples showed higher drug resistance than initial ALL samples. No significant differences were found in drug resistance between initial and relapsed AML samples. The presence of multidrug resistance and apoptosis proteins had no impact on pDFS in iALL and iAML, however strong trend towards adverse prognostic impact of MRP1, PGP and LRP on pDFS in rALL was observed. The same trend was observed for each of analyzed co-expressions of tested multidrug resistance proteins. CONCLUSIONS: The phenomenon of cellular drug resistance in childhood acute leukemias is multifactorial and plays an important role in response to therapy. Expression of MRP1, PGP and LRP proteins, as well as their co-expression play possible role in childhood relapsed ALL.

[The health state evaluation in persons after therapy of Hodgkin's disease in childhood: report of the Polish Pediatric Leukemia/Lymphoma Study Group]. / Ocena stanu zdrowia osób z zakonczonym w dziecinstwie leczeniem choroby Hodgkina: raport Polskiej Pediatrycznej Grupy ds. Leczenia Bialaczek i Chloniaków.

The introduction of modern methods of combined therapy: chemotherapy and radiotherapy, allows the cure more than 90% of children and adolescents with Hodgkin's disease. However, the intensive treatment may cause early and late complications. The late complications may include: damage of soft tissues and respiratory, cardiovascular, skeletal, and endocrine systems, and second cancers. Late complications may impair the patients' quality of life after cessation of therapy. This study presents evaluation of health status of persons who underwent therapy for pediatric Hodgkin's disease in centers of Polish Pediatric Leukemia/Lymphoma Study Group. The special questionnaire was established to collect data concerning hematopoietic system function, damage of soft tissues and skeletal system, thyroid and reproductive organs function, respiratory, cardiovascular, and nervous system function, liver and kidney function, status of dentition, occurrence of infections, immunologic system function, and psychological and social problems. The project included patients treated in 9 pediatric oncology centers. During the study the questionnaires of 288 patients [151 boys (52.4%) and 137 girls (47.6%)] in whom treatment of Hodgkins's disease started in 1994-1996 (44 questionnaires), and in 1997-2001 (244 questionnaires). In 42 patients no diagnostic procedures were performed. In this group 20 patients are currently under care of adult oncology clinics, 21 failed to come for a visit, and one patient is treated because of HD progression. The questionnaires of 246 patients treated in 1994-1996 (25 questionnaires) and 1997-2001 (221 questionnaires), were analyzed and the data on the late complications of these patients were obtained. General health status of examined patients was found satisfactory. However, 2.3% of patients had radiological evidence of pulmonary fibrosis, and 4.9% had various ECG abnormalities. Endocrine therapy is needed in 4.5% of patients because of thyroid function abnormalities. Second cancers were diagnosed in 1.7% of patients. The health status of children and adolescents cured from Hodgkin's disease and other childhood cancers should be regularly evaluated. Results of these evaluations will be the basis for introducing new treatment protocols aimed of decreasing the incidence of late complications while maintaining or improving cure rates.

[Progress in the treatment of non-Hodgkin's lymphoma (NHL) in children. The report of Polish Pediatric Leukaemia/lymphoma Study Group (PPLLSG)]. / Postep w leczeniu nieziarniczych chloniaków zlosliwych (NHL) u dzieci. Raport Polskiej Pediatrycznej Grupy ds. Leczenia Bialaczek i Chloniaków u Dzieci (PPGLBC).

