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Infants with alloimmune neonatal neutropenia (ANN) may be at risk of life-threatening infection. Various modalities of treatment have been attempted but with differing results. We describe a case treated with rHuG-CSF. The use of rHuG-CSF should be considered in children with ANN especially when associated with life-threatening infection.

The overall prognosis in children with medulloblastoma/PNET has not significantly improved over the past decade. Intensive neoadjuvant chemotherapy has not yet adequately explored. We evaluated the short-term clinical results of an intensive chemotherapy regimen in high risk children with newly diagnosed MB/PNET, after surgery and before radiation. Twelve previously untreated patients with high-risk medulloblastoma/PNET, according to Chang's classification, were treated with the following chemotherapy regimen: high dose carboplatin 600 mg/m2/day on days 1 and 2; the same course was administered 4 weeks later. One month later, high dose cyclophosphamide 2 g/m2/day on days 1 and 2, followed by an identical course 4 weeks later. Vincristine 1, 5 mg/m2 i.v. was given on the first day of each course. Systemic evaluation of the disease included imaging of the entire neuraxis, including MRI of the entire spine. Out of 12 enrolled, 7 patients were able to be evaluated for a residual disease after surgery. After two cycles of high dose carboplatin, we noted 1 CR, 4 PR and 2 MR. After the subsequent two cycles of high dose cyclophosphamide we observed an additional response in 4 cases. On the other hand, 4 patients clearly showed evidence of PD immediately after the first course of cyclophosphamide (2 cases) or following the second course. Three of the 4 patients had shown respectively 1 CR and 2 PR after the second course of carboplatin. Whereas it was confirmed that 2 courses of high dose carboplatin is effective in high risk MB/PNET children, we observed an unacceptable number of PD during the subsequent high dose cyclophosphamide therapy. A review from the literature also suggests that, in general, the longer radiotherapy is delayed, the higher the incidence of PD. In the search for the optimal drug combination in "sandwich chemotherapy" for children with high risk MB/PNET, PD must be reduced to an acceptable incidence, since a high number of PD may significantly lower the probability of long-term survival.

Detection of residual disease after completion of therapy or following bone marrow transplantation (BMT) in patients with acute promyelocytic leukaemia (APL) predicts relapse and is associated with a poor prognosis. Here we describe the successful treatment of residual disease post-transplant in APL using prolonged all-trans retinoic acid (ATRA) therapy in two children in whom autologous BMT (ABMT) had been performed in second complete remission (CR). ATRA treatment was well tolerated and found to be beneficial despite its prior use as a component of the initial induction protocol. ATRA therapy post-transplant led to molecular remission as determined by fluorescence in situ hybridization (FISH) as well as reverse transcriptase-polymerase chain reaction (RT-PCR) analyses and remission now exceeds 3.5 years in both patients. Overall, this study not only demonstrates that ATRA may successfully salvage APL patients with residual disease post-transplant, but also suggests a potential role for retinoids post-consolidation as a means of eliminating residual disease which could be beneficial even in patients previously exposed to ATRA as a component of the induction protocol.

Veno-occlusive disease of the liver (VOD) is an important complication in children with Wilms' tumour. Although in most patients this complication resolves uneventfully, fatal cases have been reported. Several observations strongly suggest that actinomycin-D is the likeliest cause of VOD in Wilms' tumour, but VOD seems to be rather uncommon in other malignancies treated with chemotherapy including actinomycin-D. The present case of VOD and the review of the literature stress the pathogenetic and clinical implications of VOD in the presence of a Wilms' tumour treated with actinomycin-D, originating in the right kidney. Greater awareness of this 'predisposing factor' may alert paediatricians to the presence of minimal signs of the syndrome.

Background: Standard chemo-radiotherapy methods for the treatment of children with advanced neuroblastoma (NBL) including bone marrow transplant approaches have been disappointing. These poor results can be ascribed to the evolution of residual drug-resistant cell populations. Curative attempts should therefore be directed to their elimination during induction treatment. This can best be accomplished through the use of multiple, non-cross-resistant agents early in therapy. 131I-Metaiodobenzylguanidine (131I-MIBG) provides a mechanism for the delivery of high doses of radiation to NBL lesions. Experience reported from several institutions indicates an approximate 50% response rate in previously treated children with advanced NBL., Conclusions: A better strategy is to employ 131I-MIBG together with intensive chemotherapy at the time of diagnosis. A pilot study adopting these principles and supported by laboratory data has been designed and is underway.

