Childhood myelodysplastic syndrome in Denmark: incidence and predisposing conditions.

Myelodysplastic syndrome (MDS) in childhood is considered to be very rare, but sound epidemiologic data are lacking. We report a population-based study of MDS in Denmark from 1980 to 1991. The medical charts were reviewed of 988 children identified from the Danish National Hospital Discharge Registry with a diagnosis of myeloid leukemia or blood cytopenia. Blood and bone marrow smears from all cases of possible MDS were re-evaluated. The cases were categorized according to the FAB classification, with the exception of chronic myelomonocytic leukemia (CMML) in which more than 5% myeloblasts in the blood was accepted. Juvenile chronic myeloid leukemia (JCML) was included as CMML. MDS was diagnosed in 46 children representing 9% of all hematologic malignancies in children less than 15 years of age. The annual incidence was 4.0/million and did not increase with time. Refractory anemia with excess of blasts and CMML each accounted for one third of the cases. Down syndrome was present in seven children. Other predisposing conditions included Fanconi anemia, neurofibromatosis, constitutional trisomy 8 mosaicism, and familial leukemia. Only one child had therapy-related MDS. The study indicates that the incidence of childhood MDS is higher than generally assumed and approximate to the incidence of acute myeloid leukemia.

Transient pancytopenia preceding acute lymphoblastic leukemia (pre-ALL).

Pancytopenia followed by a period of spontaneous recovery may precede the diagnosis of acute lymphoblastic leukemia (pre-ALL). Although both pre-ALL and myelodysplastic syndromes are preleukemic in a strictly temporal sense, there are several marked differences between the two conditions. We present eight children with pre-ALL who represented 2% of all cases of childhood ALL. The bone marrow was normo- or hypocellular with increased reticulin fibrosis during the pre-ALL phase. No cytogenetic abnormalities were found at the pre-ALL phase, but had developed at the time of overt leukemia in four of the six children examined. Based on the findings in our patients and on cases reported in the literature, we argue that pre-ALL is likely to represent a paraneoplastic syndrome early in the leukemic development that might be mediated via inhibitory properties related to clonally expanding but still cytogenetically normal cells. The findings may indicate a multistep pathogenesis of ALL.

Intensive chemotherapy in childhood myelodysplastic syndrome. A comparison with results in acute myeloid leukemia.

Myelodysplastic syndrome (MDS) in children is often considered as a variant of acute myeloid leukemia (AML) and frequently treated as such. However, there are very few reported data on the outcome following AML treatment. We analyzed 20 consecutive cases of de novo MDS treated in Denmark according to the NOPHO AML protocols. The results were compared with those obtained in 31 children with de novo AML treated with the same protocols, and with the outcome in 10 children with MDS who received allogeneic bone marrow transplantation (BMT) without prior AML therapy. Distinction between MDS and AML was made morphologically according to the FAB criteria. All children were followed for at least 37 months. The proportion of complete remission in MDS and AML was 35 percent vs 74 percent. (P = 0.005), resistant disease 25 percent vs 10 percent (P = 0.14), death in cytopenia 40 percent vs 16 percent (P= 0.06), and 3-year survival 15 percent vs 35 percent. (P = 0.11), respectively. Duration of treatment-related cytopenia was similar in MDS and AML, except for a longer period of leukopenia in MDS following the second course of induction. Seven of 10 MDS children receiving BMT without prior chemotherapy are long-term survivors. Our data suggest that conventional AML regimens are associated with a low rate of complete remission, a high risk of death in cytopenia, and a limited curative potential in childhood MDS. Allogeneic BMT was in contrast associated with a high survival rate. BMT may, at least in some patients, be performed successfully without prior induction chemotherapy. The different response to therapy in MDS and AML may reflect fundamental biological differences between the two conditions.

A pediatric approach to the WHO classification of myelodysplastic and myeloproliferative diseases.

