Quantitative flow cytometry can predict childhood acute lymphoblastic leukaemia presenting with aplasia.

Acute lymphoblastic leukaemia (ALL) presenting as a transient pancytopenia is known to occur in children and less commonly in adults. The period of pancytopenia usually resolves after about 5-38 weeks, to be followed by overt ALL. The pathogenesis is not known and there are no specific cytogenetic abnormalities.

Quantification of P-glycoprotein in chronic lymphocytic leukemia by flow cytometry.

The P-glycoprotein (P-gp) was investigated in 40 patients with chronic lymphocytic leukemia by immunological, functional and quantitative assays. The proportion of positive cases with the anti-Pgp McAb UIC2 was 30% and increased to 64% after neuraminidase treatment (p = 0.002).

Analysis of residual disease in chronic lymphocytic leukemia by flow cytometry.

We have investigated the value of both conventional and quantitative flow cytometry to detect minimal residual disease in 21 CLL patients in remission including bone marrow histology: eight in complete remission (CR), 11 in nodular partial remission (nPR) and two in PR. The techniques used were double immunostaining with CD5 and CD19 and quantitative estimation of the number of both antigens with standard microbeads. Reference values were established on normal peripheral blood and bone marrow controls.

Atypical lymphocyte morphology: an adverse prognostic factor for disease progression in stage A CLL independent of trisomy 12.

We studied 270 patients with Binet stage A chronic lymphocytic leukaemia looking for adverse prognostic factors. In a multivariate analysis the following features were found to be risk factors for disease progression: atypical lymphocyte morphology (defined as either > 10% prolymphocytes or > 15% lymphocytes with cleaved nuclei or lymphoplasmacytoid cells); more than two karyotypic abnormalities; lymphocyte count > 30 x 10(9)/l; lymphocyte doubling time < 1 year; enlargement of one or more lymph node groups. In a univariate analysis the presence of trisomy 12 also correlated with progressive disease, but this was largely a consequence of the association between trisomy 12 and atypical lymphocyte morphology.

Mycosis fungoides and Sezary syndrome are not associated with HTLV-I infection: an international study.

Association between mycosis fungoides (MF), its leukaemic variant Sezary syndrome (SS) and the human T-cell lymphotropic virus type-I (HTLV-I) has been controversial, with the reported incidence of infection varying between 0% and nearly 100%. We studied 127 patients (85 MF, 28 SS, five Sezary cell leukaemia, four lymphomatoid papulosis, and five unspecified cutaneous T-cell lymphomas (CTCL)) originating from Europe (France, Spain, U.K.

A randomized comparison of liposomal versus conventional amphotericin B for the treatment of pyrexia of unknown origin in neutropenic patients.

One hundred and thirty-four adults and 204 children were randomized in two prospective, parallel comparative multicentre trials to receive either conventional amphotericin B 1 mg/kg/d (c-AMB), liposomal amphotericin B 1 mg/kg/d(L-AMB1) or liposomal amphotericin B 3 mg/ kg/d (L-AMB3). Patients were entered if they had a pyrexia of unknown origin (PUO) defined as temperature of 38 degrees C or more, not responding to 96 h of systemic broad-spectrum antibiotic treatment, and neutropenia (< 0.5 x 10(9)/l).

Improvement of the chronic lymphocytic leukemia scoring system with the monoclonal antibody SN8 (CD79b).

A scoring system, based on the immunophenotypic analysis of a panel of five membrane markers (CD5, CD22, CD23, FMC7, SmIg) was shown to be useful in the distinction between chronic lymphocytic leukemia (CLL) and other B-cell lymphoproliferative diseases (non-CLL). We investigated whether the monoclonal antibody SN8 (CD79b) could improve our previous scoring system. Peripheral blood samples of 298 patients with CLL and 166 patients with non-CLL were analyzed by flow cytometry.

Rapid molecular cloning of rearrangements of the IGHJ locus using long-distance inverse polymerase chain reaction.

Clonal rearrangements of the Ig heavy chain (IGH) locus consisting of either intrachromosomal (VDJ) rearrangements or interchromosomal translocations are a consistent feature of all B-cell malignancies and may be used both diagnostically and to monitor response to therapy. Many of these rearrangements are targeted to the IGHJ segments, but only some can be amplified with regular polymerase chain reaction (PCR) techniques. To permit PCR amplification of potentially all IGHJ rearrangements, we have devised a method incorporating self-ligation of restriction endonuclease-digested DNA fragments with long-distance PCR (long-distance, inverse PCR [LDI-PCR]).

Growth of human T-cell lineage acute leukemia in severe combined immunodeficiency (SCID) mice and non-obese diabetic SCID mice.

