Lymphoblastic Morphology Research Articles

Heterogeneity of Presenting Features and Their Relation to Treatment Outcome in 120 Children With T-Cell Acute Lymphoblastic Leukemia

Presenting features of 120 consecutive children with T-cell acute lymphoblastic leukemia (ALL), representing 15% of all patients diagnosed as having ALL during the study period, were analyzed to determine relationships with treatment outcome. Patients' ages ranged from 1.7 to 18.8 years (median, 10.3 years) and their leukocyte counts from 1.7 to 1,070 x 10(9)/L (median, 100 x 10(9)/L). Central nervous system (CNS) leukemia was present in 12.5% of the cases, a mediastinal mass in 61%, and L2 lymphoblast morphology in 32%. A relatively high proportion of cases, 26%, had normal karyotypes at presentation. Of the cases tested, membrane CD1 expression was found in 38% of cases, CD3 in 33%, CD4 in 50%, CD5 in 94%, CD8 in 55%, and CD10 in 35%. Four presenting features were found to confer an increased risk of treatment failure: age greater than or equal to 15 years, L2 lymphoblast morphology, abnormal karyotype, and membrane CD3 expression. This study illustrates the heterogeneity of presentations of childhood T-cell ALL and suggests that the relative importance of risk factors in ALL differs according to immunophenotype and treatment strategy.

Thrombocytosis as a presenting feature of acute lymphoblastic leukemia in childhood.

To determine the incidence of thrombocytosis at presentation in acute lymphoblastic leukemia (ALL), medical records of all children diagnosed at the Children's Hospital of Pittsburgh from 1980 to 1987 were reviewed. Out of 217 such patients, 7 (3.2%) had platelet counts greater than 400,000/mm3. All of the seven were boys compared with a male:female ration of 1.4:1 in the entire ALL population. Other than sex, no characteristics were clearly associated with thrombocytosis, including white blood cell count, hemoglobin, lymphoblast morphology, and immunologic or chromosomal markers. Apart from ALL, no inflammatory or infectious process which might have caused a thrombocytosis, was detected in any of these patients. The period of induction therapy was notable for the preservation of platelet counts greater than 20,000/mm3 in all patients. However, of the seven children with thrombocytosis, two had major induction complications: one, a cavernous sinus thrombosis; and the other, gastrointestinal bleeding with duodenal perforation. We conclude that thrombocytosis at diagnosis can be seen in children, particularly boys, with ALL. Based on small numbers, this group of patients may be at risk for major events during induction therapy. Large numbers, longer follow-up, and platelet function studies on similar patients will be of interest.

Contributions of host and donor T cells to the inflammatory process in murine lymphocytic choriomeningitis

The severe inflammation characteristic of the infection of adult mice with murine lymphocytic choriomeningitis virus (LCMV) is induced earlier in unsuppressed. virus-infected recipients by the adoptive transfer of class I MHC-compatible, CD4 − CD8 + LCMV-immune spleen cell populations. The time to onset of fatal LCM may also be slightly diminished, though not to the extent that would be expected from the enhanced kinetics of the extravasation of cells into cerebrospinal fluid. The development of symptoms is thus not solely related to the magnitude of the inflammatory process. The majority of the T lymphocytes in the inflammatory exudate are of host origin and have the size characteristics of resting cells, while the minority population of donor T cells show more of a lymphoblast morphology. The findings are consistent with the idea that relatively few CD8 + virus-immune effectors trigger an inflammatory process which consists largely of secondarily recruited host T cells and monocyte/macrophages.

Childhood acute lymphoblastic leukemia.

Acute lymphoblastic leukemia accounts for 80% of leukemia in children. The exact cause is unknown, but some genetic, immunologic, viral, and environmental factors have been implicated. Symptoms at the time of diagnosis frequently include fever, bleeding, fatigue, and irritability. Initial white blood cell count and patient age at diagnosis are the most reliable indicators of prognosis. Acute lymphoblastic leukemia is a heterogenous disease. Lymphoblast morphology, immunologic markers, enzyme abnormalities, cytogenetic findings, and staining characteristics in conjunction with clinical characteristics allow classification into risk groups. Appropriate therapy for each risk group is based on these parameters. Combination chemotherapy administered alone or with additional chemotherapy or radiotherapy to sanctuary sites is the principal modality for treatment of ALL. Optimal therapy for relapse has not yet been determined, but for patients with appropriate donors, allogeneic bone marrow transplant is promising. Common complications of chemotherapy include tumor lysis syndrome, myelosuppression, and other problems such as gastrointestinal toxicity, neurotoxicity and cardiac toxicity. Significant late effects of chemotherapy include neurological impairment ranging from learning problems to leukoencephalopathy and a possible increased risk of second malignancy. Complete remission is achieved in 95% of children with acute lymphoblastic leukemia, and more than 55% will continue to be in complete remission at five years. Optimal CNS prophylaxis, effective treatment of relapse, and adjustment of therapy to minimize acute and late adverse effects are a continuing challenge. With improved understanding of biologic factors, and development of more specific therapy for each subgroup, children with acute lymphoblastic leukemia should enjoy a better long term outcome.