Myelodysplastic and myeloproliferative disorders are rare in childhood and there is no widely accepted system for their diagnosis and classification. We propose minimal diagnostic criteria and a simple classification scheme which, while based on accepted morphological features and conforming with the recent suggestions of the WHO, allows for the special problems of myelodysplastic diseases in children. The classification recognizes three major diagnostic groups: (1) juvenile myelomonocytic leukemia (JMML), previously named chronic myelomonocytic leukemia (CMML) or juvenile chronic myeloid leukemia (JCML); (2) myeloid leukemia of Down syndrome, a disease with distinct clinical and biological features, encompassing both MDS and AML occurring in Down syndrome; and (3) MDS occurring both de novo and as a complication of previous therapy or pre-existing bone marrow disorder (secondary MDS). The main subtypes of MDS are refractory cytopenia (RC) and refractory anemia with excess of blasts (RAEB). It is suggested retaining the subtype of RAEB-T with 20-30% blasts in the marrow until more data are available. Cytogenetics and serial assessments of the patients are essential adjuncts to morphology both in diagnosis and classification.

The International Prognostic Scoring System (IPSS) for childhood myelodysplastic syndrome (MDS) and juvenile myelomonocytic leukemia (JMML).

The International Prognostic Scoring System (IPSS) for myelodysplastic syndrome (MDS) is based upon weighted data on bone marrow (BM) blast percentage, cytopenia, and cytogenetics, separating patients into four prognostic groups. We analyzed the value of the IPSS in 142 children with de novo MDS and 166 children with juvenile myelomonocytic leukemia (JMML) enrolled in retro- and prospective studies of the European Working Group on childhood MDS (EWOG-MDS). Survivals in MDS and JMML were analyzed separately. Among the criteria considered by the IPSS score, only BM blasts <5% and platelets >100 x 10(9)/l were significantly associated with a superior survival in MDS. In JMML, better survival was associated with platelets >40 x 10(9)/l, but not with any other IPSS factors including cytogenetics. In conclusion, the IPSS is of limited value in both pediatric MDS and JMML. The results reflect the differences between myelodysplastic and myeloproliferative diseases in children and adults.

Myelodysplastic syndrome, juvenile myelomonocytic leukemia, and acute myeloid leukemia associated with complete or partial monosomy 7. European Working Group on MDS in Childhood (EWOG-MDS).

We reviewed the clinical features, treatment, and outcome of 100 children with myelodysplastic syndrome (MDS), juvenile myelomonocytic leukemia (JMML), and acute myeloid leukemia (AML) associated with complete monosomy 7 (-7) or deletion of the long arm of chromosome 7 (7q-). Patients with therapy-induced disease were excluded. The morphologic diagnoses according to modified FAB criteria were: MDS in 72 (refractory anemia (RA) in 11, RA with excess of blasts (RAEB) in eight, RAEB in transformation (RAEB-T) in 10, JMML in 43), and AML in 28. The median age at presentation was 2.8 years (range 2 months to 15 years), being lowest in JMML (1.1 year). Loss of chromosome 7 as the sole cytogenetic abnormality was observed in 75% of those with MDS compared with 32% of those with AML. Predisposing conditions (including familial MDS/AML) were found in 20%. Three-year survival was 82% in RA, 63% in RAEB, 45% in JMML, 34% in AML, and 8% in RAEB-T. Children with -7 alone had a superior survival than those with other cytogenetic abnormalities: this was solely due to a better survival in MDS (3-year survival 56 vs 24%). The reverse was found in AML (3-year survival 13% in -7 alone vs 44% in other cytogenetic groups). Stable disease for several years was documented in more than half the patients with RA or RAEB. Patients with RA, RAEB or JMML treated with bone marrow transplantation (BMT) without prior chemotherapy had a 3-year survival of 73%. The morphologic diagnosis was the strongest prognostic factor. Only patients with a diagnosis of JMML fitted what has previously been referred to as the monosomy 7 syndrome. Our data give no support to the concept of monosomy 7 as a distinct syndrome.

Mutation spectrum in patients with Wiskott-Aldrich syndrome and X-linked thrombocytopenia: identification of twelve different mutations in the WASP gene.

