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Biomedical subjects

Y Morishima

Publications and source records attributed to Y Morishima.

At least 127 records · Page 7Linked to original sources
PubMed1998

A high dose chemoradiotherapy and peripheral blood stem cell support combined with the CD34(+)-selection method in cyclin D1(+)-mantle cell lymphoma.

Mantle cell lymphoma (MCL) is currently regarded as one of the most incurable lymphomas, although reliable prognostic indicators are not yet to be defined. In a previous report, it was indicated that most of the patients with immunohistochemically cyclin D1(+)-MCL pursued the lethal clinical course within 7 years, not having achieved complete remission (CR). Recently, a high dose chemoradiotherapy was carried out, this was supported by peripheral blood stem cell transplantation (PBSCT) using the CD34(+)-selection method in a 48-year-old female patient with cyclin D1(+)-MCL. The tumor cells were detected in her peripheral blood despite four courses of combination chemotherapy using CHOP regimen. Soon after the pre-conditioning of total body irradiation (TBI) and high dose melphalan, she received the PBSCT of 1.8 x 10(6)/kg CD34+ cells and showed rapid hematological recovery without life-threatening complications. The patient achieved CR and was alive, without disease, 730 days after PBSCT. Thus, CD34+ selected PBSCT appears to provide further insight into the effective treatment and possible cure of this aggressive disease, i.e. cyclin D1(+)-MCL.

Antigens, CD34↗
PubMed1998

Feasibility and pharmacokinetic study of a chimeric anti-CD20 monoclonal antibody (IDEC-C2B8, rituximab) in relapsed B-cell lymphoma. The IDEC-C2B8 Study Group.

BACKGROUND: In clinical trials in the USA, IDEC-C2B8 (a mouse-human chimeric anti-CD20 monoclonal antibody) has demonstrated high response rates with only mild toxic effects in relapsed B-cell lymphoma at a dose of four weekly 375 mg/m2 infusions. The aim of the present trial was to determine whether or not this dose is practically applicable to Japanese patients with relapsed B-cell lymphoma with respect to safety, pharmacokinetics and efficacy. PATIENTS AND METHODS: Patients with relapsed CD20+ B-cell lymphoma received intravenous infusions of IDEC-C2B8 once a week for four weeks. A total of 12 patients (four at 250 mg/m2 and eight at 375 mg/m2) were enrolled. RESULTS: All 11 eligible patients treated with either dose level tolerated IDEC-C2B8 well. Commonly observed adverse drug reactions were grades 1 or 2 non-hematologic toxicities during the infusion, consisting mostly of flu-like symptoms and skin reactions. All of the observed hematologic toxicities were of grade 3 or less, and transient. A rapid and sustained B-cell decrease in peripheral blood was observed, but no infectious episodes were encountered. Human anti-mouse and anti-chimeric antibodies were not detected. Of the 11 eligible patients (eight with follicular, two with diffuse large-cell and one with mantle cell lymphoma), two showed a complete response and five showed a partial response, and all of the seven responders had lymphoma with follicular histology. A pharmacokinetic analysis showed that the elimination half-life (T1/2) of IDEC-C2B8 was 445 +/- 361 hours, and that the serum antibody levels increased in parallel with the course of infusions, and in most patients was still measurable at three months. CONCLUSIONS: The dose of four weekly 375 mg/m2 infusions of IDEC-C2B8 is safe and effective in Japanese patients with relapsed B-cell lymphoma. Further studies evaluating IDEC-C2B8 are warranted.

Adult↗
PubMed1998

Establishment of an IL-2-dependent cell line derived from 'nasal-type' NK/T-cell lymphoma of CD2+, sCD3-, CD3epsilon+, CD56+ phenotype and associated with the Epstein-Barr virus.

A novel interleukin-2 (IL-2)-dependent cell line, HANK1, was established from a patient with CD56+ NK/T-cell lymphoma arising in the retroperitoneum. Morphologically, HANK1 is a pleomorphic large cell line with irregular nuclei, which contains azurophilic granules in the cytoplasm. Immunophenotypic analysis showed that HANK1 expressed CD2, CD3epsilon, CD56, TIA-1, granzyme B, and HLA-DR, but no other T-lineage markers. These features were the same as seen in the original tumour, and are highly characteristic of nasal and 'nasal-type' NK/T-cell lymphoma as described in the proposed W.H.O. classification. Genotypically, this cell line also demonstrated the germline configuration of the T-cell receptor beta, gamma and the immunoglobulin heavy chain genes and clonal integration of the Epstein-Barr virus (EBV) together with antigen expression with a type II latency pattern (LMP-1+ and EBNA2-). Furthermore, Southern blot analysis using the EBV termini as probes confirmed its derivation from the original lymphoma, and revealed that it contained multiple copies of the EBV genome. Dose-dependent growth on IL-2 was observed in an in vitro study with a doubling time of 3 d at maximal stimulation. These data indicate that HANK1 seemed to preserve the biological characteristics of the original tumour and therefore may serve as a good model for the further analysis of unusual 'nasal-type' NK/T-cell lymphoma.

