112例淋巴系统恶性肿瘤骨髓免疫表型分析

背景与目的:淋巴细胞白血病和淋巴瘤骨髓侵犯的诊断以细胞形态学为基础,而免疫分型可通过获得肿瘤细胞分化和发育阶段的信息使淋巴系统恶性肿瘤的诊断更为准确,为临床合理治疗和预后判断提供重要的科学依据.本研究应用多参数流式细胞术(flow cytometry,FCM)探讨淋巴细胞白血病和非霍奇金淋巴瘤(non-Hodgkin's lymphoma,NHL)骨髓侵犯的免疫表型特点.方法:收集112例病理确诊NHL并伴骨髓侵犯和淋巴细胞白血病患者的骨髓标本.应用FCM检测肿瘤细胞的免疫表型.结果:45例前驱B淋巴母细胞白血病/淋巴瘤(precursor B lymphoblastic lymphoma/leukemia,B-ALL/LBL)主要表达CD19、CD10、TdT、CD34、HLA-DR和CD20;32例前驱T淋巴母细胞白血病/淋巴瘤(precursor T lymphoblastic lymphoma/leukemia,T-ALL/LBL)主要表达胞内CD3(cytoplasmic CD3,CyCD3)、CD7、CD5、TdT、膜表面CD3(surface CD3,sCD3)和HLA-DR.77例前驱淋巴细胞肿瘤中,28例(36%)有髓系抗原CD13、CD33的表达;9例(20%)B-ALL/LBL病例有CD20与CD34共同表达,28例(87.5%)T-ALL/LBL病例有CyCD3与TdT共同表达.成熟淋巴细胞肿瘤35例,其中17例慢性淋巴细胞白血病/小淋巴细胞淋巴瘤主要表达CD19、CD20、CD5和HLA-DR,并有CD19与CD5共同表达.4例弥漫大B细胞性淋巴瘤主要表达CD19、CD20、CD10和HLA-DR.3例伯基特淋巴瘤主要表达CD19、CD10、CD20、SIgM.1例套细胞淋巴瘤表达CD5、CD19、CD20、HLA-DR.5例外周T细胞淋巴瘤(PTCL)主要表达sCD3、CD5、CD7、CD4或CD8.1例间变性大细胞淋巴瘤主要表达sCD3、HLA-DR.4例NK/T细胞肿瘤表达CD56、HLA-DR,也表达CD7或CD4或CD8.成熟淋巴细胞肿瘤不表达早期抗原如CD34、TdT.成熟淋巴细胞肿瘤可伴有髓系抗原CD13、CD33的表达.结论:淋巴系统恶性肿瘤侵犯骨髓采用形态学结合FCM免疫学分型可获得T、B细胞来源、肿瘤细胞分化阶段和异常抗原表达等参数,有助于临床诊断和微小残留病灶的检测.     