Changing manifestations of a chronic feline haematopoietic proliferative disease during immunotherapy with staphylococcal protein A

A cat with feline leukaemia virus-associated malignant disease was treated by ex vivo immunoadsorption using staphylococcal protein A coated filters. During the 12-week course of treatment, the morphological manifestations of the haematopoietic disease showed a progressive transition from erythroid to myeloerythroid to myeloid predominance, and the disease was preceded by and associated initially and terminally with a blast transformation of lymphoblastic morphology. Necropsy revealed massive meningo-cerebral, as well as hepatic, renal, myeloid, lymphoid, peritoneal and pelvic infiltrations largely consisting of lymphoblastic cells. Evidence of myeloid and erythroid diffentiation was present in all the infiltrates. The several possible bases for this shift of morphological expression are considered.

Clinical relevance of lymphoblast biological features in children with acute lymphoblastic leukemia.

Improvements in therapy for childhood acute lymphoblastic leukemia (ALL) have led us to reevaluate the prognostic significance of lymphoblast characteristics at diagnosis. From application of univariate and multivariate statistical methods, we determined the relationship of five blast cell features to treatment outcome in 250 patients who were enrolled in two clinical trials at this center from May 1979 through April 1982. Karyotype ploidy, lymphoblast morphology, and immunophenotype were each significantly related to prognosis as measured by time to failure, while periodic acid-Schiff reactivity and glucocorticoid receptor number lacked prognostic implication for this patient population. In addition, clinical features of initial WBC count, age, and race were also significant independent variables in predicting treatment response. By multivariate analysis, both ploidy and morphology contributed prognostic information to a clinical model based on WBC count, age, and race. If the model was adjusted for impact of ploidy, however, French-American-British morphology no longer contributed additional prognostic information. Our findings suggest that many traditional biological features used to estimate prognosis in ALL can be discarded in favor of clinical features (leukocyte count, age, and race) and cytogenetics (ploidy) for planning of future clinical trials.

Immunologic, morphologic and chromosomal characterization of a cell line (TC78) established from a child with acute lymphoblastic leukemia

We characterized a cell line established from bone marrow cells from a child with acute lymphoblastic leukemia. This cell line, TC78, had lymphoblastic morphology and was cytoplasmic peroxidase and esterase negative. The cells did not have T- or B-cell properties such as E- or EAC-rosette forming ability, reactivity with monoclonal T-cell or B2 antibodies, or immunoglobulin synthesis. We concluded that TC78 was a pre-pre B-cell line based on the following monoclonal antibody staining pattern: BA-I +, BA-2 +, cALLa +, Ia +, 2H7 + and OKB2 +. Growth in ‘Dickie’ culture and reactivity with 1G10 myeloid antibody suggested coexpression of lymphoid and myeloid characteristics. However, 1G10 expression proved dependent on culture conditions, illustrating one caveat in application of monoclonal antibodies in lineage determination.

A morphometric classification of acute lymphoblastic leukemia in children.

In order to reduce the subjective errors in subtyping leukemic lymphoblasts using the French-American-British (FAB) classification, computer-assisted morphometry was used. Bone marrow smears obtained at diagnosis from 99 children with acute lymphoblastic leukemia (ALL) were analysed by this method and compared with the subjective FAB classification. The results confirm that lymphoblast morphology, as a single variable, is a very significant predictor of survival in ALL. This computer-assisted morphometric analysis would be of great value in large-scale clinical trials in ALL.

Morphological heterogeneity in childhood B cell acute lymphoblastic leukaemia.