Blotting, Southern↗
PubMed1998

Multiple polypoid lesions of primary mucosa-associated lymphoid-tissue lymphoma of colon.

AIMS: This study was focused on unusual cases of mucosa-associated lymphoid tissue (MALT) lymphoma presenting with multiple polypoid lesions of the colon and rectum with a special reference to the differential diagnosis of mantle cell lymphoma. METHODS AND RESULTS: The lesions of these five cases grossly showed a segmental distribution of nodular protrusions in three patients and of innumerable small polyps in two. These patterns of involvement simulated those of multiple lymphomatous polyposis, known as the gastrointestinal presentation of mantle cell lymphoma (MCL), and caused a differential diagnostic problem between MALT lymphoma and MCL, which have different prognostic and therapeutic implications. Their histological features are almost indistinguishable from each other, especially in the small biopsy specimens via endoscope. The most important procedure for their differentiation is cyclin D1 immunohistochemistry and its negative reaction provides strong indication of MALT lymphoma. Of interest, one case showed a rare karyotypic abnormality of t(11;18)(q21;q21), which has been reported specifically in MALT lymphoma. CONCLUSIONS: This study has indicated that the multiple polypoid lesions of the colon occur not only in MCL, but also in MALT lymphoma, making differential diagnosis between the two entities necessary, and cyclin D1 immunohistochemistry is indispensable for distinguishing between them.

Adult↗
PubMed1998

Growth inhibition of CD20-positive B lymphoma cell lines by IDEC-C2B8 anti-CD20 monoclonal antibody.

Treatment with IDEC-C2B8 (C2B8), the chimeric anti-CD20 antibody, was shown in a phase I-II study to be very effective for the treatment of low-grade B-cell lymphoma, in contrast to the results of most previous immunotherapies with monoclonal antibodies. In a study designed to elucidate the reason for this efficacy, two cell lines derived from lymphomas with BCL2 gene rearrangement (SU-DHL-4 and SU-DHL-6) showed remarkable growth inhibition and cell-death, and two other cell lines derived from a diffuse lymphoma (RC-K8) and a mantle cell lymphoma (SP-49) showed moderate growth inhibition, but neither a CD20 weakly positive cell line (NALL-1) nor a negative cell line (MOLT-4) showed any growth inhibition. An examination of the intensity of cell-surface CD20 expression showed no correlation between intensity and degree of growth inhibition among the four cell lines showing growth inhibition. Morphological examination revealed condensed and fragmented nuclei and budding of the plasma membrane, both characteristic of apoptosis, with some cells in these cell lines showing growth inhibition by C2B8. Such apoptosis was also confirmed by flow cytometric analysis, suggesting that, at least in part, apoptosis plays a role in this growth inhibition. This growth-inhibitory mechanism may thus account for the effectiveness of C2B8 antibody therapy.

Animals↗
PubMed1998

[Efficacy of granisetron, a 5-HT3 antagonist, in the prevention of nausea and vomiting induced by conditioning for hematopoietic stem cell transplantation].

One hundred and eleven patients receiving conditioning regimens for hematopoietic stem cell transplantation (HSCT) were administered a single intravenous dose (40 micrograms/kg) of granisetron before chemo-radio therapy. The efficacy of the drug was assessed every 24 hours, rating the control of nausea and vomiting as complete, major, minor or failure. On day 1, 23 of 48 patients (47.9%) who received cyclophosphamide (60 mg/kg/day), achieved control of emesis with complete or major response. On day 2, 17 of 47 patients (36.2%) achieved control emesis. During total body irradiation (TBI) (10 approximately 12 Gy/2 approximately 3 days), 21 of 33 patients (63.6%) achieved control of emesis on day 1 and 22 of 32 patients (68.6%) achieved control of emesis on day 2. During melphalan administration (60 approximately 100 mg/m2/day), 20 of 28 patients (71.4%) achieved control of emesis on day 1. Adverse effects were observed in seven patients but were not serious. We concluded that granisetron has a major role in preparation for HSCT.