Objectives: To examine left ventricular function in patients previously treated with anthracycline for childhood malignancies. To evaluate the importance of age at the beginning of therapy, of total cumulative dose and of length of follow-up on late cardiac effects of anthracyclines., Design: Cross sectional echocardiography study of left ventricular function., Patients: Eighteen patients surviving between 1 and 9 years (median 2 years) from end of chemotherapy. Cumulative doses were between 120 and 550 mg/mq (median 275 mg/mq). Age at the beginning of chemotherapy was between 1.8 and 12.25 years (median 5.17 years). Nineteen healthy subjects were also studied as control group., Methods: Assessment of transmitral diastolic pulsed wave Doppler flow patterns and of transaortic pulsed wave Doppler flow patterns. Evaluation of systolic function measured by M-mode echocardiography., Results: Patients compared to controls showed a significative reduction of Ejection Fraction, of Shortening Fraction, of peak early phase to peak atrial phase filling velocity ratio and an increase of peak atrial phase filling velocity and of time-velocity integral of peak filling atrial phase. These alterations were more evident at doses higher than 250 mg/m2, in patients whose therapy started before 5 years of age and in patients whose follow-up was longer than 5 years., Conclusions: Significant abnormalities of systolic and diastolic function may appear some years after the end of anthracycline therapy for childhood malignancies. Therefore patient's continued follow-up is necessary in order to guide patient care and to better chemotherapeutic protocols.

Background: With the exception of a single study the cytogenetic aspects of leukemic cells in the central nervous system (CNS) have not been investigated., Patients and Results: During the course of a work-in-progress on the chromosomal constitution both of the spinal fluid and of bone marrow (BM) in children with acute myeloblastic leukemia (AML), we have observed a unique case of AML and CNS leukemia (CNSL) at diagnosis. The patient showed the simultaneous presence at diagnosis of a 46 cytogenetic line in the spinal fluid and a 47 (+8) cell line in the BM, present in the great majority of the metaphases examined., Discussion: This observation allows hypotheses on the relationship between BM and CNS disease in AML. Regardless of the pathogenetic mechanism, the cytogenetic findings of the present case clearly suggest that the leukemic population in the CNS compartment represents a less malignant cell process compared to the BM leukemic population. This easily fits in with the usually less malignant course of CNSL in AML., Conclusion: The foregoing findings may have critical pathogenetic and therapeutic implications.

Cranial irradiation (CI) is an effective way to prevent central nervous system (CNS) leukemia in children with acute leukemia (AL). However, it is still unclear whether the antileukemic effect of CI is mediated by alteration of blood-brain barrier (BBB) permeability and consequent increased levels of systemically administered drugs or whether it simply results from a direct cytolytic effect on leukemic cells in the meninges at diagnosis. We evaluated the influence of CI on BBB permeability to 1-beta-D-arabinofuranosylcytosine (ara-C) in 23 children with AL undergoing CI for CNS leukemia prophylaxis. CI was administered at 18 Gy (16 patients) and 24 Gy (7 patients). ara-C levels were measured in cerebrospinal fluid (CSF) and plasma before, during, and after CI. Two doses were evaluated: 75 mg/m2/day (12 patients) and 480 mg/m2/day (11 patients). CSF and plasma ara-C levels were measured when steady state was achieved. CSF:plasma ratios, obtained before, during, and after CI, were compared by an ANOVA model for repeated measures and by Tukey's test. At the 75-mg/m2/day dose, the mean values of ara-C CSF:plasma ratios before, during, and after CI were 0.20, 0.27, and 0.27, respectively. At the 480-mg/m2/day dose, the mean CSF:plasma ratios before, during, and after CI were 0.09, 0.12, and 0.13, respectively. No significant differences were observed when CSF:plasma ratios were compared before and during, during and after, and before and after CI. Our results indicate that CI at the doses used for CNS prophylaxis in AL does not significantly alter the BBB as far as ara-C is concerned.

Rhabdoid tumor of the kidney (RTK) is a quite rare malignant neoplasm of early childhood. It has a very unfavourable prognosis, since it tends to give early metastases and shows a poor response to chemotherapy regimens. We report a case of an infant with RTK, who had a rapidly progressive course. Based upon our case and the review of the literature, we would like to stress the importance of a differential diagnosis with another kidney cancer, namely Wilms tumor, which is more frequent and has by far a better prognosis.

