Meiotic origin of trisomy in neoplasms: evidence in a case of erythroleukaemia.

Trisomic cells in neoplasms may represent abnormal clones originated from a tissue-confined mosaicism, and arise therefore by a meiotic error. We report on a 16-month-old child with erythroleukaemia (AML-M6), whose marrow karyotype at onset was 48,XX,del(13)(q12q14),del(14)(q22q32),+21,+21. The parental origin of the supernumerary chromosomes 21 was investigated by comparing 10 polymorphic loci scattered along the whole chromosome on the patient's marrow and her parents' leukocytes. Three loci were informative for the presence of three alleles, two of which were of maternal origin; two further loci showed a maternal allele of higher intensity. Lymphocytes and skin fibroblasts showed a normal karyotype, and molecular analysis on leukocytes at remission, buccal smear and urinary sediment cells consistently showed only one maternal allele, whereas neonatal blood from Guthrie spot showed two maternal alleles as in the marrow. An accurate clinical re-evaluation confirmed a normal phenotype. Our results indicate that tetrasomy 21 arose from a marrow clone with trisomy 21 of meiotic origin. To the best of our knowledge, this is the first evidence that supernumerary chromosomes in neoplastic clones may in fact be present due to a meiotic error. This demonstrates that a tissue-confined constitutional mosaicism for a trisomy may indeed represent the first event in multistep carcinogenesis.

17q21-qter trisomy is an indicator of poor prognosis in acute myelogenous leukemia.

A reciprocal translocation (9;11) is often found in acute myeloid leukemia (AML), mostly of the M5a type. We report a case of a child with AML, in whom t(9;11) was observed at diagnosis as the sole structural abnormality, together with trisomies 19 and 21. The diagnosis was AML evolving from a myelodysplastic syndrome (MDS), and the blast morphology was undifferentiated. Chemotherapy failed to induce morphological remission and the patient's condition soon worsened. A subclone appeared and expanded during the course of the disease, with an additional unbalanced translocation (1;17) leading to trisomy of the long arm of chromosome 17 (17q). The data available from the literature on acquired anomalies involving 17q and our observation led us to postulate a specific link between the gain of 17q and complete chemoresistance.

Full cytogenetic characterization of a new neuroblastoma cell line with a complex 17q translocation.

Recent studies have shown that structural abnormalities of chromosome 17 resulting in gain of material are the most frequent genetic changes in neuroblastoma. We have established a new neuroblastoma cell line from a patient whose disease had evolved from stage 4s to 4, without evidence of deletion of the short arm of chromosome 1 and MYCN amplification, which are considered the most typical genetic indicators of aggressive disease. The cytogenetic study allowed a full characterization of the chromosome changes, and revealed a complex translocation of chromosome 17 leading to a derivative marker which may be described as follows: der(11)t(11;17)(p15;q12)t(11;17) (q22;q12). This resulted in a gain of part of the long arms of chromosome 17, which was recently associated with poor prognosis.

[The morphological assessment of bone marrow infiltration in neuroblastoma]. / Valutazione morfologica dell'infiltrazione midollare nel neuroblastoma.

Bone marrow biopsy is very important in diagnosis and follow-up of children affected by neuroblastoma (NB). Between June 1995 and May 1997 we studied 55 patients with NB stage 4. Specimens were obtained at the diagnosis (in 8 patients) and after chemotherapy (in 55 patients) in order to evaluate the effects of treatment on bone marrow disease. 88% of 343 biopsies were representative versus 99% of 639 aspirates. Of 8 stage 4 patients evaluated at diagnosis, 15/16 biopsies versus 9/15 aspirates were positive. Following chemotherapy, out of 298 evaluable sites examined, 111 biopsies versus 30 aspirates (37 versus 10%) were positive. Of 111 positive biopsies 53 showed a focal pattern (35 differentiated, 18 undifferentiated), while 51 showed a diffuse pattern (18 differentiated, 40 undifferentiated). Our results confirm previous literature data indicating a better efficacy of histology versus morphology in detecting residual bone marrow disease (especially in case of focal differentiated pattern). The recent introduction of a specific monoclonal antibody, called anti-GD2, has improved our capacity to detect minimal residual disease in patients' bone marrow. The inclusion of anti-GD2 immunohistochemistry in our evaluation will possibly increase our overall sensitivity to detect minimal residual disease and may provide information capable to direct the physician's decision into a more rational patient's treatment.

