Demonstration of functional CD40 in B-lineage acute lymphoblastic leukemia cells in response to T-cell CD40 ligand

Because activated T cells were previously shown to induce proliferation of human normal B-cell precursors (BCP) via the CD40 pathway, we investigated the effects of T cells on leukemic blasts isolated from patients with B-lineage acute lymphoblastic leukemia (BCP-ALL). An anti-CD3 activated human CD4+ T-cell clone was found to induce significant call proliferation in four of nine BCP-ALL samples analyzed. In one of these cases, the T-cell effect was clearly dependent on interaction between CD40 and its ligand. Accordingly, a more thorough analysis was performed on this particular leukemia (case 461, adult early pre-B-ALL, mBCR+, Philadelphia+, i(9q)+). Thus, autologous CD4+ T cells isolated from the patient were also able to induce CD40-dependent proliferation of the leukemic blasts. Analysis of the phenotype after coculture showed that, among the CD19+ cells, a proportion gradually lost expression of CD10 and CD34, whereas some cells acquired CD23. In addition, and in contrast with normal BCP, activated T cells promoted maturation of a subset of the case 461 leukemic cells into surface IgM+ cells. The leukemic origin of the cycling and the maturing cells was assessed by the presence of i(9q), a chromosomal abnormality associated with this leukemia and evidenced by fluorescence in situ hybridization. Taken together, these results show that leukemic BCP can be activated via CD40 but that not all cases display detectable stimulation in response to T cells despite their expression of CD40. In addition, the present data suggest that CD4+ T cells could potentially play a role in the physiology of BCP-ALL.     

Essential thrombocythemia in transformation to smouldering megakaryoblastic leukemia with myelofibrosis

Leukemic transformation in essential thrombocythemia (ET) is rare. We describe a patient with ET which transformed to megakaryoblastic leukemia with myelofibrosis after treatment with melphalan for 8 years. His course after transformation smouldered for 20 months without antileukemic chemotherapy. A 61-year-old man was referred by a local doctor to Niigata University Hospital due to nasal bleeding in June 1984. Complete blood count (CBC) was as follows; hemoglobin 12.4 g/dl, platelets 268.8 x 10(4)/microliters, and white blood cells 11,900/microliters, with differentials of 39% PMN, 1% basophils, 2% eosinophils, 4% monocytes, and 13% lymphocytes. Bone marrow examination revealed hyperplasia of megakaryocytes without increase of reticulin fibers. Neutrophil alkaline phosphatase activity and karyotype of marrow cells were normal. ET was diagnosed. He was followed up by local doctor. The platelet count was controlled at a level of approximately 40 x 10(4)/microliters with melphalan for eight years. In January 1992 he developed pain in his lower extremities. He was admitted to our hospital on May 29, 1992. CBC was as follows; hemoglobin 8.9 g/dl, platelets 14.3 x 10(4)/microliters, and white blood cells 3,500/microliters, with differentials of 25% PMN, 5% monocytes, 28% lymphocytes, and 24% blasts. Bone marrow aspiration was unsuccessful and bone marrow biopsy revealed increases in fibroblasts and collagen fibers. Circulating blasts were positive for CD4, CD7, CD25, CD13, CD33, CD34, and HLA-DR and partly positive for CD41 and CD36. In ultrastructural cytochemistry blasts were positive for platelet peroxidase but negative for myeloperoxidase. Cytogenetic study revealed 46, XY, +der (1) t(1:7) (p11;q11) in all of five metaphases. He was diagnosed with megakaryoblastic leukemia accompanied by myelofibrosis.(ABSTRACT TRUNCATED AT 250 WORDS)     

Establishment and characterization of a megakaryoblast cell line with amplification of MLL