Adolescent↗
PubMed1998

[N-3 polyunsaturated fatty acids in surgical nutrition].

Recent surgical nutrition includes the management of mediator to induce the stress response and immune function. N-3 polyunsaturated fatty acid (n-3 PUFA) were reported to increase the survival rate, and to improve the nutritional and immune status of septic or burned animals. N-3 PUFA also inhibited the proliferation and metastasis of cancer, and improved the cancer cachexia. N-3 PUFA decreased the production of cytokine and eicosanoid originated from n-6 PUFA, and reduced the inflammatory and stress response. Cell-mediated immunity was suppressed with the reduction of cytokine. But in the stressed state, N-3 PUFA ameliorated the stress induced immunosuppression. Alteration of transcription of cytokine mRNA, changes of membrane fluidity, and reduced expression of adhesion molecule were proposed to interpret these effects. In conclusion, n-3 PUFA can be applied for the surgical patients, especially for the critically ill patients.

Animals↗
PubMed1998

[Outcomes of 50 leukemia patients who received bone marrow transplants from unrelated donors].

Fifty leukemia patients were given bone marrow transplants (BMTs) from unrelated donors at Meitetsu Hospital. We studied the outcomes of their transplants from two perspectives: leukemia disease stage and acute graft versus host disease (GVHD). The probability of disease-free survival for standard-risk, high-risk, and super-high risk patients was 65%, 29%, and 8%, respectively. The main causes of death were septicemia, cardiac and renal failure, and relapse of leukemia in the high- and super-high risk patients, and grade III-IV acute GVHD in the standard-risk patients. The incidence of grade II-IV and grade III-IV acute GVHD was 32% and 17%, respectively. All 7 patients in whom grade III-IV severe acute GVHD developed died. We conclude that better control of acute GVHD and treatment of early stage complications are clearly important to improving the outcome of BMTs from unrelated donors, especially for high and super-high risk patients.

Acute Disease↗
PubMed1998

[Autologous peripheral blood stem cell transplantation for malignant lymphoma].

Autologous peripheral blood stem cell transplantation (PBSCT) for patients with malignant lymphoma has been extensively performed in Japan for several years. Some of the disease states of lymphoma are considered to be a good candidate for auto-PBSCT application. Sensitive relapsers in non Hodgkin's lymphoma should be treated with a combination of salvage therapy and high dose chemo(radio)-therapy with stem cell support, and up-front PBSCT is recommended for poor risk aggressive lymphoma. The clinical results and indications for auto-PBSCT including other types of lymphoma such as lymphoblastic lymphoma, mantle cell lymphoma, low-grade lymphoma and Hodgkin's disease will be reviewed in this paper.

Granulocyte Colony-Stimulating Factor↗
PubMed1997

DY-9760e, a novel calmodulin antagonist with cytoprotective action.

We report the pharmacological characterization and cytoprotective effect of DY-9760e, 3-[2-[4-(3-chloro-2-methylphenyl)-1-piperazinyl]ethyl]-5,6-dimethoxy-1-( 4-imidazolylmethyl)-1H-indazole dihydrochloride 3.5 hydrate, a novel antagonist of calmodulin. DY-9760e inhibited calmodulin-dependent enzymes, including calmodulin-dependent protein kinase II and IV, calcineurin, [corrected] calmodulin-dependent phosphodiesterase and myosin light chain kinase with Ki values of 1.4, 12, 2.0, 3.8 and 133 microM, respectively. These antagonistic effects of DY-9760e were more potent than those of W-7, N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide, another calmodulin antagonist. This compound showed little or no effect on calmodulin-independent enzymes, such as protein kinase A and C and calpain I and II. Analysis of the hydrophobic interaction of DY-9760e with calmodulin by using 2-p-toluidinylnaphthalene-6-sulfonate and 9-anthroylcholine revealed that, like W-7, DY-9760e bound to the hydrophobic regions of calmodulin. The [14C]DY-9760e binding assay indicated that DY-9760e bound to calmodulin at one class of binding site. Finally, DY-9760e substantially protected N1E-115 neuroblastoma cells from cytotoxicity induced by the Ca2+ ionophore, A23187. These results indicate that DY-9760e, a novel calmodulin antagonist, possesses a cytoprotective action and suggest that calmodulin plays a critical role in mediating some of the biochemical events leading to cell death following Ca2+ overload.