[The identification of minimal residual disease in the bone marrow and peripheral blood in neuroblastoma. The prognostic and therapeutic implications]. / Identificazione della malattia residua minima nel midollo e nel sangue periferico nel neuroblastoma. Implicazioni prognostiche e terapeutiche.

A highly sensitive and specific methodology to detect neuroblastoma cells in the bone marrow and peripheral blood of children with neuroblastoma is of critical importance for proper staging and treatment of these patients. In addition, patients with bone marrow infiltration at diagnosis need to undergo regular investigation to measure the effectiveness of chemotherapy (so called "in vivo" purging). Finally, the evaluation of autologous stem cells taken from bone marrow or peripheral blood is necessary to rule out or minimise the possibility of reinfusing tumor cells to the patient following myeloablative therapy. The authors provide a "state of the art" data on this complicated issue and give their preliminary results of their own experience, mainly concerning the immunocytological methods.

Lipoblastoma: a case with t(7;8)(q31;q13).

Lipoblastoma is a rare benign adipose tumor which, in all of the cases so far described, presents an involvement of chromosome 8 in the region 8q11-13. We hereby report the results of the second case of lipoblastoma studied by fluorescence in situ hybridization (FISH), in a 13-month-old boy. An abnormal karyotype 46,XY,t(7;8)(q31;q13) was found in 90% of the metaphases examined, in agreement with the previously reported observations. We suggest the region 8q11-13 may contain a relevant locus for lipoblastoma origin.

Massively diffuse multifocal granulocytic sarcoma in a child with acute myeloid leukemia.

A case of granulocytic sarcoma in an 8-year-old boy with acute myeloid leukemia and t (8; 21) is reported. The case is of interest due to massive extension of the tumor, which may raise different diagnostic difficulties with other solid tumors such as lymphoma, Ewing sarcoma, and soft tissue sarcoma. Furthermore, the tumor was localized in some sites, such as the parotid region and peripheral nerves, which are not usually involved in granulocytic sarcoma. The case points out the diagnostic difficulties with this kind of tumor and appears to contribute to the identification of a subgroup of acute myeloid leukemia with peculiar features, such as M2 morphology with Auer rods, t (8; 21), granulocytic sarcoma and a poor prognosis.

Prognostic relevance of ALL-1 gene rearrangement in infant acute leukemias.

We and others have recently reported a high frequency (70-80%) of ALL-1 (MLL, HRX, HTRX) gene rearrangements in infants with acute leukemias (AL) aged less than 1 year. Preliminary observations in limited series also suggested that ALL-1 gene configuration is an important prognostic factor in this leukemic subset. We have now extended our study to a series of 45 AL patients aged between 0 and 18 months. The genomic configuration of ALL-1 in leukemic DNAs was determined by Southern blot hybridization and correlated with biological and clinical features at presentation, as well as with treatment outcome. Twenty-nine out of 45 (64%) patients showed ALL-1 rearrangements, including 4/11 (36%) infants aged between 13 and 18 months. Considering morphological types, 24/38 cases with acute lymphoblastic leukemia and 5/7 patients with acute myeloid leukemia showed ALL-1 rearrangements. The features more frequently found in association with ALL-1 rearrangements were hyperleukocytosis (P < 0.007) and CD19+/CD10- blast immunophenotype (P < 0.02). ALL-1 status was an independent prognostic marker of event-free survival (EFS) in a multivariate model including age, sex and WBC count, and maintained its statistical significance when FAB morphology was considered in the analysis by including AML patients. Considering the ALL cases the actuarial EFS was 57 and 9% for infants with germline and rearranged ALL-1 configuration, respectively (P = 0.008). A high frequency of ALL-1 gene alterations in infant AL is confirmed by this study. In addition, our results emphasize the need for extending the analysis of ALL-1 gene status to infants with AL aged > 12 months. We show that this genetic lesion is the most important variable negatively affecting prognosis in a multivariate model including other known risk factors. This latter observation should influence the choice of risk-adapted treatment strategies in this AL subset.