A new cell line with megakaryoblastic features, designated UoC-M1, was established from the malignant cells of a 68-year-old patient with acute myeloid leukemia. The patient's leukemic cells reacted with alpha-naphthyl acetate esterase and acid phosphatase and expressed CD7, CD24, CD34, CD38, CD45, HLA-DR and CD61. Cytogenetic analysis of the patient's malignant cells (and of the UoC-M1 cells) showed a human, male hypodiploid karyotype with many chromosome rearrangements and marker chromosomes. Spectral karyotyping (SKY) analysis complemented the G-banded karyotyping and clarified several chromosomal translocations and identified the marker chromosomes. Fluorescence in situ hybridization (FISH) and SKY analysis demonstrated that one marker chromosome contained three segments of chromosome 9 interspersed with three segments of chromosome 11, as well as a portion of chromosome 19. FISH analysis with a probe for MLL revealed that the UoC-M1 cells contained four copies of the MLL gene. Southern blot analysis determined that the MLL gene had a germline profile while Northern and Western analyses showed that the MLL mRNAs and protein were of the appropriate sizes. This is the first report of amplification of the MLL gene which may be an additional mechanism of leukemogenesis or disease progression.     

Proteins and cells on PEG immobilized silicon surfaces

Functional adhesion of blood and marrow leukemic cells from 14 acute myeloid leukemia patients presenting with hyperleukocytosis was evaluated by performing cytoadhesion assays on purified (extracellular matrix proteins) and non-purified supports (MRC5 fibroblastic cell line). Results, in 30-min chromium release assay, show a mean +/- S.D. adhesion to fibronectin, collagen, and laminin respectively of 30 +/- 17%, 20 +/- 13%, 25 +/- 17% for blood leukemic cells and 18 +/- 11%, 11 +/- 10%, 11 +/- 8% for marrow leukemic cells. These differences between blood and marrow cells were statistically significant (respectively P = 0.005, P = 0.01 and P = 0.002), while no difference was noted regarding adhesion to non-purified supports. The higher adhesion of blood blast cells to purified supports was observed regardless of CD34 expression. No significant difference was observed in the expression of cell surface VLA-molecules (CD29, CD49b, CD49d, CD49e, CD49f) between blood and marrow blast cells. The addition of GM-CSF or G-CSF induced increased adhesion of marrow blasts and decreased adhesion of blood blasts leading to a loss of the difference between blood and marrow cells. In a 60-min chromium release assay, marrow blasts adhered even more than blood leukemic cells to fibronectin. In contrast, marrow blasts from 'aleukemic' acute myeloid leukemia patients did not show any modification regarding their adhesion to extracellular matrix proteins when co-cultured with growth factors.     

CD95 (APO-1/Fas) mutations in childhood T-lineage acute lymphoblastic leukemia

CD95 (APO-1/Fas)-mediated apoptosis is pivotal in normal lymphocyte homeostasis and mutations of CD95 cause a benign autoimmune lymphoproliferation syndrome (ALPS) in humans and mice. However, tumors only rarely develop in these patients, and no CD95 mutations have yet been directly implicated in tumorigenesis. We therefore examined 81 de novo childhood T-lineage acute lymphoblastic leukemias (T-ALL) including 54 steroid-poor responders, 10 relapsed T-ALL, and 10 leukemic T-cell lines, for the presence of CD95 mutations using single-strand confirmation polymorphism and sequence analysis. In leukemic blasts and normal T cells of one patient, a heterozygous mutation in exon 3 of CD95 causing a 68Pro --> 68Leu change associated with decreased CD95-mediated apoptosis was found. In leukemic blasts and normal T cells of a second patient, a homozygous mutation in the promoter of CD95 causing disruption of a consensus sequence for AP-2 binding without decreasing constitutive CD95 expression was detected. No large intragenic alterations of CD95 were found, no homozygous loss was detected in the cell lines, and no CD95 mutations were detected in the relapses. The data presented here show that CD95 mutations occur in some T-ALL and may be of biological importance.     