Immunologic markers in non-Hodgkin's lymphoma

The majority of non-Hodgkin's lymphomas (NHLs) are of B-cell lineage, with less than 20% of cases being of T-cell lineage. The B-cell NHLs phenotypically correspond to normal cells in the mid stages of normal differentiation. More specifically, by their expression of B-cell activation antigens, these tumors are the neoplastic counterparts of normal activated B cells. The follicular lymphomas--including the small cleaved, mixed small and large cell, and large cell types, as well as the small noncleaved cell (Burkitt's) lymphomas--represent malignant expansions of normal germinal center B cells by their expression of pan-B cell antigens, B-cell activation antigens, and CD10 (CALLA). The diffuse lymphomas also correspond to normal activated B cells. The small lymphocytic lymphomas express the low-affinity IL-2 receptor and CD5, both of which are induced on normal B cells following mitogen stimulation. The other diffuse B-cell NHLs similarly express activation antigens and resemble "transformed" B cells. The T-cell NHLs generally correspond to normal activated CD4+ T cells. These tumors--which include most peripheral T-cell lymphomas, cutaneous T-cell lymphomas, and HTLV-I-associated adult T-cell leukemias/lymphomas--express antigens induced on activated T cells, including IL-2 and transferrin receptors (CD25 and CD71, respectively), as well as HLA-DR. The lymphoblastic lymphomas, which are generally of T-cell lineage, phenotypically correspond to stages of intrathymic differentiation, often by their coexpression of CD4 and CD8, as well as expression of CD1. It remains controversial whether the immunophenotype of lymphoblastic lymphoma differs significantly from T-cell acute lymphoblastic leukemia. Since immunologic heterogeneity of NHL was first observed, attempts have been made to employ the data as a prognostic variable. Early studies suggested that lineage derivation or expression of markers of proliferating cells affected outcome in NHL. However, these reports were often retrospective, included various histologies, and did not treat patients uniformly. More recent prospective studies with relatively uniformly treated patients, predominantly involving DLCL, suggest that certain immunologically defined subgroups may have significantly different clinical outcomes. However, additional clinical studies will be necessary before treatment options are based upon immunologic markers.     

Patients with Epstein Barr virus-positive lymphomas have decreased CD4(+) T-cell responses to the viral nuclear antigen 1

Epstein Barr virus (EBV) causes lymphomas in immune competent and, at increased frequencies, in immune compromised patients. In the presence of an intact immune system, EBV-associated lymphomas express in most cases only 3 or fewer EBV antigens at the protein level, always including the nuclear antigen 1 of EBV (EBNA1). EBNA1 is a prominent target for EBV-specific CD4(+) T cell and humoral immune responses in healthy EBV carriers. Here we demonstrate that patients with EBV-associated lymphomas, primarily Hodgkin's lymphoma, lack detectable EBNA1-specific CD4(+) T-cell responses and have slightly altered EBNA1-specific antibody titers at diagnosis. In contrast, the majority of EBV-negative lymphoma patients had detectable IFN-gamma expression and proliferation by CD4(+) T cells in response to EBNA1, and carry EBNA1-specific immunoglobulins at levels similar to healthy virus carriers. Other EBV antigens, which were not present in the tumors, were recognized in less EBV positive, than negative lymphoma patients, but detectable responses reached similar CD8(+) T cell frequencies in both cohorts. Patients with EBV-positive and -negative lymphomas did not differ in T-cell responses in influenza-specific CD4(+) T cell proliferation and in antibody titers against tetanus toxoid. These data suggest a selective loss of EBNA1-specific immune control in EBV-associated lymphoma patients, which should be targeted for immunotherapy of these malignancies.     

B-cell marker negative (CD7+, CD19-) Epstein-Barr virus-related pyothorax-associated lymphoma with rearrangement in the JH gene

Pyothorax-associated lymphoma (PAL) develops decades after receiving artificial pneumothorax for pulmonary tuberculosis. The lymphomas, develop in tissue affected by long-standing severe inflammatory process. Most cases demonstrate diffuse large B-cell lymphoma. We present a patient with T-cell phenotype-positive and B-cell phenotype-negative (CD7+, CD43+, CD19-, and CD20-) PAL. Southern blot hybridization using immunglobulin heavy chain J region (IgH) gene probe revealed a monoclonal rearrangement, and hybridization using T-cell receptor beta chain (TCR) gene probe revealed a germline configuration. This indicates that the tumor origin was of B-lymphocytes. Chromosomal abnormality of the lymphoma was complicated. It suggested that many transformations occurred. In the transformation process, probably B-cell antigens were lost, and T-cell antigens were aberrantly expressed.     