Treatment results of non-Hodgkin lymphoma (NHL) in children has been shown in this study. From 1979 to 2003 children were registered with the diagnosis of NHL in oncology centers of Polish Pediatric Leukaemia/Lymphoma Study Group, a group of 397 patients with NHL B, 222 pts with NHL T and 54 pts with anaplastic large cell lymphoma (ALCL). The pts with NHL T have been treated according to BFM-90 protocol. The predominant primary site of disease was mediastinum (59.3%). Complete remission (CR) was achieved by 87%. EFS for all NHL T pts was 65% and 56% for pts with extensive tumours and 73% for pts with tumours < 10 cm. Patients with NHL B were treated according to the adopted LMB-89 protocol. The majority were Burkitts type and presented abdominal location (50%). 80% with disseminated disease. CR was achieved by 89% patients, but 94% with LDH < 500 IU/L and 73% with LDH > 500 IU. The median time of follow up was 53 months. EFS was 73% for all patients. The patients with ALCL were treated according to several protocols. Peripheral nodes were the most often primary location (40%), than mediastinum (24%) and abdomen (21%). EFS for all pts was 63%. Despite great progress in the therapy of NHL in children during 20 years of observation, the results are not satisfactory in disseminated stages. It is necessary to look for new prognostic markers which make it possible to improve classification of patients. Major surgery in advanced stages is not recommended since it delays chemotherapy and fails to improve overall survival. Early detection of neoplasm is one of the most important efforts to improve therapy success.

In vitro activity of glufosfamide in childhood acute leukemia.

Glufosfamide is a new agent for cancer chemotherapy. The objective of the study was the comparison of the in vitro drug resistance profile of glufosfamide with other oxazaphosphorines in 106 samples of childhood acute leukemia by means of the MTT assay. The following drugs were tested: glufosfamide, 4-HOO-ifosfamide, 4-HOO-cyclophosphamide, mafosfamide cyclohexylamine salt, prednisolone, vincristine, L-asparaginase, daunorubicin and cytarabine. In the group of initial Acute Lymphoblastic Leukemia (ALL) samples, equivalent cytotoxicity values for glufosfamide, 4-HOO-ifosfamide, 4-HOO-cyclophosphamide and mafosfamide were 5.95, 9.92, 4.60 and 3.90 microg/ml, respectively. In comparison to initial ALL samples, the relative resistance for glufosfamide and 4-HOO-ifosfamide in relapsed ALL samples were 1.9 (p=0.049) and 1.3 (ns), and in initial Acute Myeloblastic Leukemia (AML) samples, respectively, 31 (p<0.001) and 5 (p=0.001). All oxazaphosphorines showed highly significant cross-resistance. In conclusion, in vitro activity of glufosfamide is comparable to ifosfamide. Glufosfamide shows high activity against lymphoblasts both on diagnosis and on relapse, however it cannot circumvent resistance to other oxazaphosphorines.

Ex vivo drug resistance profile in childhood acute myelogenous leukemia: no drug is more effective in comparison to acute lymphoblastic leukemia.

Therapy results in childhood acute myelogenous leukemia (AML) differ from those of acute lymphoblastic leukemia (ALL). Cellular drug resistance might be one of the reasons of therapy failure in AML. The aim of the study was the analysis of ex vivo drug resistance profile in childhood initial and relapsed AML in comparison to initial ALL. Fifty-three AML samples were tested for chemosensitivity and results were compared with those of 106 initial ALL samples. Ex vivo drug resistance was tested by means of the MTT assay. Up to 29 cytotoxic drugs were tested for each patient. When compared to de nova ALL samples, myeloblasts from initial AML samples were significantly more resistant to most tested drugs, except cytarabine, mercaptopurine and thioguanine. Relapsed AML samples, in relation to initial AML samples, showed comparable sensitivity to cytarabine, idarubicin, fludarabine and cladribine. Patients, who have died due to refractory or relapsing disease, were already on first diagnosis 2-fold more resistant to cytarabine, 6.4-fold more resistant to cisplatin and 3-fold more resistant to carboplatin, when compared to those who stay in remission. Resistance to prednisolone was observed in 85% initial and all relapsed AML samples, in comparison to 33% of ALL samples. Resistance to cytarabine occurred in 2.1% of ALL and 12% of AML cases while a patient with Down syndrome presented the most sensitive drug resistance profile. In conclusion this study shows that no drug was found which, on average, was more effective in AML than in ALL samples. The sensitivity of myeloblasts to platinum derivatives might have prognostic value.