Genetic localization of Cd63, a member of the transmembrane 4 superfamily, reveals two distinct loci in the mouse genome

We describe a patient with Philadelphia chromosome (Ph1)-positive acute lymphoblastic leukaemia (ALL) who developed it 2.5 years after being diagnosed with myelodysplastic syndrome (MDS). The patient initially had refractory anaemia (RA), but progressed to refractory anaemia with excess blasts (RAEB) 2 years later, that terminated in ALL. An immunophenotypic analysis of the lymphoblasts revealed CD10 and CD19 positive cells. The karyotype was normal 46,XY in RA phase, 46,XY,20q-during the RAEB phase, and 46,XY,t(9;22)(q34;q11),20q-during the ALL phase. Furthermore, p190 BCR-ABL mRNA was detected in the ALL blasts. These findings indicate that this ALL arose from the MDS clone through multiple cytogenetic evolutions, the final event of which was the acquisition of p190 BCR-ABL type Ph1.     

Simultaneous progressive multifocal leukoencephalopathy, Epstein-Barr virus (EBV) latent infection and cerebral parenchymal infiltration during chronic lymphocytic leukemia

We report a non-HIV patient who had B chronic lymphocytic leukemia (CLL) with progressive multifocal leukoencephalopathy (PML) and diffuse cerebral leukemic parenchymal infiltration in the presence of JC virus and Epstein-Barr virus (EBV) cerebral co-infection. Multiple subcortical hypodensities lining the cortico-subcortical junction were present within the white matter on computerized tomography (CT) scan, with large areas of high signal intensity on T2-weighted sequences on magnetic resonance imaging (MRI). JCV DNA was identified in peripheral blood nuclear cells and cerebrospinal fluid polymerase chain reaction (PCR) DNA/DNA hybridization plus Southern blot analysis. Frontal stereotactic biopsy confirmed the diagnosis of PML by immunocytochemistry, in situ hybridization (ISH) with JC Enzo probe and electron microscopy. Leukemic B cells with the same phenotype as leukemic blood cells were disseminated in the demyelinated areas. They were labeled by anti-latent membrane protein and by BamHl W EBV probe after ISH. Adhesion and activation molecules were positive for CD23. Autopsy showed diffuse visceral leukemic infiltration without acutization. EBV-transformed B lymphocytes would favour JCV penetration and/or intracerebral reactivation of previously latent JCV infection with further development of simultaneous PML and cerebral CLL infiltration in an immunosuppressed patient.     

The IL-6 gene expression by leukemic cells from acute lymphoblastic leukemia common and T type and modulation of IL-6 production by TNF

The tumour necrosis factor alpha (TNF-alpha) and interleukin-6 (IL-6) mRNA accumulation and the release of the cytokines TNF-alpha and IL-6 was determined in leukemic cells isolated from bone marrow biopsy from patients with acute lymphoblastic leukemia: ALL-common type (cALL), 11 patients; ALL-T type, nine patients. The non-leukemic bone marrow cells (BMMC) and peripheral blood mononuclear cells (PBMC) from healthy donors were used as a control. The mRNA was assessed by fluorescent in situ hybridization in cell suspension and analyzed with flow cytometry. The accumulation of cytokine mRNA was higher in cALL cells as compared to ALL-T and PBMC (control) and was comparable to cytokines mRNA accumulation in BMMC. The production of IL-6 by leukemic cells from both types of leukemia was significantly lower than in BMMC. The bioactive TNF was not detected in either of the leukemia groups studied. TNF-alpha protein was produced by ALL-T cells and BMMC but not by cALL type of leukemic cells. The synthesis of IL-6 was significantly enhanced by TNF-alpha in BMMC and ALL-T while the presence of TNF-alpha had no effect on IL-6 synthesis in the culture of cALL leukemic cells. It was concluded that despite IL-6 and TNF-alpha mRNA contents, leukemic cells representing early stage of B-cell development (CD10+) showed disregulation of production of these cytokines.     