Calcimycin↗
PubMed1997

CD7+ and CD56+ myeloid/natural killer cell precursor acute leukemia: a distinct hematolymphoid disease entity.

The disease spectrum of natural killer (NK) cell leukemias and lymphomas has recently been expanding with the continuing evolution in diagnostic concepts. We describe here seven cases of acute leukemia of conceivable myeloid and NK cell precursor phenotype in six men and one woman varying from 19 to 59 years of age (median, 46 years). Striking extramedullary involvement was evident at initial presentation, with peripheral lymphadenopathy and/or mediastinal masses. Two lacked any leukemic cells in the bone marrow at diagnosis. Using cytochemical myeloperoxidase staining, less than 3% of the leukemic cells showed positive reactivity. However, expression of CD7, CD33, CD34, CD56, and frequently HLA-DR, but not other NK, T-cell, and B-cell markers was observed. Cytoplasmic CD3 was detected in three of the cases by flow cytometry and in six by Northern blotting, suggesting an origin from common progenitors between the NK cell and myeloid lineages. All but one presented germline configurations of the T-cell receptor beta and gamma chain genes and Ig heavy chain gene. With regard to morphology, the cells were generally L2-shaped, with variation in cell size, round to moderately irregular nuclei and prominent nucleoli, pale cytoplasm, and a lack of azurophilic granules. Histopathologic examination of biopsied specimens of extramedullary tumors showed a lymphoblast-like morphology, implying the differential diagnostic problem from lymphoblastic lymphomas, especially in cases lacking bone marrow involvement. Three patients were successfully treated with chemotherapy for acute myeloid leukemia (AML), whereas three other patients proved refractory to chemotherapeutic regimens for lymphoid malignancies, although two responded to subsequent AML chemotherapy. However, despite intensive chemotherapy, including allogeneic bone marrow transplantation, most persued fatal courses within 41 months. These data suggested that the CD7+ and CD56+ myeloid/NK cell precursor acute leukemia might constitute a distinct biologic and clinical disease entity. Its recognition appears to be particularly important for the clinicopathologic evaluation of CD56+ hematolymphoid malignancies and the development of therapeutic approaches to such disease.

Acute Disease↗
PubMed1997

Phase I/II trial of cure-oriented high-dose chemoradiotherapy with transplantation of CD34+ peripheral blood stem cells purified by the immunomagnetic bead method for refractory hematological malignancies. Nagoya CD34+ PBSCT Study Group.

A multicenter phase I/II clinical trial was conducted to evaluate the safety of a device (Isolex System; Baxter Health Corporation, Irvine, Calif., USA) using the immunomagnetic bead method to purify CD34+ stem cells from peripheral blood and to assess the efficacy and toxicity of high-dose chemoradiotherapy with peripheral blood stem-cell transplantation (PBSCT) using purified CD34+ stem cells in patients with refractory hematological malignancies. Patients eligible for the study included those who had T-cell acute lymphoblastic leukemia (T-ALL), lymphoblastic lymphoma (LBL), mantle-cell lymphoma (MCL), high-risk aggressive non-Hodgkin's lymphoma (NHL), and adult T-cell leukemia/lymphoma (ATLL) in first complete remission (CR) and those who had standard-risk aggressive NHL, indolent lymphoma, Hodgkin's disease, or acute promyelocytic leukemia (APL) in second CR or first partial remission (PR) after the completion of first-line chemotherapy and were chemosensitive to salvage chemotherapy, in whom tumor contamination of harvested peripheral blood stem cells (PBSCs) was possible due to bone marrow or peripheral blood involvement. Lack of CD34 expression by tumor cells was an important selection factor. Eight patients with hematological malignancies (six NHL patients, one ATLL patients, and one APL patient) were enrolled; their median age was 41 years (range 26-49 years). After consolidation and mobilization chemotherapy, two or three courses of apheresis were performed in each patient. After high-dose chemo(radio)therapy, in each patient a median of 1.8 x 10(6) cells/kg (range 8.2 x 10(5)-5.1 x 10(6) cells/kg) purified CD34+ PBSCs were infused; granulocyte colony-stimulating factor was given from day 1. Median times to hematopoietic recovery were as follows: WBC of > or = 1,000/microliter, day 11; platelet count of > or = 50,000/microliter, day 19; and reticulocyte count of > or = 10/1000, day 15. Two NHL patients relapsed at 23 and 9 months after PBSCT, respectively; the remaining six patients are alive and in CR. No severe toxicity was observed in any patient. Tumor contamination as measured using a polymerase chain reaction-mediated RNase protection assay at the 10-4 level was detected in the CD34(+)-purified fractions of 2 of the 5 samples analyzed; however, a reduction in contaminating lymphoma cells from the autograft of at least 1,000 to 10,000 orders of magnitude was achieved by CD34+ selection using the immunomagnetic bead method. High-dose chemoradiotherapy with transplantation of CD34+ PBSCs purified by the immunomagnetic bead method was thus shown to be an active and safe therapy for refractory hematological malignancies with bone marrow or peripheral blood involvement. However, it is too early for evaluation of the long-term survival benefit.