We developed an animal model to evaluate the 125-I-metaiodobenzylguanidine (125-I-mIBG) biodistribution in tumor bearing mice. Six weeks old nude-atimic mice were subcutaneously injected with 30 x 10(6) cells of the human neuroblastoma (NB) cell line SH-SY5Y. TE-671, a rhabdomyosarcoma cell line, was used as a control tumor without a specific mIBG uptake mechanism. In order to prevent possible tumor rejection mediated by NK activity the anti asialo GM1 antiserum was administered intraperitoneally once a week for 4 weeks. The maximum anti asialo mediated effect was obtained by administering the first dose the same day as the cell implant. In this group of animals by 9 weeks 98% of mice had a measurable tumor. We have utilized this model to evaluate the biodistribution of 125-I-mIBG given as two different formulations: standard preparation with a specific activity of 84 mCi/mg and the no carrier added (n.c.a) formulation with a specific activity of approximately 8,000 mCi/mg. Our preliminary results indicate that the biodistribution of the two different formulations in the various organs are similar. Therefore it appears that n.c.a. mIBG should not cause an increased toxicity in possible normal target organs such as heart or adrenals. Additional experiments will be performed in this model to ascertain if there is a potential advantage of the clinical use of n.c.a. mIBG over the standard preparation.

Neuroblastoma (NB), a childhood radiosensitive tumor, is very aggressive and malignant, in its disseminated form, despite very intensive chemotherapy, prognosis continues to be dismal. Owing to its capacity to concentrate in NB lesions, large doses of 131-I-MIBG, have given very encouraging therapeutic results in patients resistant to conventional therapy as well as at diagnosis. We recently reported the first attempt in combination therapy (CO-TH) using 131-I-MIBG and cisplatin. This new form of CO-TH appears very effective in obtaining a rapid and excellent response in relapsed patients. In this report, we describe the results of further experience with CO-TH in disseminated NB. We have attempted to verify to what extent interaction between the effects of the two agents may produce therapeutic benefit, and we have sought the optimization of CO-TH use. Three stage IV NB patients were treated with CO-TH. The following treatment schedule, was planned: day 1, cisplatin 50 mg/m3 i.v. over 6 h; day 2, 131-I-MIBG 100-130 mCi at high specific activity (-1.1 Gbq/mg) i.v. over 6 h followed, a week later, by the same treatment combination. The therapeutic results were encouraging. However, hematological toxicity continued to represent a major limiting factor. In view of the overall effectiveness of CO-TH, at the price of lasting hematological toxicity, it may be indicated as a consolidation regimen some time before conditioning chemotherapy for autologous bone marrow transplantation.

In order to evaluate the influence of the coagulation instrument on the activated protein C (APC)-resistance plasma assay performed by a commercial kit, we tested 70 plasma samples on 4 different instruments during a simultaneous session run using a same lot of Coatest APC-resistance (Chromogenix). The results were analyzed employing three different modes of expression (aPTT prolongation in the presence of APC, APC-sensitivity ratio, normalized APC-sensitivity ratio) and three different diagnostic threshold values (below the control mean--2 standard deviations or the lowest control value or the 5th percentile of the control values). The inter-instruments variability in the mean values of the control individuals can be limited expressing the results as normalized-APC-sensitivity ratio (range 0.99-1.05). The overall diagnostic yield in thrombotic patients and their relatives depended mainly on the instrument employed and only in some cases on the mode of expression of the results and on the diagnostic threshold value. The sensitivity of the commercial assay on heterozygotes for factor V Leiden diagnosed by gene analysis was overall satisfactory (75-100%) but in some cases a lower diagnostic yield was noticed, depending on the type of instrument employed and/or the type of expression of the results and/or the diagnostic threshold values. Thus the instrument system adopted should be carefully considered in the interpretation of the results using the commercial kit.

Metastatic neuroblastoma (NB) continues to have a dismal prognosis. NB is a radiosensitive tumor. Owing to its high concentration in the NB lesions, Metaiodobenzylguanidine (MIBG) has the potential for specifically delivering very large radiation doses to the malignant cells. Encouraging results have been reported with [131I]MIBG used alone in patients resistant to conventional therapy and at diagnosis. We report the first attempts to explore the integration of this new treatment modality with chemotherapy. Among the drugs effective in NB, cisplatin was chosen because of its high degree of activity against NB, its mild hematologic toxicity and the known synergism between cisplatin and radiation. Four patients, 3 with relapsed, heavily pre-treated, progressive stage IV NB, and 1 with stage IV NB at diagnosis, all with a good [131I]MIBG uptake, were investigated with the combined therapy. Two complete remissions and one partial remission were observed in the relapsed patients 4-6 weeks following only one single course of both cisplatin and [131I]MIBG at the "standard" dosage. The only toxicity was hematologic, which was significant and relatively long-lasting, but was not associated with any serious infections or bleeding tendency. The general condition of these patients during the entire study period was excellent. The 4th patient, investigated at diagnosis with a modified less intensive treatment, obtained a partial remission with a mild hematologic toxicity. The provisional conclusion of this preliminary study is that this new form of combined therapy appears very effective in heavily pretreated relapsed patients with progressive disease, and could also be investigated in refractory patients and in patients at diagnosis.