Follow-up of residual disease using metaphase-FISH in patients with acute lymphoblastic leukemia in remission

Metaphase-FISH (fluorescence in situ hybridization) was used to detect cells with a chromosomal trisomy and/or translocation in 25 patients with acute lymphoblastic leukemia (ALL) in remission. Twelve patients were treated with chemotherapy alone and 13 patients received bone marrow transplantation after initial chemotherapy. Patients were followed up for 8-56 months (median 18 months). In this study, a total of 82 bone marrow samples were analyzed. Metaphase-FISH identified chromosome morphology, even banding, in cells from which FISH signals were studied. Thus, it is as reliable as standard karyotype analysis and does not cause false positive results. Furthermore, more than 1000 cells can be analyzed in 3-6 h which equals the time it takes to analyze 20 metaphases by standard karyotype. The time span before the first positive sample seems to be insignificant with regard to the outcome of relapse. All six patients, who had more than 1% of abnormal cells detected at any sampling or whose consecutive follow-up samples showed an increasing frequency (up to 1%) of abnormal cells, relapsed. Absence or occurrence of low numbers of abnormal cells at a frequency of 0.05-0.8% followed by their disappearance was in agreement with continuing complete clinical and hematologic remission (CR) in 16 (84%) of 19 patients. Our results indicate that metaphase-FISH is a reliable technique for quantifying residual leukemic cells. The technique is available in standard cytogenetic laboratories and can be applied to routine follow-up of ALL patients who have a suitable chromosomal aberration.     

CD45 gating of acute leukemia

Flow cytometry is a powerful tool for immunophenotyping of acute leukemia. Gating of leukemic cells is currently performed on the two dimensional display of forward scatter (FSC) and side scatter (SSC). However, this gating method can not discriminate leukemic cells from contaminated normal cells. Therefore, we used a CD45 monoclonal antibody to detect leukemic cells (CD45dlm cells) in combination with the SSC parameter. This CD45-SSC gating method was very useful for immunotyping of AML and ALL, especially leukemia with a low percentage of blasts. We recommend this new gating method for more accurate immunophenotyping of acute leukemia.     

Characterization of a novel human natural killer-cell line (NK-YS) established from natural killer cell lymphoma/leukemia associated with Epstein-Barr virus infection

A novel cell line was established from a patient with a leukemic-state nasal angiocentric natural killer (NK) cell lymphoma with systemic skin infiltration. The morphology of the leukemic cells was large-granular-lymphocyte (LGL), and their immunophenotype was CD2+, CD3-, CD5+, CD7+, CD16-, CD56+, and CD57-. The presence of Epstein-Barr viral (EBV) genome was shown in specimens from the patient's nose, skin, and peripheral blood by in situ hybridization using an EBV-encoded small RNA-1 probe or by Southern blotting using a terminal-repeat probe of the EBV genome. Leukemic cells were cocultured with a mouse stromal cell line (SPY3-2) in the presence of 100 U/mL recombinant human interleukin-2 and a novel stromal cell-independent cell line, NK-YS, was established. The NK-YS cells showed LGL morphology and expressed surface CD2, CD5, CD7, CD25, CD56, and CD95. The NK-YS cells retained cytotoxicity against K562 and Jurkat cells. A Southern blotting using a terminal-repeat probe of EBV showed that NK-YS and fresh leukemic cells had a clonal EBV genome, whereas the T-cell receptor beta and gamma chain genes of NK-YS were not rearranged. In an immunocytochemical analysis, the NK-YS cells showed a type-II latent infection of EBV. The NK-YS cells preserved the original characteristics of NK cell lymphoma/leukemia and will be a useful tool for the study of biological characteristics of EBV-associated nasal angiocentric NK cell lymphoma/leukemia.     