Considerable heterogeneity of lymphoblast morphology in childhood B cell acute lymphoblastic leukaemia has been observed. One case showed unusual monocytic features and emphasised the need for marker studies in the accurate definition of acute lymphoblastic leukaemia phenotypes. B cell acute lymphoblastic leukaemia is rare but may have been previously underestimated by morphological misinterpretation. Further information is required to determine if the different morphological features of this condition are of clinical and prognostic importance.

Unfavorable prognostic significance of hand mirror cells in childhood acute lymphoblastic leukemia. A report from the childrens Cancer Study Group.

The prognostic significance of hand mirror cells (HMCs) in childhood acute lymphoblastic leukemia was determined by quantifying the percentage of these cells in the diagnostic bone marrow aspirates of previously untreated children entered on the Childrens Cancer Study Group protocol 141. Of 664 examinable patients, 39 (5.9%) had greater than 10% HMCs, and only four (0.6%) had greater than 30% HMCs. Compared with the entire study population, a greater proportion of children with more than 10% HMCs were older than 10 years of age, had hemoglobin levels greater than 10 g/dL, and had undifferentiated lymphoblast morphology. The children with more than 10% HMCs had a higher rate of bone marrow relapse, poorer disease-free survival, and shorter survival than patients with less than 10% HMCs. By multivariate analysis, HMC morphology was an independent, unfavorable prognostic factor.

Bovine costimulator. II. Generation and maintenance of a bovine costimulator-dependent bovine lymphoblastoid cell line

Bovine peripheral blood leukocytes, activated with conconavalin A, were cultured in bovine costimulator-containing conditioned medium prepared in a totally defined, serum-free medium. A population of leukocytes subsequently grew exponentially. These bovine cells had the morphology of lymphoblasts, were negative for chloroacetate esterase, slightly positive for nonspecific esterases, and highly peanut agglutinin-positve. These data suggested that the bovine leukocytes were of the T-cell lineage and that the active factor in the costimulator-containing conditioned medium might be the bovine equivalent of Interleukin 2. A quantitative microassay, subsequently developed, revealed that the lymphoblastoid cell line was costimulator-dependent and lectin-independent. Further utilization of the microassay supported this contention and strengthened the concept of a bovine Interleukin 2-dependent bovine T-cell line: Phytohemagglutin-M, phytohemagglutinin-P, and concanovalin A induced active factor from peripheral blood leukocytes, while lipopolysaccharide, a potent inducer of Interleukin 1 in other systems, failed to induce activity; and both T-cells and macrophages were required for optimal factor activity. Finally, a means by which to optimize production of the active moiety, utilizing lymph node cells, as opposed to peripheral blood leukocytes, was examined.

Prognostic Importance of Morphology (FAB Classification) in Childhood Acute Lymphoblastic Leukaemia (ALL)

The French-American-British (FAB) classification has been proposed as a useful and uniform method of defining morphologic subsets of acute leukaemias. As part of a prospective study designed to identify subsets of children with high risk of early relapse (CCG 141), submitted bone marrow slides from 765 of 883 patients entered on study were reviewed by two morphologists blinded as to prognostic factors and treatment regimen. L1, L2 and L3 acute lymphoblastic leukaemia (ALL) comprised 85.1%, 14.1% and 0.8%, respectively, of the total population. Children with greater than 25% L2 lymphoblasts had a significantly higher relapse rate and significantly poorer survival. Results of this study indicate that as a single variable, lymphoblast morphology is a very significant predictor of survival, haematologic remission, and complete continuous remission. Multivariate analyses show that lymphoblast morphology is again significant in determining duration of survival (P = 0.048), and is of borderline statistical significance (P = 0.089) in predicting length of complete continuous remission. The FAB classification, with minor modifications, is reproducible, useful, and prognostic in childhood ALL.

Prognostic Importance of Morphology (FAB Classification) in Childhood Acute Lymphoblastic Leukaemia (ALL)

Summary. The French-American-British (FAB) classification has been proposed as a useful and uniform method of defining morphologic subsets of acute leukaemias. As part of a prospective study designed to identify subsets of children with high risk of early relapse (CCG 141), submitted bone marrow slides from 765 of 883 patients entered on study were reviewed by two morphologists blinded as to prognostic factors and treatment regimen. L1, L2 and L3 acute lymphoblastic leukaemia (ALL) comprised 85·1%, 14·1% and 0·8%, respectively, of the total population. Children with > 25% L2 lymphoblasts had a significantly higher relapse rate and significantly poorer survival. Results of this study indicate that as a single variable, lymphoblast morphology is a very significant predictor of survival, haematologic remission, and complete continuous remission. Multivariate analyses show that lymphoblast morphology is again significant in determining duration of survival (P=0·048), and is of borderline statistical significance (P=0·089) in predicting length of complete continuous remission. The FAB classification, with minor modifications, is reproducible, useful, and prognostic in childhood ALL.

