Summary To determine the epidemiology and outcome of children with Down syndrome (DS) diagnosed with acute leukaemia in the Nordic countries, data registered in the Nordic Society of Paediatric Haematology and Oncology (NOPHO) population‐based leukaemia registry were analysed. Of 3494 children with acute leukaemia diagnosed between July 1984 and December 2001, 136 patients (3·9%) with DS were identified. 2·1% of the children with acute lymphoid leukaemia (ALL) and 14·0% of the children with acute myeloid leukaemia (AML) had DS. In ALL, DS patients had similar age and sex distribution and no major differences in blood counts compared with non‐DS children. None of the DS patients had T cell leukaemia. Outcome was inferior to that of non‐DS children and treatment results did not improve over time. In AML, DS patients showed a significant female predominance and all but one were <5 years old. DS patients with AML had significantly lower platelet and white blood cell counts and two‐thirds were type M7 as according to the French–American–British classification. None of the patients <5 years of age had typical AML cytogenetic aberrations. Outcome was far better in the DS group. DS patients treated for AML after 1992 had an excellent outcome (probability of event‐free survival, 83 ± 6%). The high proportion of female DS patients with AML is unexplained. The differing treatment results in AML versus ALL need further evaluation and represent a challenge for the coming years.

In all, 447 children with acute myeloid leukaemia (AML) have been treated on three consecutive NOPHO studies from July 1984 to December 2001. NOPHO-AML 84 was of moderate intensity with an induction of three courses of cytarabine, 6-thioguanine and doxorubicin followed by four consolidation courses with high-dose cytarabine. The 5-year event-free survival (EFS), disease free survival (DFS) and overall survival (OS) were 29, 37 and 38%. NOPHO-AML 88 was of high intensity with the addition of etoposide and mitoxantrone in selected courses during induction and consolidation. The interval between the induction courses should be as short as possible, that is, time intensity was introduced. The 5-year EFS, DFS and OS were 41, 48 and 46%. In NOPHO-AML 93, the treatment was stratified according to response to first induction course. The protocol utilised the same induction blocks as NOPHO-AML 88, but after the first block, children with a hypoplastic, nonleukaemic bone marrow were allowed to recover before the second block. Consolidation was identical with NOPHO-AML 88. The 5-year EFS, DFS and OS in NOPHO-AML 93 were 48, 52 and 65%. The new NOPHO-AML protocol has been based on experiences from previous protocols with stratification of patients with regard to in vivo response and specific cytogenetic aberrations.

From July 1984 the five Nordic countries (Denmark, Finland, Iceland, Norway and Sweden) have registered all children with acute myeloid leukaemia (AML) and treated them on two consecutive protocols of different intensity (NOPHO-84 and NOPHO-88). We probably have information on every child with this diagnosis in our region. We found an annual incidence of AML of 0.7 new cases per 100,000 children < 16 years of age. We observed a distinct peak of incidence in the first 2 years of life. Children with Down's syndrome accounted for 13% of all cases. Eighty of 105 cases treated on NOPHO-84 achieved remission (78%). In NOPHO-88, 100/118 patients entered remission (85%). The overall event-free survival (p-EFS) for the two studies was 0.32 for NOPHO-84 and 0.42 for NOPHO-88. The majority of relapses occurred within 2 years of diagnosis. When looking for prognostic factors the strongest significant adverse factor found was male sex. Children with Down's syndrome (n = 35) had a very favourable outcome if they received therapy according to protocol, and infants (n = 26) had a superior outcome compared to children 1-2 years or > 10 years of age at diagnosis.

Death signaling by Fas and TNF receptors plays a major role in the control of activated mature T cells. However, the nature of the death receptors, which may be used by the immune system to control T cells that have not acquired susceptibility to Fas ligand or TNF, is not established. In this study, we demonstrate that engagement of distinct epitopes on CD99 rapidly induces T cell death by a novel caspase-independent pathway. A new mAb to these CD99 epitopes, Ad20, induces programmed cell death of transformed T cells as determined by morphological changes, phosphatidylserine exposure on the cell surface, and uptake of propidium iodide. In general, ligation of CD99 induced kinetically faster and more profound death responses as compared with the impact of anti-Fas and TNF-related apoptosis-inducing ligand (TRAIL). Ad20-induced programmed cell death was observed with seven of eight T cell lines examined, and notably, only two of these were distinctly responsive to anti-Fas and TRAIL. CD99-mediated death signaling proceeded independently of functional CD3, CD4, CD45, and p56lck, revealed distinctions from CD47-mediated T cell death responses, and was not influenced by interference with CD47 signaling. In contrast to the effect on transformed T cell lines, Ad20-induced death responses were not observed with normal peripheral T cells. Thus, our data suggest that CD99 is linked to a novel death pathway that may have biologic relevance in control of early T cells.