Hopwood, affirmative action, and deaf education

Leukemic cells of B-lineage acute lymphoblastic leukemia (ALL) are regarded as the malignant counterparts of immature, physiologic B cell precursors (BCPs). To determine whether phenotypic differences exist between these corresponding cell types, we investigated samples of normal pediatric bone marrow (n=30) as well as of B-precursor ALL at diagnosis (n=53; common and pre-B subtype). Using three-color multiparameter flow cytometric analysis, we compared the leukemic populations with the physiologic BCPs of corresponding maturity with respect to the intensity with which they expressed a series of antigens. In some of these antigens, leukemia-associated aberrations were frequently observed. In particular, overexpression of CD10 was displayed by 65% of ALL samples, whereas 58% of leukemic cases aberrantly exhibited very low or no CD45RA expression. Regarding CD11a and CD44, 47% and 35% of ALL populations were aberrant as defined by either the absence or significant overexpression of the antigen. In contrast, antigen densities of CD49d, CD49e, and CD99 on leukemic cells were in the normal range of values for BCPs. Combining the patterns of frequently aberrant markers in a comprehensive analysis, we were able to identify individual phenotypic leukemic cell aberrations in up to 98% of investigated cases. CD10 and/or CD45RA were aberrant in 86% of cases overall, emphasizing the high discriminative potential of these two markers. Using comparative phenotype mapping based on quantitatively aberrant, leukemia-associated antigenic patterns, we were able to detect leukemic blasts among normal bone marrow cells at frequencies as low as 10(-5). We speculate that our approach may have a profound impact on the development of new strategies for minimal residual disease investigations in patients with BCP-ALL.     

Differentiation of t(5;17) variant acute promyelocytic leukemic blasts by all-trans retinoic acid

All-trans retinoic acid (ATRA) induces differentiation of acute promyelocytic leukemic (APL) blasts from patients with t(15;17) APL. However, blasts from patients with the t(11;17) variant do not differentiate in response to ATRA. Our group has identified a variant of APL characterized by t(5;17) and expression of the NPM-RAR fusion gene product. From case reports it has been difficult to establish whether ATRA induces clinical responses in patients with this variant. In order to determine whether t(5;17) blasts differentiate with ATRA, we harvested mononuclear bone marrow cells from a patient with t(5;17) APL at time of relapse and cultured them in medium containing ATRA. Morphologic analysis of cytospins after 7 days of culture revealed that 60% of cells in the ATRA-treated culture had differentiated into mature neutrophilic forms, as opposed to less than 1% in the control culture. Seventy-three percent of cells acquired NBT positivity after exposure to ATRA, compared with 1% in the control culture. These results indicate that t(5;17) blasts retain the ability to terminally differentiate in response to retinoic acid.     

Postoperative stability after sagittal split ramus osteotomy with condylar-positioning appliance and screw fixation: asymmetric versus symmetric cases

BACKGROUND AND OBJECTIVE: Myelodysplastic syndrome progenitor cells can be grown and expanded in long term bone marrow liquid cultures in the presence of multiple cytokines. In this study we investigated the pattern of differentiation and response to growth factors in six cases of myelodysplastic syndrome (MDS) with well-defined cytogenetic abnormalities by means of conventional cytogenetics and fluorescence in situ hybridization (FISH). METHODS: Bone marrow cells were grown in stroma-free liquid cultures in the presence of SCF, IL-3, IL-6 and GM-CSF. RESULTS: IN three cases a CFU-GM expansion comparable to normal controls was observed, together with a decrease or increase of cells with abnormal karyotype. Two cases showed no response to growth factor stimulation, morphological signs of terminal myeloid differentiation and increase (one case) or decrease (one case) in the percentage of abnormal FISH signals along the cultures. In one additional case, while CFU-C expansion was present, clearcut leukemic transformation was observed in the culture, together with a sharp decrease in the percentage of abnormal FISH signals, indicating a leukemic transformation of MDS progenitor cells with a normal karyotype. INTERPRETATION AND CONCLUSIONS: Our data indicate that FISH analysis is generally a poor indicator of clonality in MDS; nevertheless, determining the kinetics of cytogenetically abnormal clones in liquid bone marrow cultures may provide insight as to the growth abnormalities of MDS progenitor cells and may be useful prior to in vivo growth factor administration.     