Immunophenotypic characterization of follicle-center-cell-derived non-Hodgkin's lymphomas

The distribution of the BLA, CALLA (CD 10), AC-2 (CD 39), MHM-6 (CD 23), LB-I, and 351C5 (CD 45R) antigens in 40 non-Hodgkin's lymphomas was demonstrated by immunohistochemical staining of frozen tissue sections. Nine out of 10 centroblastic and centrocytic follicular and diffuse type of lymphomas (CB/CC F/D) and all 10 cases of CB/CC follicular lymphomas were BLA+ and CALLA+. A few cases also showed weak expression of activation antigens (AC-2, MHM-6 and LB-I) and 351C5. In contrast, 3 CC and 3 lymphoblastic (non-Burkitt) lymphomas showed a heterogeneous pattern of distribution with dominating activation antigen expression. A single case of lymphoblastic lymphoma of Burkitt-like type expressed BLA and CALLA but not activation antigens. In reactive follicular center and FCC lymphomas different cell populations appeared to express BLA and activation antigens, respectively. Assessment of staining intensity and proportion of the stained cells indicated that almost all BLA+ cells are CALLA+. CALLA+ BLA- cells were regularly present, in addition. The co-expression of BLA and CALLA in the same cell was confirmed by double immuno-enzymatic staining. By the same technique, BLA+ and CALLA+ cells were shown to be activation-antigen negative.     

Phenotypic and genotypic heterogeneity of peripheral T-cell lymphoma

A series of 21 phenotypically characterised T-cell lymphomas histologically defined as lymphocytic, lymphoblastic, immunoblastic, AILD type, pleomorphic, T-zone and Lennert's T-cell lymphoma, were investigated for T-cell receptor (TcR) and immunoglobulin (Ig) gene rearrangements. Phenotypic analyses of frozen sections and cell suspensions were heterogeneous and in many cases no single T-cell marker recognised all of the malignant cells. Data derived by staining with antibodies reactive with antigens in paraffin embedded tissue were consistent with T NHL in all cases except lymphoblastic lymphoma. TcR gene rearrangements were observed in lymphocytic, lymphoblastic and immunoblastic lymphoma, however, in the remaining 14 phenotypically and histologically defined peripheral T-cell lymphomas, 2 showed rearrangement of TcR gamma and beta genes consistent with T NHL and 2 showed Ig JH rearrangements only, suggestive of either reactive T-cell populations masking cryptic disease or presence of tumour populations with aberrant gene rearrangement and expression of T lineage antigens. No Ig or TcR gene rearrangements were found in the remaining 10 cases, in which morphologically identifiable tumour cells comprised 10-90% of the cell population. In 3/6 cases tested some CD3 positive cells failed to stain with WT31 or beta F1, monoclonal antibodies that recognise determinants on combined TcR gamma beta or TcR beta chains respectively. Whether these cases represent tumours arising from an undetermined cell of origin or polyclonal expansions of T-cells remains to be determined. Our results confirm the phenotypic heterogeneity of histologically defined peripheral T-cell lymphoma and indicate that in these particular histological subtypes gene rearrangement analysis can also yield heterogeneous results which may be unhelpful in determining cell lineage and clonality.     

Cutaneous CD56 positive natural killer and cytotoxic T-cell lymphomas

We report two cases of CD56 positive natural killer (NK) cell and cytotoxic T-cell cutaneous lymphomas and review the literature on these rare forms of non-Hodgkin's lymphoma. The first case was diagnosed to have extra nodal NK/T-cell lymphoma, nasal-type. She had a rapid downhill clinical course and died within 3 months of presentation. She had been started on systemic chemotherapy but did not respond. The second case was diagnosed as subcutaneous panniculitis-like T-cell lymphoma, CD56 positive variant. She presented with skin nodules that were quiescent for 10 years. Then the course of the disease suddenly changed and progressed rapidly. She had systemic chemotherapy and initially had a complete response, but she relapsed within 1 month of completion of chemotherapy. She then had partial response with further chemotherapy but relapsed rapidly. She died within 15 months of her lymphoma changing to its aggressive form. These cases illustrate the often poor prognosis of cutaneous CD56 positive lymphomas.     