Single-cell immunofluorescence assay for terminal transferase: human leukaemic and non-leukaemic cells

The characteristics of a single-cell immunofluorescence assay for terminal deoxynucleotidyl transferase (terminal transferase, TdT) is described. The data indicate that the single-cell immunofluorescence assay is highly efficient and specific for the detection of cells containing TdT. Using this assay, we have examined 124 marrow or peripheral-blood samples from 104 patients with or without haematological malignancies. Results indicate that TdT(+) cells from 6% to 100% were found in the following patients: 34/40 samples from patients with ALL at the time of diagnosis or during relapse; 2/3 patients with acute undifferentiated leukaemia; 2/3 patients with acute myelomonocytic leukaemia; 1/24 patients with acute myeloblastic leukaemia; 1/5 patients with chronic myelocytic leukaemia (CML) in blastic crisis; and 2/2 patients with diffuse lymphoblastic lymphoma. In contrast less than 1% of TdT(+) cells were found in 20 marrow or peripheral-blood samples from ALL patients in complete remission; 8 patients with CML in chronic phase; 2 patients with myeloma; 1 sample from a patient with Hodgkin's disease, peripheral-blood samples from 7 normal donors and marrow samples from 6 patients without haematological malignancies. TdT(+) cells were also found in association with cells with lymphoblast morphology. The TdT(+) cells in marrow were shown to be directly correlated with the percentage of morphological lymphoblasts, with a Spearman rank coefficient of 0·81, significant at a 0·001 level. In 2 longitudinal studies of 2 ALL patients with TdT(+) cells at diagnosis, the percentage TdT(+) cells also changed in parallel with the proportion of lymphoblasts. However, studies of 2 other patients with morphologically diagnosed ALL with < 1% TdT(+) cells at diagnosis also showed < 1% TdT(+) cells throughout the period studied, indicating a stable phenotype of blast cells in these patients. The single-cell immunofluorescence assay for TdT, which requires < 0·1% of the cells used in a conventional biochemical assay, is highly specific, and could provide a technically more efficient alternative for use in clinics as well as in experimental investigations of subpopulations of leukaemic and normal marrow cells.

Terminal Transferase: Its Evolving Role

Eventually, most patients with chronic myelocytic leukemia enter an aggressive phase of their illness, termed "blast crisis," that resembles acute leukemia except in its refractoriness to conventional chemotherapy. However, about 30 per cent of patients with leukemia in the blast-crisis phase achieve remission with rather simple chemotherapy: vincristine and prednisone. Considerable effort has been expended on defining the clinical, morphologic, cytochemical and cytogenetic characteristics of this subgroup of responsive patients. Lymphoblastic morphology and the finding of fewer than the normal diploid number of chromosomes are the two features most likely to be associated with response to vincristine and prednisone. However, . . .

Isolation and tissue distribution of type-C virus and viral components from a gibbon ape ( Hylobates lar) with lymphocytic leukemia

A seven-year-old male gibbon ape ( Hylobates lar) with malignant lymphoma and leukemia was obtained from a colony in Bermuda. Tissues obtained at necropsy were infiltrated with tumor cells to varying degrees, the most extensively involved being the kidneys, ureters, liver, lymph nodes, heart, salivary glands, and mesentery. These cells showed typical lymphoblast morphology. Type-C virus particles were abundant in the plasma and were detectable in all tissues tested. Intracytoplasmic virus was seen in some nonleukemic parenchymal cells. However, budding virus particles were observed only from the leukemic peripheral blood lymphoblasts. Tissue extracts contained viral p30, reverse transcriptase, viral RNA, and proviral DNA in amounts which generally correlated with the degree of leukemic cell infiltration. Viral markers were particularly abundant in tissue from the region of the oral cavity. Proviral DNA was found in all tissues except muscle and brain, which contained little or no leukemic cell infiltration. Replicating virus was transmitted to heterologous cells in tissue culture from many tissues, including muscle and brain. This virus, called GaLV H was classified as a member of the gibbon ape leukemia virus-simian sarcoma (simian sarcoma-associated) virus group by comparative tests of the antigenic relatedness of p30 and reverse transcriptase, and by nucleotide sequence homology of RNA from this virus and from other members of this group. These results: (a) highlight the extraordinary replication of this type of virus in gibbons; (b) further implicate this virus group in the etiology of spontaneous gibbon ape leukemia; (c) suggest that the oral route is a likely mode of virus transmission; and (d) fail to provide evidence for a genetic reservoir of virus outside of the tumor cells.