Vitamin K2 selectively induces apoptosis of blastic cells in myelodysplastic syndrome: flow cytometric detection of apoptotic cells using APO2.7 monoclonal antibody

We have previously reported that vitamin K2 (VK2) but not VK1 has a potent apoptosis-inducing effect on freshly isolated leukemia cells from patients with various types of leukemia. By multi-color flow cytometric analysis using monoclonal antibody (mAb), APO2.7, which detects mitochondrial 7A6 antigen specifically expressed by cells undergoing apoptosis, we further investigated the apoptosis-inducing effect of VK2 on minor populations of leukemic blast cells in bone marrow from patients with myelodysplastic syndrome (MDS) and overt myeloid leukemia (post-MDS AML). Limiting dilution of CD95 (anti-Fas) mAb-treated apoptotic Jurkat cells with nonapoptotic CTB-1 cells revealed that APO2.7-positive Jurkat cells were consistently detectable by flow cytometry when present at levels of at least 5% in the CTB-1 suspension. In patient samples the gating area for leukemic clone was determined using cell surface antigen-specific mAbs conjugated with either fluorescein isothionate (FITC) or phycoerythrin (PE) and subsequently the cells stained with phycoerythrin cyanine (PE-Cy5)-conjugated APO2.7 mAb were assessed within the gating area of the leukemic clone for monitoring apoptosis. Treatment of the bone marrow mononuclear cells with 3-10 microM of VK2 (menaquinone-3, -4 and -5) in vitro potently induced apoptosis of the leukemic blast cells as compared with the untreated control cells in all 15 MDS patients tested. This effect was more prominent on blastic cells than that on mature myeloid cells such as CD34-/CD33+ gated cells. In addition, VK2 performed much less effectively on CD3-positive lymphoid cells. In contrast to VK2, VK1 did not show apoptosis-inducing activity. These data suggest that VK2 may be used for treatment of patients with MDS in blastic transformation.     

Comparison of simultaneously obtained arterial and capillary blood gases in pediatric intensive care unit patients

In the present study the migration of human monocytes towards the supernatants of five different human myeloid leukemic cell lines, four different human lymphatic leukemic cell lines and blasts derived from three different patients with acute myeloid leukemia (AML) was studied and the role of monocyte chemoattractant protein (MCP)-1 was established with an ELISA assay. Large differences in migration of monocytes towards the leukemic cell supernatants were shown (variation of approximately 10 to 150% compared to positive control), but high amounts of monocyte migration was always restricted to myeloid leukemic cells (cell lines or patient blasts). MCP-1 turned out to play a major role in the migration, firstly since there was a direct correlation between the amount of migration and the concentration of MCP-1 in the supernatants, and secondly since the addition of anti-hMCP-1 was able to inhibit migration to background level in all cases. Cytotoxicity experiments with a MTT test using MCP-1-stimulated monocytes against two human myeloid leukemic cell lines showed no increase in cell death compared to unstimulated monocytes. It is concluded that monocyte migration towards leukemic cells is restricted to the myeloid lineage and is regulated by MCP-1, which is produced in different amounts by the leukemic cells. Besides, MCP-1 does not increase the direct toxic effects of monocytes on leukemic cells.     

POEMS syndrome: report on six patients with unusual clinical signs, elevated levels of cytokines, macrophage involvement and chromosomal aberrations of bone marrow plasma cells