Twelve different mutations in the WASP gene were found in twelve unrelated families with Wiskott-Aldrich syndrome (WAS) or X-linked thrombocytopenia (XLT). Four frameshift, one splice, one nonsense mutation, and one 18-base-pair deletion were detected in seven patients with WAS. Only missense mutations were found in five patients diagnosed as having XLT. One of the nucleotide substitutions in exon 2 (codon 86) results in an Arg to Cys replacement. Two other nucleotide substitutions in this codon, R86L and R86H, have been reported previously, both giving rise to typical WAS symptoms, indicating a mutational hot spot in this codon. The finding of mutations in the WASP gene in both WAS and XLT gives further evidence of these syndromes being allelic. The relatively small size of the WASP gene facilitates the detection of mutations and a reliable diagnosis of both carriers and affected fetuses in families with WAS or XLT.

Natural killer (NK)-cell activity and antibody-dependent cellular cytotoxicity (ADCC) in primary preleukemic syndrome.

In 13 patients with a multi-parameter based diagnosis of primary acquired preleukemic syndrome (PPS), natural killer (NK) cell activity and antibody-dependent cellular cytotoxicity (ADCC) were investigated on peripheral blood mononuclear cell (MNC) fractions. In all but two patients a defective NK activity was found. Lymphocyte-monocyte mixture experiments demonstrated that this was not due to suppressor monocytes. Furthermore, NK activity was defective when both myeloid and non-myeloid target cell lines were used. Addition of human leukocyte interferon to the NK cultures augmented the cytotoxicity, which exhibited the same kinetics as that of normal controls, but NK activity levels remained subnormal. These data strongly indicate that the decreased NK activity seen in the patients is due to a decreased number of circulating NK cells. In contrast ADCC was within the normal range both when MNC suspensions as well as when purified peripheral blood lymphocytes were used as effector cells thus ruling out subnormal lymphocyte ADCC masked by the presence of monocyte ADCC. These results demonstrate that PPS patients have a selective NK defect with an intact lymphocyte ADCC function. Whether this defect will prove to be valuable in the assessment of a malignant transformation in a given patient will await further longitudinal NK studies and clinical follow-up of the patients.

13-cis retinoic acid treatment of myelodysplastic syndromes.

Of eight patients with primary myelodysplastic syndrome (MDS) treated with Roacutane (13-cis retinoic acid, Roche, Basel, (13-RA)) 20 mg/m2 for 6 weeks and an additional 100 mg/m2 for 4 weeks (3 patients), 4 responded either with a slight increase in peripheral blood neutrophil count or a decrease in myeloperoxidase deficient neutrophils. In agar cultures 2 patients showed a concurrent increase in growth of day 11 colonies and clusters. In 2 of the patients a decrease in the number of immature bone marrow cells positive for the myeloid antibody anti-My7 was observed. Only minor alterations were seen in natural killer cell activity. In 4 patients showing clonal chromosomal abnormalities before treatment a disappearance of minor clonal abnormalities during treatment was observed, and in 3 chromosomal abnormalities reappeared after cessation of therapy. Even though the overall impact of 13-RA on the hematopoietic system was minor, the increase in myeloperoxidase normal granulocytes in the blood and the decrease in My7 positive cells and in clonal chromosomal abnormalities warrants further interest in this agent as a treatment modality in MDS. The side effects, especially experienced by the patients receiving 100 mg/m2, were, in spite of symptomatic treatment, of such a degree that only low dose treatment (10-20 mg/m2) administered for prolonged periods of time (3-6 months) would seem recommendable.

Parvovirus B19 infection infrequently involved in children and adults with myelodysplastic syndrome.