Adolescent↗
PubMed1997

Effects of insulin-like growth factor-1 on endotoxin translocation in burned rats receiving total parenteral nutrition.

The purpose of this study was to investigate the effect of insulin-like growth factor-1 (IGF-1) on the translocation of endotoxin from the gut of burned rats. Twenty-eight male Sprague-Dawley rats (7-wk-old) were subjected to 20% full-thickness scald burns and were divided into two groups. One group received 4 mg.kg-1.d-1 of IGF-1 (IGF-1 group, n = 14), and the other received saline (control group, n = 13). All rats were fed exclusively by total parenteral nutrition (TPN). On the second postburn day, rats were killed. The amount of endotoxin in the liver and spleen were measured. RNA from the terminal ileum was extracted, and Northern blot analyses of alpha-tubulin, beta-actin, cell division cycle-2 (cdc2), and immunoglobulin-A (IgA) were performed. Nitrogen balance was improved (p < 0.001), and the wet weight of intestine and its mucosa were increased significantly in the burned rats that received IGF-1. Gene expression of alpha-tubulin and beta-actin were not changed. Cdc2 was elevated (P < 0.05), but IgA was decreased (P < 0.05) in the IGF-1 group. Levels of endotoxin in the liver and spleen were significantly reduced (P<0.05) by the administration of IGF-1. A negative correlation between the levels of endotoxin in the liver and the weight of the intestinal mucosa was observed. In conclusion, IGF-1 improved nitrogen balance, promoted the proliferation of intestinal mucosa and reduced the translocation of endotoxin.

Actins↗
PubMed1997

Catabolism of lipoprotein-X induced by infusion of 10% fat emulsion.

The clinical significance of lipoprotein-X (Lp-X) induced by intravenous infusion of 10% fat emulsion was assessed, with special reference to atherogenesis, by in vitro experiment using purified Lp-X from the sera of patients receiving Intralipid 10%. Lp-X appeared after long-term intravenous infusion of 10% fat emulsion in the patients with intestinal fistula due to the anastomotic leakage. To clarify the role of Lp-X in terms of atherogenicity, the cholesterol metabolism of Lp-X in macrophages as scavenger cells and in hepatocytes as parenchymal cells was studied. When [3H]cholesterol-labeled Lp-X or oxidized low-density lipoprotein (o-LDL) was incubated with J-774 macrophages, the incorporation of Lp-X into macrophages was negligible compared with o-LDL. When Lp-X or high-density lipoprotein (HDL) was incubated with J-774 macrophages laden with [3H]cholesterol, the release of cholesterol from macrophages was enhanced by Lp-X as well as HDL. When [3H]cholesterol-labeled Lp-X LDL or HDL was incubated with the human hepatoma cell line of Hep G2 cells, the incorporation of Lp-X into Hep G2 cells was less than that of LDL, but similar to that of HDL. From these findings, it is suggested that the catabolism of Lp-X cholesterol generated with intravenous 10% fat emulsion was mediated by hepatocytes rather than by macrophages, indicating that the hyperlipidemia due to increased Lp-X may not be atherogenic.

Animals↗
PubMed1997

Complete cytogenetic response with host-derived hematopoiesis induced by cyclosporin A discontinuation in a patient with relapsed chronic myelogenous leukemia after bone marrow transplantation.