The mechanisms underlying acute promyelocytic leukemia (APL) coagulopathy and its reversal by administration of all-trans retinoic acid (ATRA) have been investigated. Bone marrow promyelocytic blasts from nine patients with APL were cultured with or without ATRA 1 mumol/L. Cultured blasts (days 0, 3, 6, and 9) were washed, resuspended in phosphate buffer, lysed by freezing and thawing, and then assayed for procoagulant activity (PCA), elastase activity, tissue factor (TF) antigen, tissue-type plasminogen activator (t-PA) antigen and urokinase-type plasminogen activator (u-PA) antigen. PCA was determined by a recalcification assay. Elastase was measured by an amidolytic assay (S-2484). TF, t-PA, and u-PA antigens were measured by an enzyme-linked immunosorbent assay (ELISA). Malignant promyelocytes isolated from the patients had increased levels of PCA and TF as compared with the control polymorphonucleates, and low levels of elastase, t-PA, and u-PA; the patient blast PCA level was significantly related to the degree of hypofibrinogenemia. In this system, blast PCA depended on the tissue factor and was significantly correlated to the TF antigen values. In the cultures without ATRA, PCA, TF, and u-PA progressively increased, whereas elastase and t-PA levels remained essentially unchanged. In the presence of ATRA, all parameters (except u-PA) decreased during the culture time. Thus, a major role of the promyelocytic blast cell PCA in the pathogenesis of M3-related coagulopathy is suggested; the ATRA effect on coagulopathy seems mainly mediated by a downregulation of the PCA.

A diagnosis of myelodysplastic syndrome was made in an 18-year-old patient with Warkany syndrome due to constitutional trisomy 8 mosaicism. The possible causal role of this particular chromosome constitution with respect to myelodysplasia and embryonal childhood tumors is discussed.

Few studies have been carried out regarding preoperative chemotherapy utilized in the treatment of primitive neuroectodermal tumors/medulloblastomas (PNET/MB). In this paper, the authors report 3 cases of children under three years of age, with a presumed diagnosis of PNET/MB, who were preoperatively treated with chemotherapy consisting of high doses of carboplatin alone. The treatment improved the childrens' clinical condition prior to surgery and facilitated tumor removal, resulting in partial regression of the tumor. The preoperative single-drug therapy did not affect the histological diagnosis or prevent the presence of an effective degree of tumor sensitivity to the drug. All three children are still disease-free, after a mean follow-up period of 42 months.

Sixteen patients with high risk MB/PNET at diagnosis were included in a pilot study employing carboplatin (CBDCA) as a single drug prior to conventional therapy. The main goal of the study was to identify in a short-term trial a significant response that would predict further response to CBDCA in the single patient. Exploration of CBDCA activity was focused on response after the first course as compared to the response following the second course. A course consisted of CBDCA 600 mg/m2 on days 1 and 2 administered in a 1 h infusion to be repeated 3-4 weeks later. After two cycles we observed 1 CR and 9 PR, that is a 62% response rate. The first course resulted in 5 PR, 5 MR, 5 SD, and 1 PD; after the subsequent course in all responding patients, response persisted or improved whereas in no patient with SD any improvement was observed. The correlation of response to the first course with response to the second course was statistically significant (P = 0.0009). The main toxicity of the single course was hematologic and consisted of rapidly reversible grade 3-4 neutropenia and thrombocytopenia in 94% of patients. Pharmacokinetic studies showed a very limited interpatient variability of both Cmax 57.6 +/- 9.9 micrograms/ml) and AUC (15.3 +/- 1.5 mg/ml.min) of free CBDCA, which eliminates an important variable in the evaluation of response. In conclusion, this "in vivo test" appears effective, reasonably safe, and reproducible in identifying patients likely to benefit from CBCDA: after a period of time as short as 3-4 weeks following the first course, multidrug chemotherapy including CBDCA may be employed in the responding patients, whereas an alternative regimen would be indicated in the non-responding patients.