Summary. Three consecutive protocols for childhood acute myeloid leukaemia (AML) have been used in the Nordic countries since 1984: the Nordic Society for Paediatric Haematology and Oncology (NOPHO)-AML84 was of moderate intensity, NOPHO-AML88 of high intensity with upfront loading and aggressive consolidation. NOPHO-AML93 utilized the same treatment blocks as NOPHO-AML88, but after the first block those children with a hypoplastic non-leukaemic bone marrow were allowed to recover from aplasia. Poor responders received intensified induction therapy. Between January 1993 and December 2000, 219 children without Down's syndrome were entered on NOPHO-AML93. Compared with NOPHO-AML88, the event-free survival (EFS) at 7 years increased from 41% to 49% (P ¼ 0AE06) and 7-year overall survival increased from 47% to 64% (P < 0AE01). Toxic death during induction was reduced from 10% to 3%. Survival was similar in patients receiving stem cell transplantation or chemotherapy only in first remission. The major prognostic factors in NOPHO-AML93 were response to therapy and cytogenetics. A total of 67% of patients achieved remission after the first induction course and showed an EFS of 56% compared with 35% in those not in remission (P < 0AE01). Cytogenetic results were obtained in 95% of patients. Patients with t(9;11) (p22;q23) (n ¼ 16) experienced a significantly better EFS (86%) than other cytogenetic groups. The overall outcome was improved by employing the previous toxic protocol with different timings, and through individualizing therapy according to the initial response of the patient.

No abstract

26-Hydroxylation of 5j6-cholestane-3a,7a,12a-triol and other C2rsteroids was demonstrated in cultured skin fibroblasts from healthy individuals. Activities in skin fibroblasts were -5-10% of those previously found in human liver homogenates, and were inhibited by CO. The apparent K., was lowest for 5,B-cholestane3a,7a,12a-triol (1.3 Mmol/liter) and highest for 5-cholestene-3(3,7a-diol (12 Mmol/liter). The rate of 26-hydroxylation was highest with 7a-hydroxy4-cholesten-3-one. These characteristics are similar to those of hepatic mitochondrial C2rsteroid 26-hydroxylase.In skin fibroblasts from three patients with cerebrotendinous xanthomatosis (CTrX), 26-hydroxylation of C2rsteroids proceeded at a rate of only 0.2-2.5% of healthy controls. No accumulation of endogenous 5,B-cholestane-3a,7a,12a-triol could be demonstrated in these cells, and the lowered formation of radioactive, 26-hydroxylated products could not be explained by dilution of the labeled exogenous substrate.The present results add strong evidence to the concept that the primary metabolic defect in CTX is a deficiency of Cr-steroid 26-hydroxylase.

Tumor samples from 58 patients diagnosed and treated for neuroblastoma or ganglioneuroblastoma in a single institution from 1967 to 1981 were included in a study of prognostic factors. Histopathology, certain immunohistochemical markers, and DNA ploidy were evaluated along with clinical variables such as tumor stage, primary site, and patient's age at diagnosis. Children under 1.5 years of age at diagnosis had a much better prognosis than did older ones, and this variable was the best prognostic indicator. Tumor Stages I to II and IVS, primary tumor site above the diaphragm, and tumor differentiation were also related to a better prognosis. The Shimada classification was of no additional prognostic value in our study. Neither was the immunohistochemical marker pattern, but it was sometimes helpful in establishing the tumor diagnosis. Tumor-cell ploidy, however, seemed to afford additional prognostic information because the 11 patients with aneuploid tumors under the age of 1.5 years at diagnosis all survived in contrast to only five of nine patients with diploid tumors in the same age group. It is possible that this was due to a better response to treatment in the aneuploid group. Our results suggest that patients with diploid neuroblastomas of undifferentiated histology and those over the age of 1.5 years at diagnosis might be selected for more intense treatment.