POEMS syndrome is a multisystemic disorder characterized by the association of polyneuropathy, organomegaly, endocrinopathy, M protein, skin changes and various other systemic clinical signs. The pathophysiology of this syndrome remains largely unknown. In order to gain insight into its pathophysiology, we studied the clinical characteristics and performed serum analysis (auto-antibodies, cytokine levels) and phenotypic and cytogenetic studies of bone marrow plasma cells (BMPC) in six patients with unequivocal POEMS syndrome. Two unusual clinical signs were present in these patients: pulmonary hypertension (two patients) and diffuse cutaneous necrosis (one patient). No auto-antibodies against peripheral nerve (PN) antigens (SGPG and SGLPG glycolipids, GM1, GD1a, GD1b and GT1b gangliosides) were found. Sequential evaluations of serum cytokines (IL-1-beta, IL-6 and TNF-alpha) showed a moderate to marked elevations of IL-6 and TNF-alpha in all patients (up to six-fold for TNF-alpha and 16-fold for IL-6). Using in situ hybridization of these cytokines mRNAs on lymph node specimens of two patients who had an angiofollicular lymph node hyperplasia, a strong positivity was found with the IL-1-beta antisense probe in lymph node macrophages. On skin biopsy a high number of cells expressing TNF-alpha mRNA was observed in the dermis. The biological features of BMPC: phenotype (expression of CD19 and CD56 antigens), kinetics (Ki-67 index), karyotype, DNA content and chromosomal in situ hybridization remained those of BMPC found in monoclonal gammopathy of undetermined significance. We conclude that POEMS syndrome is a hypercytokinemic syndrome in which BMPC are not of malignant type. Macrophages are involved in this syndrome and their role has to be further investigated as well as treatments which act through an anti-cytokine mechanism.     

CD7, HLA-DR, CD38 positive acute undifferentiated leukemia with subcutaneous tumor and thymoma

A case of acute undifferentiated leukemia (AUL), accompanied by subcutaneous tumor and thymoma is reported. The analysis of immunophenotype showed that the leukemic blasts were positive for CD7, HLA-DR, CD38 and CD34 in 17.5% but negative results were obtained for other lymphoid and myeloid antigens. The leukemic blasts had a rearranged immunoglobulin heavy chain (IgH) gene and T cell receptor delta (TCR-delta) chain gene chromosomal abnormality, 47, XY, +8, t(13; 17) (q12; q21), -17, +M was observed. In general, the CR rate is low and prognosis is poor in patients with AUL. In our case, CR was not achieved by the therapy with JALSG-ALL87 protocol, but was achieved by subsequent treatment with high dose ara-C therapy and combination chemotherapy including intermediate-dose ara-C, mitoxantrone, etoposide and prednisolone.     

Leukemic phase of mantle cell lymphoma presenting as anemia: diagnosis by combining flow cytometry and cytomorphology

We report a case of mantle cell lymphoma in leukemic phase, which was diagnosed by a bone marrow biopsy performed as part of a workup for chronic anemia in a patient without lymphadenopathy. The patient, a 79-year-old man with diabetes mellitus, hypertension, chronic renal failure, congestive heart failure, and atherosclerosis, presented with claudication. On admission, he also had an 8-month history of anemia, during which time he experienced a 18-kg weight loss. On presentation, the patient had normal vital signs, anemia, leukocytosis (as well as an absolute lymphocytosis), and splenomegaly; as mentioned, lymphadenopathy was absent. A bone marrow biopsy showed an increase in small to intermediate-sized, slightly irregular lymphocytes in interstitial nodules. Flow cytometric immunophenotyping of the bone marrow identified a monoclonal population of cells, representing 25% of cells within the bone marrow, with expression of CD19, CD20, immunoglobulin M/D, lambda light chain, HLA-DR, and CD5; reactions for CD10 and CD23 were absent. Based on morphologic and immunophenotypic analysis of the bone marrow, as well as morphologic review of the peripheral blood smear, a diagnosis of mantle cell lymphoma involving the bone marrow and in leukemic phase was made. Subsequent polymerase chain reaction analysis of DNA from peripheral blood identified a population of cells with the bcl-1 rearrangement. This case is unique in that the diagnosis of mantle cell lymphoma was made without lymph node or spleen analysis and the patient, although exhibiting bone marrow and peripheral blood involvement by mantle cell lymphoma at presentation, did not have lymphadenopathy.