Evaluation of minimal residual disease in high risk childhood acute lymphoblastic leukemia using an immunological approach during complete remission. AIEOP Cooperative Group for Immunology of Acute Leukemias.

BACKGROUND: Sensitive methods for detecting residual disease may complement conventional morphology while monitoring the response to treatment in leukemia patients. METHODS: We studied minimal residual disease (MRD) by selecting via a colony assay a peripheral blood (PB) cell population enriched in putative malignant cells and detecting occult leukemic cells by double immunologic analysis performed on colonyforming cells (CFC). Using this combined technique we assayed the PB of high risk children with acute lymphoblastic leukemia (ALL) in order to demonstrate possible differences in "the residual tumor cell burden" among leukemia patients and to correlate these with a 3-year clinical follow-up. RESULTS: In all 22 patients positive results were obtained for up to 18 months following induction chemotherapy at times of apparent hematologic remission. Common ALL (cALL) patients exhibited a mean of 9.6% cAlla+ cells (range: 2% to 30%), whereas cALL antigen (cALLA) and cALLA/Tdt or CD1a/Tdt combination were never found in the colonies derived from healthy individuals. Six out of 22 cALL patients expressed a mean of 16.5% cALLA+/Tdt+ CFC (range: 2% to 35%). Five T-ALL children presented a mean of 24% CD1a/Tdt+ cells (range: 8% to 44%). Extensive follow-up indicates a correlation between the percentage of CFC Tdt+/lymphoid marker+ cells (more than 10%) and subsequent clinical relapse. In one patient relapse occurred after 16 months with a dramatic increase in the number of leukemic cells. In contrast, the decline in malignant cells, observed in two cases, predicted a favourable course. Five patients tested before autologous bone marrow transplantation (ABMT) presented high number of positive cells and relapsed at various times. CONCLUSIONS: We conclude that this approach to the study of MRD could be valuable in monitoring the efficacy of chemotherapy, as well in evaluating the quality of purged marrow.

Acute myeloid leukemia after single-agent treatment with etoposide for Langerhans' cell histiocytosis of bone.

The first case of secondary leukemia (FAB M3 microgranular variant) after single-agent chemotherapy with etoposide is described. The peculiar morphology and the absence of previously described cytogenetic abnormalities make this case of interest and emphasize the need for further study of epipodophyllotoxin-related leukemia.

Acute lymphoblastic leukemia in Noonan syndrome: report of two cases.

Only two cases of Noonan Syndrome (NS) associated with tumor have previously been reported. The authors describe two new cases of NS with acute lymphoblastic leukemia (ALL), which were part of a series of 370 consecutive ALL untreated patients.

B-cell acute lymphoblastic leukemia (B-ALL): a report of 17 pediatric cases.

BACKGROUND AND METHODS: B-cell acute lymphoblastic leukemia (B-ALL) presents FAB L3 morphology and surface Ig, CD19, CD20, CD24. This pattern may show some morphological and immunological heterogeneity. Seventeen pediatric cases of B-ALL at onset, treated in twelve AIEOP Centers (Italian Association for Pediatric Hematology and Oncology), are presented. RESULTS AND CONCLUSIONS: Clinical and hematological features were characterized by low WBC counts at presentation, high M/F ratio, older age and association with extramedullary involvement. The overall survival curve at 78 months is 40%. All patients showed blasts positive for surface Ig (sIg), DR, CD19, and CD24. Ten/17 cases presented the classical features of B-ALL: FAB L3 morphology, sIg+ restricted to light chains, CD20+, cytoplasm mu (c mu)-, CD10-, TdT-. The remainder showed some differences in this pattern, such as non-L3 morphology (3 cases), absence of CD20 (3 cases), CD10+ (4 cases), TdT+ (3 cases), c mu+ (1 case), lack of surface light chains (1 case). This rare ALL subset seems to be characterized by a high phenotype heterogeneity, indicating various degrees of differentiation.

Granular acute lymphoblastic leukemia in children. "Aieop Cooperative Group for Cytology of Acute Leukemias".