Blast crisis of chronic granulocytic leukemia: Morphologic variants and therapeutic implications

Chronic granulocytic leukemia (CGL) terminates in a disease similar to acute leukemia. Except for a study indicating an increased response rate to the drugs, vincristine and prednisone, therapy of this terminal phase has been universally disappointing. We have studied the bone marrows and clinical courses of 67 patients in the terminal phase of CGL to discern if any parameters were associated with an increased response rate or survival. The results of this study indicate that patients who have a lymphoblastic morphology or hypodiploid cytogenetics in the terminal phase respond better to treatment with the combination of vincristine and prednisone than those with myeloblastic morphology or hyperdiploid cytogenetics. Response rate and survival are significantly increased in those with lymphoblastic morphology. Recognition of the heterogeneity of the terminal phase of CGL may dictate specific therapeutic modalities.

Treatment of acute nonlymphoblastic leukemia in children with a multiple-drug protocol.

Twenty-one children with acute nonlymphoblastic leukemia (ANLL) were treated with a combination regimen consisting of arabinosyl cytosine (Ara-C), 6-thioguanine (TG), and Adriamycin, The incidence of complete remission was 74%. For consolidation, addition courses of Ara-C and TG were given, followed by L-asparaginase. The maintenance program was the same as that for the lymphoblastic type (L-2) including intrathecal methotrexate for prophylaxis of meningeal leukemia. Of the 16 who were evaluable for the duration of complete remission, six developed bone marrow relapse, one meningeal leukemia within 3-14 months after entering complete remission and one was lost to follow-up. Eight remain in complete remission for 9-72 months. In five of eight, chemotherapy has been terminated after 3 years, and all continue in remission for 11-32 months post-treatment. Although the results do not compare well to those of the lymphoblastic morphology, long-term disease-free survival can be achieved with multiple-drug intensive treatment in childhood ANLL.

Surface morphology and agglutination of lectin-treated human lymphocytes and lymphoblasts.

Two human lymphoblasts (Raji and EB3) and normal human peripheral lymphocytes were exposed to different concentrations of Concanavalin A and wheat germ agglutinin. The lectin-induced agglutination was determined and correlated with lectin-induced changes in the surface morphology of these cells as studied in a scanning electron microscope. Whenever the lectin induced high agglutinability in a cell type, it also invariably had a smoothing effect on the cell surface. In contrast, when cells did not agglutinate well with a certain lectin, their cell surface remained essentially rough (villous) after addition of the lectin. The correlation found between increased agglutinability and altered cell surface morphology upon treatment with certain lectins suggests that both phenomena result from one and the same process. Additional evidence for this postulate is presented.

Properties of a Chicken Lymphoblastoid Cell Line From Marek's Disease Tumor

Properties of a chicken lymphoblastoid cell line (MSB-1) from a Marek's disease tumor were studied. The cell line grew well at 41 degrees C in medium RPMI-1640 supplemented with 10% bovine fetal serum and had a doubling time of 8-12 hours. Cells grown in stationary suspension culture did not attach to the vessel and had the morphology of typical lymphoblasts. At 37 degrees C, the cell line grew initially but ceased to divide after several subcultures. In the subcultures maintained for 48-72 hours, 1-2% of the cells produced Marek's disease virus (MDV)-specific intracellular and mambrane antigens and contained herpesvirus particles when examined by the electron microscope. Cocultivation of these cells with duck or chicken embryo fibroblast cultures resulted in transfer of infection and production of microplaques typical of MDV. Peripheral nerve lesions and lymphoid tumors characteristic of Marek's disease were caused by inoculation of susceptible chicks with MSB-1 cells or duck cells infected with strain BC-1 of MDV recovered from the MSB-1 cell line. No specific tumors were produced at the site of inoculation, and infection was readily transmitted to cagemates. Tumors were also produced in the skeletal muscles and seemed to be largely virus induced. MSB-1 cell line was free of C-type virus particles.