Parvovirus B19 infection has occasionally been reported to mimic myelodysplastic syndrome (MDS) or to cause worsening of anemia in MDS. We examined the presence of parvovirus DNA in a series of children (n=19) and adults (n=39) with a diagnosis of MDS. The series of adults included only refractory anemia (RA) and RA with ring sideroblasts (RARS). Investigation for parvovirus B19 DNA in bone marrow cells was performed employing the nested form of the polymerase chain reaction (PCR). Only a 51-year-old male with RA tested positive for parvovirus DNA. Serial examinations demonstrated the disappearance of parvovirus DNA from the bone marrow. We conclude that parvovirus infection may only rarely mimic MDS or be a superimposed infection in childhood MDS or in RA and RARS in adults.

Another case of myelodysplastic syndrome with a chromosome mode in the tetraploid range.

A patient with a myelodysplastic syndrome and a near-tetraploid karyotype has been reported earlier. We describe another myelodysplastic patient. The karyotype is pseudotetraploid and shows only minor deletions.

Specific minor chromosome deletions consistently occurring in myelodysplastic syndromes.

Forty-two patients with refractory anemia with or without sideroblasts have been investigated cytogenetically one to nine times (mean, 3) over a period of 1-36 months (mean, 16). The initial investigation showed numerical and/or major structural abnormalities [t(3;3), 5q-, -7, or 7q-, 11q-] in nine patients (21%). In addition, minimal terminal deletions were observed in 2p, 8p, 9p, 11p, 12p, 17p, 17q, 20q, and Xp. The detection of these deletions, which have not been reported earlier, was due to consistent application of the high resolution technique, G-banding without trypsin, and metaphase photography on large size negatives. Each deletion occurred as a clone on one or more occasions in 1-17 patients (mean, 7). One or other clonal minimal deletion was observed in 32 patients (76%). Preliminary indirect evidence indicates that alone or together with other factors the deletions promote leukemic transformation of refractory anemia.

Acute leukemia cytogenetics: an evaluation of combining G-band karyotyping with multi-color spectral karyotyping.

We have, during a 12-month period, evaluated the adjuvant effect of combining G-band karyotyping and multi-color spectral karyotyping (SKY) in acute leukemia patients. Forty-four cases were evaluated; fewer cases than those routinely analyzed by G-band cytogenetics had mitoses left for SKY analysis. Of the 44 patients, 35 were acute myeloid leukemia (AML) and 9 acute lymphatic leukemia (ALL) cases. Twenty-seven of 35 AML and 7 of 9 ALL patients had an abnormal G-band karyotype. Thirteen of these 34 abnormal cases had a simple clonal chromosome aberration, and the remaining 21 cases had a complex karyotype. The SKY confirmed the simple karyotype in 11 and in 7 with a complex karyotype. In 13 of the cases with a complex karyotype, ambiguous structural aberrations were classified, in 6 of these, SKY disclosed cryptic translocations. Thus, SKY either extended or confirmed G-band karyotypes in 31 of 34 analyzed abnormal cases. Cases where SKY did not reveal the abnormal clone showed only few abnormal mitoses by G-banding (2/23, 2/25, and 4/27). Additional or confirmatory information was therefore obtained in 91% of analyzed cases, and SKY proved to be a valuable additional tool for hematologic cytogenetics.

Specific minor chromosome deletions in myelodysplastic syndromes: clinical and morphologic correlations.

Thirty-four patients with myelodysplastic syndrome (MDS) subtypes refractory anemia (RA) and RA with ringed sideroblasts (RA-S) (26 and eight patients, respectively) were investigated for clinical and morphologic significance of the most frequently occurring minor chromosome deletions [del(17)(p12), del(8)(p22), del(2)(p24), and del(9)(p22)]. The occurrence of 17p- was statistically significantly related to a low initial bone marrow cellularity (p = 0.01) and severe granulocytopenia (p = 0.05). A diagnosis of RA was seen more frequently among patients with 17p-, also. 17p- alone was not related to progression to RA with an excess of blasts (RAEB). The occurrence of 8p- was statistically significantly related to a higher initial frequency of bone marrow myeloblasts (p = 0.05), but not to bone marrow cellularity or initial granulocytopenia. 8p- alone was not related to initial diagnosis, but a statistically significant relation to progression to RAEB was found (p = 0.05). 2p- was related to progression to RAEB, also (p = 0.02), but not to any of the other investigated parameters. No significant relations between the occurrence of 9p- and other parameters were demonstrated. The simultaneous occurrence of 17p- and 8p- was also statistically significantly related to progression to RAEB (p = 0.02). These relationships suggest that 17p- is involved in the development of bone marrow and peripheral blood granulocytopenia and that 8p-, and possibly 2p-, interferes with differentiation of primitive granulocyte precursors and, thus, play a part in the process leading to RAEB and acute myeloid leukemia.