T-lymphoblastic and peripheral T-cell lymphomas in the northern part of The Netherlands. An immunologic study of 29 cases

The morphologic type, immunophenotypes, and clinical presentation of 12 cases of T-lymphoblastic lymphoma and 17 cases of peripheral T-cell lymphoma were studied. The lymphoblastic cases were subclassified according to intrathymic stages of T-cell differentiation. Two cases had an early intrathymic immunophenotype (CD4-negative, CD8-negative, CD1-negative), seven cases had an intermediate intrathymic immunophenotype (CD1-positive, CD4-positive, CD8-positive), and two cases had a late intrathymic immunophenotype (CD1-positive, CD8-positive, CD4-negative); one case expressed T-cell and B-cell markers. The peripheral T-cell lymphomas were morphologically subclassified according to the updated Kiel classification. T-cell lymphomas of low-grade malignancy--chronic lymphocytic lymphoma, T-zone lymphoma, and pleomorphic small cell lymphoma--in general had a complete immunophenotype matching the immunophenotypes of normal peripheral T-cells. In addition these cases were CD38-positive and HLA class II-positive. The T-cell lymphomas of high-grade intermediate and large cell, immunoblastic and large cell anaplastic lymphoma--were characterized by loss of T-cell markers. For their establishment as T-cell lymphoma a panel of monoclonal antibodies is needed.     

CORRELATION OF IMMUNOLOGICAL SURFACE ANTIGENS WITH SURVIVAL IN DIFFUSE LARGE CELL LYMPHOMA

The prognostic value of immunophenotyping lymphomas with a panel of monoclonal antibodies (Mab) to various lymphoid antigens was assessed by studying 47 cases of diffuse large cell lymphoma. Cell suspensions were analysed by flow cytometry after labelling by indirect immunofluorescence. Thirty-eight cases were demonstrated to be of B cell and nine of T cell phenotype. Univariate analysis demonstrated that survival was significantly longer in patients expressing higher levels of HLA-DR (p=0·01) and normal levels of CD8 (p=0·04) but was not significantly associated with any of the other antigens. Our results support the possible value of HLA-DR in determining the prognosis of patients with diffuse large cell lymphoma.     

Morphology, immunohistochemistry and genetics of peripheral T cell lymphomas

T-cell lymphomas are relatively rare in our material; they comprise less than 20% of all non-Hodgkin's lymphomas. A definitive classification of the T-cell lymphomas still does not exist. Nonetheless, it is now possible to distinguish thymic and prethymic, i.e. lymphoblastic lymphomas, from postthymic, i.e. peripheral T-cell lymphomas. Of the peripheral T-cell lymphomas the following are relatively well defined: chronic lymphocytic leukemia of T type (T-CLL) and prolymphocytic leukemia of T type (T-PLL), mycosis fungoides and Sézary's syndrome, lymphoepithelioid lymphoma (Lennert's lymphoma), T-zone lymphoma T-immunoblastic lymphoma, and large cell anaplastic lymphoma (so-called Ki1 lymphoma). Recently, a T-cell lymphoma termed lymphogranulomatosis X (AILD)-type was defined whose chromosomal abnormalities and rearrangement of the beta-chain of the T-cell receptor appear to distinguish it from cases of non-neoplastic lymphogranulomatosis X. Histological and cytochemical criteria enable the identification of many cases of T-cell lymphoma. By contrast, the large number of available monoclonal antibodies can do little more than confirm the T-cell nature and proliferation rate of the tumor cells. DNA rearrangement techniques now make it possible to distinguish between polyclonal and monoclonal T-cell proliferations. Lymphoepithelioid lymphoma, lymphogranulomatosis X and large cell anaplastic lymphoma (Ki1 lymphoma) are treated in detail. The boundary between Hodgkin's disease and peripheral T-cell lymphoma is not as distinct as textbooks would make it appear.     