Primary leukemic cells from patients with acute lymphoblastic leukemia (ALL) can be injected intravenously into mice with severe combined immunodeficiency (SCID) to create a model of human leukemia. Leukemic cells disseminate to murine tissues in a clinicopathologic pattern similar to that seen in humans. Thus far, reports of engraftment of lymphoid leukemia in SCID mice have mainly been from patients with B-cell lineage ALL, for which engraftment occurs more frequently with cells from high-risk patients.

Clustering of missense mutations in the ataxia-telangiectasia gene in a sporadic T-cell leukaemia.

Ataxia-telangiectasia (A-T) is a recessive multi-system disorder caused by mutations in the ATM gene at 11q22-q23 (ref. 3). The risk of cancer, especially lymphoid neoplasias, is substantially elevated in A-T patients and has long been associated with chromosomal instability.

G-CSF mobilization of haemopoietic cell populations in SCID mice engrafted with human leukaemia.

We have studied granulocyte colony-stimulating factor (G-CSF)-induced mobilization of haemopoietic cells in severe combined immune-deficient (SCID) mice engrafted with human leukaemia. Three leukaemia cell lines were investigated: the HL60 myeloblastic cell line, a chronic myeloid leukaemia (CML) xenograft cell line and an acute myeloid leukaemia (AML) xenograft line. Engraftment was detected using immunofluorescent staining of class I human leukocyte antigens and flow cytometry.

The significance of minimal residual disease in hairy cell leukaemia treated with deoxycoformycin: a long-term follow-up study.

We investigated the clinical significance and long-term follow-up of detecting minimal residual disease (MRD) in hairy cell leukaemia (HCL) in complete remission (CR) after treatment with deoxycoformycin (DCF). MRD was assessed in 23 patients by immunophenotyping peripheral blood and bone marrow frozen sections using a panel of antibodies, CD11c, CD25, CD103 and HC2, which detect hairy cells. 31 cases with active HCL were used as controls.

The human T-cell lymphotropic viruses types I/II are not involved in T prolymphocytic leukemia and large granular lymphocytic leukemia.

The possible involvement of the human T lymphotropic viruses type I and II (HTLV-I and -II) in lymphoproliferative disorders of mature T cells other than adult T cell leukemia/lymphoma (ATLL) has been controversial. Most studies have focused primarily on the cutaneous T cell lymphomas. However, skin involvement is a frequent feature of T prolymphocytic leukemia (T-PLL) and antibodies against HTLV-I and -II have been reported in individuals with large granular lymphocytic (LGL) leukemia.

HTLV-I and HTLV-II infections in hematologic disorder patients, cancer patients, and healthy individuals from Rio de Janeiro, Brazil.

To clarify the seroprevalence of human T-cell lymphotropic virus type I (HTLV-I) among hematologic and cancer patients in the State of Rio de Janeiro, Brazil, we investigated sera from 2430 individuals from the following groups: 152 patients with T-cell diseases, 250 with B-cell disorders, 67 with myeloid leukemia, 41 with Hodgkin's disease, 351 with a history of multiple blood transfusions, 235 patients with solid tumors of different types, and 109 family members of HTLV-I-infected patients. Antibodies to HTLV-I were screened by enzyme-linked immunosorbent assay or particle agglutination assays (or both). Repeatedly reactive samples were tested by Western blot and polymerase chain reaction assay to differentiate HTLV-I from HTLV-II.

Interferon-gamma+ and interleukin-2+ T cells in peripheral blood from multiple myeloma patients in relation to disease status and maintenance therapy with interferon-alpha2b (intron A).

Peripheral blood T cells from 83 patients with multiple myeloma (MM) were examined for the production of interferon-gamma (INF-gamma) and interleukin-2 (IL-2) using three-colour flow cytometry. Comparisons were made between the percentage of cytokine-positive lymphocytes in normal donors and in patients during remission or relapse. Patients were divided into those who were on maintenance therapy with interferon-alpha2b (intron A) and those who had no further treatment after high-dose melphalan (HDM) with or without autologous bone marrow (ABMR) or peripheral blood stem cell rescue (PBSCR).

Treatment of T-cell prolymphocytic leukemia with human CD52 antibody.

Purpose: T-prolymphocytic leukemia (T-PLL) is an aggressive malignancy of mature T cells refractory to conventional chemotherapy, with a median survival duration of 7.5 months. We report here promising results with the use of a genetically reshaped human CD52 antibody, CAMPATH-1H.

Sezary cell leukaemia: a distinct T cell disorder or a variant form of T prolymphocytic leukaemia?

We report the clinical, ultrastructural, immunophenotypic and virological features of nine cases of a rare type of mature T cell disorder formerly designated Sezary cell leukaemia. All patients presented with lymphocytosis ranging from 12.7 to 133 x 10(9)/l, bone marrow infiltration, splenomegaly and lymphadenopathy.