BACKGROUND: Granular acute lymphoblastic leukemia (ALL) is a rare morphological variant of ALL, characterized by cytoplasmic azurophil granules or inclusions, positive for aspecific esterase and acid phosphatase, with heterogeneous features at the ultrastructural level. METHODS: In an attempt to determine whether the presence of granules or inclusions marks a biologically distinct variety of ALL with peculiar clinical features, a prospective morphological review was undertaken of children entering AIEOP protocols for ALL in the period from 1985 to 1989. RESULTS: Of 531 cases examined, 16 (3%) were found to have greater than 1% granular bone marrow blasts, with 7 cases (1.3%) having greater than 10%. The presence of granules or inclusions was associated with the immunophenotype of "common" ALL. There was no clear association with FAB type L1 or L2 nor with particular clinical or hematological findings at presentation. Complete remission was achieved in all cases; one patient died of infection in remission at 3 months and 2 patients relapsed after 12 and 32 months, respectively, while the others are still in remission after a minimum follow-up of 24 months. CONCLUSIONS: In conclusion, granular morphology seems to have no prognostic importance in children ALL.

Myeloablative therapy and unpurged autologous bone marrow transplantation for poor-prognosis neuroblastoma: report of 34 cases.

From October 1984 to November 1987, 34 patients aged from 1 year 1 month to 7 years 7 months with resistant or relapsed neuroblastoma (NB) (group 1, 10 patients), unselected disseminated NB (group 2, 14 patients), or selected disseminated NB (group 3, 10 patients) received myeloablative therapy (MAT) followed by unpurged autologous bone marrow transplantation (ABMT) at the end of an intensive protocol, which included high-dose chemotherapy and surgery to the primary tumor. Median time from diagnosis to MAT and ABMT was 6 months (5 months from last relapse to MAT and ABMT in the relapsed patients). The MAT regimen included vincristine, fractionated total body irradiation (TBI), and melphalan. Seventeen patients were grafted in complete remission (CR), five in very good partial remission (VGPR), 10 in partial remission (PR), and two in progressive disease (PD). The acute toxic death rate was 2.9%. The overall progression-free survival was 29%. The median progression-free survival was 20 months for the 17 patients grafted in CR, 6 months for the five patients grafted in VGPR, and 12 months for the 10 patients grafted in PR.

Cytogenetics of infantile leukemias and its correlations with bio-clinical features. The "G. Gaslini" Children's Hospital experience over a 9-year period.

BACKGROUND AND METHODS: Infantile leukemia is a rare disorder, and few cytogenetic studies have been performed on this condition. RESULTS AND CONCLUSIONS: The authors present the cytogenetic analyses performed on 14 cases of infantile leukemia. The most frequent chromosomal changes are rearrangements involving 11q (4 cases) and gains of one or more chromosomes 21. Patients with chromosomal rearrangements show a worse prognosis than those with only hyperdiploidy or a normal karyotype, although the difference was not statistically significant due to the small size and short median follow-up.

New clinical aspects of Pearson's syndrome. Report of three cases.

We describe 3 patients affected by Pearson's syndrome, presenting anemia, exocrine pancreas failure, and skeletal abnormalities; insulin-dependent diabetes mellitus arose in two cases during the course of the disease. Bone marrow dysplasia and exocrine pancreas failure are also reported in Shwachman's syndrome; the two forms differ in bone marrow morphology. The clinical pattern of Pearson's syndrome can be so polymorphic as to increase the difficulties of differential diagnosis with Shwachman's syndrome.

Granulocytic sarcoma presenting as an isolated mediastinal mass. A difficult diagnostic problem.

An unusual case of granulocytic sarcoma presenting in an 8-year-old boy as an isolated mediastinal mass, preceding by 7 months the development of acute myeloid leukemia, is reported. The patient was initially treated for lymphoblastic lymphoma, with poor response. We recommend that in such cases, full histocytochemical and immunological characterization of the tumor should be performed.

A short-term in vitro drug sensitivity assay in pediatric malignancies.

A short-term in vitro chemosensitivity test has been applied to 131 specimens from 109 children with various malignancies. The clinical outcome was correlated with in vitro percentage inhibition (PI) of DNA synthesis by the drug tested. In 62 correlations, PIs of responsive and of resistant patients differed significantly, with a cut-off value of 37%. The test predicted clinical resistance in 53/54 cases, with a specificity of 98%, and clinical response in 8/8 cases, with a sensitivity of 100%. This test can be useful particularly in predicting chemoresistance in relapsing patients, to avoid unnecessary toxicity.