Rearrangement of T-cell receptor delta chain gene as a marker of lineage and clonality in T-cell lymphoproliferative disorders

We analyzed the rearrangement of T-cell receptor (TcR) delta chain gene in 88 cases of lymphoproliferative disorders; 31 acute lymphoblastic leukemias/lymphoblastic lymphomas (ALL/LBL); 27 adult T-cell leukemias/lymphomas, 9 angioimmunoblastic lymphoadenopathies (AILD); 10 T-cell lymphomas (non-Hodgkin's lymphoma); and 11 Hodgkin's disease. All of 9 T-ALL/LBL cases, of which 4 cases have neither beta nor gamma gene rearrangement, had a new rearranged band of TcR delta locus. Ten of 16 B-lineage ALL/LBL had rearranged band(s) or deletion of TcR delta locus. The rearranged bands were recognized in 2 cases of AILD and 1 case of T-cell lymphoma. All cases of adult T-cell leukemias/lymphomas, 4 of AILD, 4 of T-cell lymphoma, and 8 of Hodgkin's disease had deleted TcR delta locus. Heterogeneous findings of TcR delta locus analysis were observed in AILD, T-cell lymphoma, and Hodgkin's disease. In 16 cases with TcR delta rearrangement, the J delta 1 region was frequently used and the J delta 2 region was rearranged in one AILD. It is suspected that J delta 3 was used in one T-ALL/LBL. There was no correlation between the phenotypic pattern of CD3, CD4, CD8 in T-cell disorders and the rearrangement of the TcR delta gene. These findings suggest that the newly identified TcR delta chain gene rearranges at a very early stage of T-cell ontogeny; prior to the other TcR genes and perhaps at almost the same stage with CD7 expression. The TcR delta gene is useful in assessing clonality for the most immature T-cell neoplasms not showing rearrangement of the other TcR genes. This gene is not lineage specific; however, when used in conjunction with immunoglobulin heavy chain gene, it may be a useful tool to distinguish lymphoid lineage of ALL/LBL.     

Functional and surface phenotype study of lymphocyte subsets in peripheral blood and lymph nodes of breast cancer patients

In an attempt to identify lymphocyte subsets possibly involved in the response to malignant cells, we have studied the lymphocyte surface phenotype by using a panel of monoclonal antibodies on both peripheral blood lymphocytes (PBL) and histologically proven metastatic and nonmetastatic (i.e., "hyperplastic") axillary lymph node lymphocytes (LNL) from eight breast cancer patients. Furthermore, we carried out a functional study by evaluating the response to polyclonal mitogens of the PBL and of the LNL of the same patients. A group of 30 healthy subjects, age and sex matched, were selected as controls for PBL. Six of them, who underwent surgery for nonneoplastic conditions, were selected as controls for LNL. The responsiveness of breast cancer patients' PBL to polyclonal mitogens phytohemagglutinin (PHA) and concanavalin A (Con A) was significantly lower as compared with the control response. The responsiveness of breast cancer patients' metastatic LNL was not different from control LNL for PHA, and it was lower than control LNL for Con A, while the responsiveness of the same metastatic LNL was higher than that of nonmetastatic (i.e., hyperplastic) LNL of patients. Furthermore, the response of hyperplastic LNL was always lower than that of control LNL. The responsiveness of patients' PBL was always lower than that of metastatic LNL, while the responsiveness of patients' PBL vs. hyperplastic LNL was at variance. Regarding the surface phenotype of PBL, there was no difference between those of breast cancer patients and controls concerning the T-cells subsets, while the Leu 7, CD 21 and DR antigens were significantly higher among the breast cancer patients. No significant differences were found between patient metastatic and hyperplastic LNL or between control LNL and patient metastatic or hyperplastic LNL, respectively; only the CD 4 antigen was higher in metastatic than in hyperplastic LNL. A comparison of this surface phenotype between PBL and either metastatic or hyperplastic LNL of breast cancer patients showed values almost constantly significantly higher for PBL vs. either metastatic or hyperplastic LNL, respectively. The results of our study suggest that there is no change in the local-regional immunocompetent cell subsets that may be related to metastasis of breast cancer to regional nodes and to the progression of disease and that circulating T cells in breast cancer include cells expressing activation markers but not showing significant changes in the proportion of entire subpopulations.     