Chromosome alterations in renal cell carcinoma of childhood may correspond to aberrations in adults.

A 5.5-year-old girl with renal cell carcinoma and chromosomal abnormalities is described. Morphology was diagnostic of an adenopapillary renal cell carcinoma. The karyotype was 57, XX, +X, +2, +3, +4, +7, +12, +13, +16, +17, +20, +21[8]/58,idem, +17[17]. This karyotype has not previously been described in the rare cases of childhood renal cell carcinoma. It is similar to the karyotypes described in adults of the same morphologic subtype. This poses the question whether different types, from a genotype point of view, of renal cell carcinoma exist in childhood.

A case of childhood acute myeloid leukemia associated with inversion (7)(p21q31).

We describe a case of acute myeloid leukemia in a 2 1/2-year-old boy presenting with a mediastinal tumor causing respiratory distress, and lymph node enlargement in the cervical and inguinal regions. Apart from myeloid markers CD13 and CD33, blast cells also expressed stem cell marker CD34 and megakaryocytic marker CD61. Cytogenetically, inv(7)(p21q31) was found in 9/25 and 15/25 analyzed metaphases from short-term cultures of lymph node and bone marrow cells, respectively. The patient is in continued complete remission 26 months post diagnosis. The case demonstrates that chromosome aberrations other than inv(16), t(8;21), and t(9;11) may be associated with extramedullary disease, and that not all chromosome 7 aberrations are prognostic adverse findings.

Chromosome aberrations in adult Hodgkin disease in a Danish population-based study.

During a 6-year period, 31 patients with Hodgkin disease (HD) were analyzed for chromosome aberrations on lymphoid tissue. We obtained metaphases in 87% (27/31). The number of cells analyzed per case ranged from 17 to 31 (median 25), and the number of abnormal mitoses was between 1 and 17 (median 6). Chromosome aberrations were found in 59% (16/27). Numerical aberrations involved all chromosomes. The most frequently gained chromosomes were numbers 2 and 9, and the most frequently lost were numbers 10, 16, 21, 22, and X. Chromosomes most frequently involved in structural aberrations were numbers 1 and 6. The most frequent subgroups were nodular sclerosis (NS) (n = 16) and mixed cellularity (MC) (n = 10). Six NS patients and 8 patients with MC showed an abnormal clone. For the NS patients with an abnormal karyotype, 4 of 6 had a gain of chromosome 2, and all had structural aberrations of chromosome 1. Of the 6 MC patients, where a partial analysis was possible, 4 had a gain of chromosome 9, 2 had structural aberrations involving chromosome 6 and 2 of chromosome 14. In 1 case a translocation normally associated with non-Hodgkin lymphoma (NHL) was found (t[11;14]), whereas other translocations characteristic of NHL, such as t(8;14), t(14;18), and t(2;5) were not observed. A review of the literature on cytogenetic investigations in HD performed on lymphoid tissue showed that the most frequently gained or lost chromosomes were 1, 2, 5, 9, and 12 for NS and 2, 5, and 9 for MC. The most frequently affected chromosomes in structural aberrations were 1 and 6 for NS, and 1, 7, and 14 for MC. Involvement of chromosome 1, 6, and 14 in structural aberrations is characteristic of lymphoid neoplasms, as are the most frequently involved bands (1p36, 6q21-q26, 14q11, and 14q32) further supporting a B- or T-cell origin of the neoplastic cell in HD. The high hyperploidy seen in HD is not a frequent observation in NHL. Although certain chromosome aberrations seem to be characteristic of HD as opposed to NHL, specific nonrandom aberrations have yet to be identified. The rather low number of abnormal mitoses found in most HD cases underlies the importance of analyzing a large number of metaphases.