A 46-year-old woman with Ph-positive CML received an unmanipulated BMT from an HLA-identical brother, conditioned with busulfan-cyclophosphamide. Five months after BMT, cytogenetic relapse occurred, and CsA was decreased and then discontinued. Mild acute GVHD occurred, but gradually improved with no immunosuppression. Forty days after CsA discontinuation, both cytogenetic and fluorescence in situ hybridization analyses showed a host-derived normal karyotype, 46,XX, and no evidence of leukemic cells or donor graft. The sustained host-derived hematopoiesis lasted for 2 years until sudden recurrence of CML. In this case, the discontinuation of CsA led to GVHD and also suppression of the relapsed leukemia, presumably by a 'specific' GVL effect. There was also graft failure. The observation that subsequent hematologic recovery was of host origin implies that, at least in this case, the GVL effect was not directed against normal host-type hematopoiesis.

Bone Marrow Transplantation↗
PubMed1997

Activation of the human transglutaminase 1 promoter in transgenic mice: terminal differentiation-specific expression of the TGM1-lacZ transgene in keratinized stratified squamous epithelia.

Transglutaminase 1 (TGase 1) is a tissue-specific enzyme which is expressed in the keratinized stratified squamous epithelia and which catalyzes straightepsilon-(gamma-glutamyl) lysine cross-links of proteins to form the cell envelope at the periphery of cornified cells. A transient expression assay using a luciferase reporter gene linked to the 2.5 kb 5' upstream region of the human TGase 1 gene (TGM1) showed phorbol ester-responsive promoter activity in cultured normal human keratinocytes. To assess its promoter activity in vivo, we generated transgenic mice expressing the Escherichia coli beta-galactosidase gene (lacZ) directed by the 5' upstream region. beta-Galactosidase histochemistry revealed that the TGM1-lacZ transgene was expressed in terminally differentiating keratinocytes in upper layers of stratified squamous epithelia in embryonic, neonatal and adult transgenic mice. The expression pattern was similar to that of endogenous TGase 1 mRNA detected by in situ hybridization. Furthermore, topical application of a phorbol ester to adult tail skin enhanced expression of the transgene as well as TGase 1 mRNA in the epidermis. Thus, the 2.5 kb 5' upstream sequence of TGM1 includes elements regulating tissue- and terminal differentiation-specific gene expression in stratified squamous epithelia.

Animals↗
PubMed1997

Anaplastic large cell lymphoma: a distinct molecular pathologic entity: a reappraisal with special reference to p80(NPM/ALK) expression.

The p80(NPM/ALK) expression activated by the t(2;5) (p23;q35) translocation recently has been shown to play an important role in the pathogenesis of anaplastic large cell lymphoma (ALCL). However, the clinicopathologic significance of identification of p80 among ALCL cases has not been completely resolved. Difficulties also exist in the histologic and immunophenotypic identification of ALCL and Hodgkin's disease (HD) as separate processes, often complicating the clinicopathologic evaluation of and therapeutic approach to these entities. In order to clarify these issues, 67 specimens of ALCL and 63 specimens of HD (31 of the nodular-sclerosing type [NS-HD] and 32 of the mixed-cellularity type [MC-HD]) were immunostained using anti-p80 antibody and other relevant markers on paraffin sections. The clinicopathologic and immunophenotypic features were reviewed on the basis of p80 reactivity. The expression of p80 was detected in 43 of 67 cases of ALCL (64%), but none of HD. The p80+ ALCL cases constituted a very homogeneous group of tumors, characterized by the occurrence in a much younger group and relatively more favorable clinical course than the p80- ALCL, which were in keeping with the data previously reported. They showed virtually the identical immunophenotypic findings of p80+, CD30+, EMA+, CD15-, bcl-2-, and Epstein-Barr virus (EBV) with T- and null-cell phenotype, and showed the distinct morphologic features, including three cases of lymphohistiocytic/small-cell variant, as follows: the indented nuclei, often termed as reniform, embryolike, and horseshoelike; multiple, irregular, but indistinct nucleoli; and few reactive cells of eosinophils and epithelioid cells. Conversely, the 24 p80- ALCL cases, in which epithelial membrane antigen (EMA) and bcl-2 positivities were 33% and 55%, respectively, were heterogeneous and could be subdivided into five different categories, namely (a) 11 cases of HD-like ALCLs, (b) six cases of p80 common ALCL, (c) three cases of secondary ALCL, (d) two cases of primary cutaneous ALCL, and (e) two cases of primary classical ALCL that lacked p80 expression. This study clearly demonstrated that the immunohistochemical detection of p80 is of a crucial importance in delineating the biologically distinct entity of "primary classical ALCL" from various diseases that show morphologic and immunohistologic overlap, including HD and HD-like ALCL.

Adolescent↗