Secondary myeloid/natural killer cell acute leukemia following T-cell lymphoma

A 56-year-old woman was treated with combination chemotherapy and radiation therapy for peripheral T-cell lymphoma. Following complete remission for a period of 6 months, she returned again with marked leukocytosis. Leukemic cells were characterized by scanty cytoplasm with fine azurophilic granules, and were highly positive for myeloperoxidase and sudan black-B. Immunophenotypic analysis revealed that blast cells were positive for myeloid antigens (CD13, CD33), and natural killer (NK) cell antigen (CD56), but negative for T-cell antigens (CD2, CD5, CD7), B-cell antigens (CD19, CD20), CD34, and HLA-DR. The case was diagnosed as secondary myeloid/NK cell acute leukemia following non-Hodgkin's lymphoma. Despite aggressive chemotherapy against leukemia, she died of multiorgan failure 7 months following onset of leukemia. We present, to the best of our knowledge, the first published report of what seems to be a secondary myeloid/NK cell acute leukemia following T-cell lymphoma.     

Histologic, immunophenotypic and genotypic analyses of bone marrow trephines from patients with non-Hodgkin's lymphoma

Marrow involvement in 20 patients with non-Hodgkin's lymphoma (NHL) were studied by histology, immunophenotypic and genotypic methods. Eighteen of these trephines were histologically involved with recognizable lymphomatous infiltrates and five of these were the primary disease site. In the remaining two cases (with histologically involved lymph nodes) the trephines were uninvolved with tumour. Three B-cell cases expressing surface immunoglobulin (sIg) and/or CD37 and one case not analysed phenotypically showed Ig gene rearrangements. The two remaining cases with B NHL showed no gene rearrangements, however, in one of these the trephine was histologically uninvolved with tumour. Twelve out of 14 T-cell cases were characterized by variable or absent expression of one or more T-cell antigens from the tumour population, one case was negative for all T-cell antigens and the remaining case was not histologically involved with tumour. All three lymphoblastic lymphomas and only 4/11 peripheral T-cell lymphomas (PTCL) cases revealed T-cell receptor (TcR) gene rearrangements. One of the latter cases also exhibited Ig J_H gene rearrangements. This study demonstrates the usefulness of bone marrow trephines (BMT) in histologic, phenotypic and genotypic analyses. However, although genotypic data confirm clonality in B NHL and the lymphoblastic lymphomas there was genotypic heterogeneity within the PTCL group.     

Dissociation of caspase-mediated events and programmed cell death induced via HLA-DR in follicular lymphoma

Human leukocyte antigens (HLA) class II antigen-mediated apoptosis has been documented in antigen-presenting cells and B lymphoproliferations. Characteristics of the apoptosis include rapidity and selectivity for mature cells. Follicular lymphomas are particularly refractory to apoptosis. The B-cell lymphoma Ramos shares characteristics of this subgroup and is insensitive to apoptosis via simple HLA-DR engagement. However, oligomerization of HLA-DR antigens induced caspase activation followed by phosphatidylserine externalization, activation of PKC-delta and cleavage of nuclear lamin B. Mitochondrial injury was also detected. However, inhibition of caspase activation simply delayed the apoptotic phenotype but neither protected against cell death nor prevented mitochondrial injury. The data in this report demonstrate that the requirements for the initiating signal (oligomerization versus engagement) as well as the molecular pathways varies between different B lymphoproliferations despite their common expression of HLA-DR. Finally, blockade of caspase activation in parallel with HLA-DR mAb stimulation could provide a potent autovaccination stimulus by leading to necrotic death of B-cell lymphomas.     