Cytogenetic aberrations in adult acute lymphocytic leukemia: optimal technique may influence the results.

The aim of the present study was to analyse the distribution of cytogenetic aberrations in adult ALL in a population based material and compare the results with literature data. Forty-one patients were diagnosed during a 12-year period. The age varied between 14 and 82 (mean 37, median 32). Thirty-two patients were cytogenetically investigated and in all cases analysable metaphases were obtained (range 10-29, mean 24, median 25, success rate: 100%). Nine (28%) patients had a T-phenotype and 23 (72%) had a pre-B phenotype. High hyperdiploidy was found in four patients (13%). Hypodiploidy was found in 5 patients (16%), 10 (31%) had a pseudodiploid chromosome mode and four (13%) showed low hyperdiploidy (chromosome mode 47-51). Chromosomes 10 and 18 were most frequently involved in numerical aberrations. Structural aberrations most frequently involved chromosomes 6, 9 and 22. t(9;22) was seen in six cases (19%), del(6q) in five cases (16%) and der(9p) in five cases (16%). High hyperdiploid clones, which are associated with a favorable prognosis, were found with the same frequency as in other studies. The frequency of t(9;22) was 19% in our study, others have found frequencies between 11% and 30%. Compared to previously published studies our patients with t(9;22) were younger. Furthermore, those with del(6q) were older, showing a median age equivalent to the patient group as a whole. The differences between our data and previously published studies may be explained by population-based derived data and especially by an optimal technique in obtaining metaphases.

Ectopic pregnancy: histopathology and assessment of cell proliferation with and without methotrexate treatment.

OBJECTIVE: To evaluate tubal morphology, trophoblast proliferation, and inflammatory reaction in response to methotrexate (MTX) treatment of ectopic pregnancy (EP). DESIGN: Nonrandomized controlled study. SETTING: Academic hospital. PATIENTS: Archival specimens from 10 EP unsuccessfully treated with MTX and 10 cases primarily treated by surgery. INTERVENTIONS: Ki67/hCG and Ki67/human placental lactogen double immunohistochemical methods were used to examine trophoblastic spread, placentation, hormone production, decidualization, vascular invasion, hemorrhage, rupture, and proliferative index of the cytotrophoblast. B and T-lymphocyte responses were evaluated by CD3 and CD20. RESULTS: Trophoblastic spread and placentation were confined to the tubal mucosa after MTX treatment, whereas invasion of the muscularis and subserosa was common in the controls. The proliferative index was reduced (19 percent versus 93 percent), although a high proliferative index was found in two of three cases complicated by rupture. Polar proliferation of Ki67-positive cytotrophoblast toward the implantation site was abolished in MTX-treated cases. Decidual reaction was not observed. No correlation was observed between the above-mentioned findings and gestational age, level of beta-hCG, dose of MTX, or interval to surgery. CONCLUSION: Trophoblastic spread, differentiation, and invasion were compromised by MTX treatment. Methotrexate seems to decrease cytotrophoblast proliferation. Whether a missing decrease in proliferation index reflects treatment failure awaits a larger population-based study.

[Cytogenetic investigation of kidney tumors. A supplement to conventional diagnosis]. / Cytogenetisk undersøgelse af nyretumorer. Et supplement til konventionel diagnostik.

Cytogenetic investigation in renal cell tumours may supplement morphological and immunohistological investigation. Cytogenetic aberrations may be an adjuvant in several situations: 1. For distinction between renal cell adenoma (RCA) and renal cell carcinoma (RCC). 2. For identification of specific genetic diseases with an increased incidence of RCC. 3. As support for a diagnosis of Wilms Tumour (WT) in children and for identification of genetic diseases with a higher incidence of WT. 4. As a possible aid in the distinction of RCA and RCC from rare kidney tumours.