[131I]metaiodobenzylguanidine ([131I]MIBG) is selectively taken up and stored by tumours derived from the neural crest, and is used for diagnosis and treatment of neuroblastoma (NB). The antitumoral effect of [131I]MIBG is closely related to the intracellular level of the radiopharmaceutical compound, which is dependent on uptake and storage/release mechanisms. While MIBG uptake is well characterised, storage and release mechanisms are still controversial. In order to better characterise [125I]MIBG release mechanisms, we studied the basal and stimulated efflux of [125I]MIBG in the human NB cell line, SH-SY5Y, preloaded with 0.1 microM [125I]MIBG for 1 h. We found that [125I]MIBG basal efflux is highly temperature-dependent, that [125I]MIBG release, induced by cell depolarisation with high potassium, is mainly calcium-independent, and induced by exchange with cold MIBG or noradrenaline, inversion of the sodium gradient across the cell membrane by veratridine by substitution of sodium chloride with equimolar concentration of lithium chloride. The exposure of NB cells to imipramine, an Uptake-1 inhibitor, also produces a net stimulatory effect on [125I]MIBG release. However, when used in association with other releasing stimuli, such as higher levels of intracellular sodium or external agonists, imipramine abolishes the consequent increase of [125I]MIBG release. Our findings suggest that stimulated [125I]MIBG release is mediated by a carrier, most probably the uptake carrier working in a reverse mode, while a minimal fraction of [125I]MIBG is released by an exocytotic mechanism.

Taxanes are an important new class of anticancer agents that inhibit cell division by the unique mechanism of increasing the rate of microtubule assembly and preventing microtubule depolymerisation. Using the colony inhibition assay, we compared the cytotoxicity of paclitaxel and docetaxel in three human neuroblastoma (NB) cell lines, SH-SY5Y, BE(2)M17 and CHP100. Different exposure times (3, 6, 12, 24, 48 and 72 h) and different concentrations ranging from 0.1 nM to 10 microM were tested. Both paclitaxel and docetaxel show antineoplastic activity in human NB cell lines. Taxanes' antitumour activity varied among the different cell lines, CHP100 being the most sensitive and SH-SY5Y the least sensitive. Paclitaxel cytotoxicity appears schedule-dependent, with marked cell kill observed only for exposures of 24 h or longer. Docetaxel cytotoxicity was dependent upon prolonged exposure only in the SH-SY5Y cell line, while an exposure time of 3-6 h resulted in exponential cell kill in the other two cell lines. Docetaxel was more cytotoxic than paclitaxel with a mean ratio of (paclitaxel/docetaxel) IC50 values ranging from 2 to 11. For both taxanes, we observed good correlation between cytotoxic effect and percentage of cells blocked in G2/M phase. A cytotoxic effect occurred at concentrations comparable with those achieved in the plasma of patients treated with these agents in initial clinical trials. The full potential of prolonged infusion or repeated daily administrations of taxanes should be explored in clinical studies, and responses to taxanes in neuroblastoma should be assessed in paediatric phase II studies.

Microheterogeneity of antithrombin III (AT-III) was investigated by crossed immunoelectrofocusing (CIEF) on eleven molecular variants. A normal pattern was found in five variants while two different abnormal CIEF patterns were found in the other four and two variants, respectively. Point mutations causing a major pI change (exceeding 4.0) of the amino acid substituted lead to alterations in the overall microheterogeneity. The variants thus substituted share a first type of abnormal CIEF pattern with alterations throughout the pH range, regardless of the location of the mutation (reactive site and adjacent regions or heparin binding region). Minor amino acid pI changes in these regions do not alter the AT-III overall microheterogeneity, whatever the resulting functional defect. However, if the mutation is placed in the region around positions 404 or 429, then even minor changes of the amino acid pI seem able to alter the overall charge, leading to a second type of abnormal CIEF pattern with the main alteration at pH 4.8-4.6. Neuraminidase treatment leads to disappearance of microheterogeneity except for the variants with the Arg393 to Cys substitution. Addition of thrombin induces CIEF modifications specifically related to the functional defect. A normal formation of thrombin-antithrombin complexes induces a shift towards the more acid pH range, whereas in the variants substituted at the reactive site the CIEF pattern is substantially unaffected by thrombin; variants substituted at positions 382-384 show a maximal thrombin-induced increase of the isoforms at pI 4.8-4.6. Therefore mutant antithrombins with different functional abnormalities but sharing a common CIEF pattern were well distinguished.(ABSTRACT TRUNCATED AT 250 WORDS)