Precursor T-cell lymphoma associated with human immunodeficiency virus type 1 (HIV-1) infection. First reported case

The majority of lymphomas that develop in human immunodeficiency virus type 1 (HIV-1) positive patients have a B-cell phenotype, with few reported cases of T-cell lymphoma. Within the latter group, those that have been comprehensively phenotyped had a mature helper T-cell phenotype (CD4+). We report, for the first time, an HIV-1 positive patient with a precursor T-cell lymphoma (CD7+,CD1-,CD3-,CD4-, and CD8-). T-cell receptor beta and gamma genes were in the germline configuration and integration of HIV-1 DNA could not be detected in the lymphoma cell genome.     

Cytotoxic/natural killer cell cutaneous lymphomas. Report of EORTC Cutaneous Lymphoma Task Force Workshop

BACKGROUND: Cutaneous lymphomas expressing a cytotoxic or natural killer (NK) cell phenotype represent a group of lymphoproliferative disorders for which there is currently much confusion and little consensus regarding the best nomenclature and classification. METHODS: This study analyzes 48 cases of primary cutaneous lymphoma expressing cytotoxic proteins and/or the NK cell marker, CD56. These cases were collected for a workshop of the European Organization for Research and Treatment of Cancer Cutaneous Lymphoma Task Force, to better clarify the clinical, morphologic, and phenotypic features of these uncommon tumors. RESULTS: Several categories with different clinical and pathologic features were delineated: 1) aggressive, CD8+, epidermotropic, cytotoxic T-cell lymphoma; 2) mycosis fungoides, cytotoxic immunophenotype variant; 3) subcutaneous panniculitis-like T-cell lymphoma; 4) NK/T-cell lymphoma, nasal type; 5) CD4+, NK cell lymphoma; 6) blastoid NK cell lymphoma; (7) intravascular NK-like lymphoma; and 8) cytotoxic, peripheral T-cell lymphoma. CONCLUSIONS: Our data show that primary cutaneous cytotoxic/NK cell lymphomas include distinct groups of diseases, clinically, histologically, and biologically. Because the finding of a cytotoxic phenotype often has prognostic significance, the routine use of cytotoxic markers in the diagnosis and classification of cutaneous lymphomas should be expanded.     

Distribution and prognosis of WHO lymphoma subtypes in Taiwan reveals a low incidence of germinal-center derived tumors

To assess the distribution of lymphomas in Taiwan according to the WHO (World Health Organization) classification, 175 recently diagnosed cases of malignant lymphomas were studied and the clinicopathologic data were analyzed. B-cell lymphomas accounted for 57.1% of cases, T-cell lymphomas 38.9%, and Hodgkin's lymphoma 4%. Extranodal lymphomas predominated (55.4%). The most common subtype of B-cell lymphoma was diffuse large B-cell lymphoma (33.1%). All tumor types believed to be derived from germinal center (GC) B-cells including follicular lymphoma (4.6%), Burkitt lymphoma (1.7%), Hodgkin lymphoma (4.0%), and GC-like diffuse large B-cell lymphoma (as defined by combined expression of bcl-6 and CD10) were rather uncommon as compared to frequencies seen in series from Western countries. The common T-cell lymphomas included nasal and extranasal NK/T cell lymphoma (7.4%), mycosis fungoides (7.4%), and unspecified peripheral T-cell lymphoma (6.9%). Adult T-cell leukemia/lymphoma was very uncommon and accounts for only 0.6%. The proportional increase in T-cell lymphomas that were unrelated to type I human T-cell lymphotropic virus (HTLV-1) may be linked to differential Epstein-Barr virus (EBV) oncogenesis. The survival data revealed that mantle cell lymphoma, NK/T-cell lymphoma, unspecified peripheral T-cell lymphoma, and subcutaneous panniculitis-like T-cell lymphoma had an aggressive course. Our results confirm the utility of the WHO classification scheme for prognostic stratification and further highlight the distinctive distribution pattern of malignant lymphoma in Taiwan including the higher relative incidence of T cell lymphomas and the rarity of germinal center-derived B-cell tumors.     