Antimicrobial prophylaxis to prevent opportunistic infections in patients with chronic lymphocytic leukemia after allogeneic blood or marrow transplantation.

Opportunistic infections have been a problem after BMT in CLL. We have allografted seven patients with B-CLL (n = 6) or B-prolymphocytic leukemia (n = 1) from matched siblings (n = 6) or a mismatched unrelated donor (n = 1). Amongst the first six, we saw two cases of recurrent or prolonged cytomegaloviremia and CMV disease, one listeria meningitis, and one fatal toxoplasma encephalitis.

In vivo 'purging' of residual disease in CLL with Campath-1H.

We assessed the role of human CD52 antibody (Campath-1H) in six patients with chronic lymphocytic leukaemia (CLL) treated to maximal response with purine analogues (fludarabine/deoxycoformycin) in whom persistent leukaemic infiltration of blood and bone marrow had precluded autologous stem cell transplantation. Five patients achieved haematological and histological complete remission following Campath-1H and one had minimal focal residual CLL in a trephine biopsy. Autologous transplantation was performed in two patients without complications and with rapid haemopoietic engraftment.

Two unbalanced translocations, t(12;22)(p13;q11) and t(12;?)(p13;?), in an aggressive chronic B-cell leukemia: TEL gene analysis using FISH.

The translocation t(12;22)(p13;q11) has been consistently described in myeloid malignancies and shown to result from a fusion between the TEL and MN1 genes. Previously described deletions of 12p in acute lymphoblastic leukemias have been recently shown to harbor undetected translocations involving the TEL gene at 12p13. We document a case of an aggressive chronic B-cell leukemia whose cells had trisomy 12 and two unbalanced translocations involving 12p13, including a t(12;22)(p13;q11) as shown by conventional cytogenetics and fluorescence in situ hybridization (FISH).

Phase II multicenter study of human CD52 antibody in previously treated chronic lymphocytic leukemia. European Study Group of CAMPATH-1H Treatment in Chronic Lymphocytic Leukemia.

Purpose: CAMPATH-1H is a human immunoglobulin G1 (IgG1) anti-CD52 monoclonal antibody (MAb) that binds to nearly all B- and T-cell lymphomas and leukemias. We report the results of a multicenter phase II trial that used CAMPATH-1H in previously chemotherapy-treated patients with chronic lymphocytic leukemia (CLL).

Materials And Methods: Twenty-nine patients who had relapsed after an initial response (n = 8) or were refractory (n = 21) to chemotherapy were treated with CAMPATH-1H administered as a 30-mg 2-hour intravenous (IV) infusion thrice weekly for a maximum period of 12 weeks.

p53 abnormalities in B-cell prolymphocytic leukemia.

B-cell prolymphocytic leukemia (B-PLL) is an aggressive disorder of mature B cells with distinct clinical and pathologic features. To determine the incidence of abnormalities of p53, we analyzed 19 cases of B-PLL by DNA blot to assess loss of heterozygosity (LOH) at 17p13.3, by immunocytochemistry to assess p53 expression, and by direct DNA sequencing of polymerase chain reaction-amplified exons 5 to 9 of the p53 gene.

Bilineal acute leukemia of B and T lineage with a novel translocation t(9;17)(p11;q11).

We describe a case of bilineal leukemia in a 5-year old boy with a rare immunophenotype and the novel translocation t(9;17)(p11;q11) as the sole chromosomal abnormality. Two immunologically distinct blast cell subsets expressed T-markers (CD2, CD5, CD7) and common ALL markers (TdT, CD19, CD22, CD10), respectively. Both cell populations were CD34 negative.

Interphase cytogenetics in chronic lymphocytic leukemia.

The incidence of trisomy 12 and 13q12-q14 abnormalities in patients with chronic lymphocytic leukemia (CLL) was determined by conventional cytogenetics and interphase fluorescence in situ hybridization (FISH). In the analysis of 580 consecutive patients, trisomy 12 was detected by conventional cytogenetics in 39 cases (9%) and 117 cases (20%) by FISH. Trisomy 12 was shown to be associated with advanced clinical stage, atypical morphology, and higher proliferative activity.

Relationship of T leukaemias with cerebriform nuclei to T-prolymphocytic leukaemia: a cytogenetic analysis with in situ hybridization.

Sezary cell leukaemia (SCL) is a mature T-cell leukaemia with characteristic cerebriform nuclei, whereas Sezary syndrome (SS) involves a mature T-cell lymphoma with a similar nuclear morphology. We have examined these diseases by cytogenetics chromosome painting and fluorescence in situ hybridization (FISH). Both diseases had complex cytogenetic abnormalities.