Application of Immunophenotyping and Heteroduplex Polymerase Chain Reaction (hPARR) for Diagnosis of Canine Lymphomas

Background: Canine malignant lymphoma is classified into B- or T-cell origin, as in the human case. Due to differences in prognosis, a suitable method needs to be developed for lineage identification. Aims: To determine the accuracy of immunophenotypic and molecular information between three methods: immunocytochemistry (ICC), immunohistochemistry (IHC) and heteroduplex polymerase chain reaction for antigen receptor rearrangements (hPARR) in spontaneous canine lymphomas. Materials and Methods: Peripheral blood, fine needle aspiration and tissue biopsies from enlarged peripheral lymph nodes prior to treatment of 28 multicentric lymphoma patients were collected. Cytopathology and histopathology were examined and classified using the updated Kiel and WHO classifications, respectively. Anti-Pax5 and anti-CD3 antibodies as B- and T-cell markers were applied for immunophenotyping by ICC and IHC. Neoplastic lymphocytes from lymph node and white blood cell pellets from peripheral blood were evaluated by hPARR. Results: In this study, low grade B-cell lymphoma accounted for 25% (7/28), high grade B-cell lymphoma for 64.3% (18/28) and high grade T-cell lymphoma for 10.7% (3/28). According to the WHO classification, 50% of all cases were classified as diffuse large B-cell lymphoma. In addition, ICC showed concordant results with IHC; all B-cell lymphomas showed Pax5+/CD3, and all T-cell lymphomas exhibited Pax5-/CD3+. In contrast to hPARR, 12 B-cell lymphomas featured the IgH gene; seven presented the TCRγ gene; five cases showed both IgH and TCRγ genes, and one case were indeterminate. Three T-cell lymphomas showed the TCRγ gene. The percentage agreement between hPARR and ICC/IHC was 60%. Conclusions: Immunophenotyping should not rely on a single method. ICC or IHC with hPARR should be used concurrently for immunophenotypic diagnosis in canine lymphomas.     

T-cell and NK/T-cell lymphomas in southern Taiwan: a study of 72 cases in a single institute

In an attempt to better understand the clinicopathologic features of T- and natural killer (NK)/T-cell lymphomas in Taiwan and the distribution and relative frequency of each subtype according to the new WHO classification, the pathology file of a medical center in southern Taiwan during 1989-2002 was retrospectively searched. The results of light microscopy, immunohistochemistry, in situ hybridization for Epstein-Barr virus (EBER), and T-cell receptor (TCR)-gamma chain gene rearrangement were correlated with clinical findings. A total of 72 cases were identified. They were peripheral T-cell lymphoma, unspecified (PTLu; n = 23, 31.9%), NK/T-cell lymphoma (n = 14, 19.4%), anaplastic large cell lymphoma (n = 13, 18.0%), angioimmunoblastic T-cell lymphoma (AITL; n = 9, 12.5%), precursor T-lymphoblastic lymphoma (n = 8, 11.1%), enteropathy-type intestinal T-cell lymphoma (n = 2, 2.8%), adult T-cell leukemia/lymphoma (n = 2, 2.8%), and subcutaneous panniculitis-like T-cell lymphoma (n = 1, 1.4%). The male to female ratio was 1.5:1. Forty patients (55.6%) had extranodal presentation. Eleven cases including 9 of 14 (64.3%) NK/T-cell lymphomas expressed CD56. All 14 NK/T-cell lymphomas are EBER-positive. Seven of nine (77.8%) AITLs expressed CD10. The overall 5-year survival rate was 10.2%. In conclusion, we have characterized a large series of T- and NK/T-cell lymphomas in southern Taiwan, where there is male predominance and poor prognosis. CD56 is a specific but not very sensitive marker while EBER is most reliable for the diagnosis of NK/T-cell lymphoma. CD10 is a useful marker to differentiate AITL from PTLu.