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Koichi Ohshima

Publications and source records attributed to Koichi Ohshima.

At least 73 records · Page 4Linked to original sources
PubMed2002

Analysis of novel disease-related genes in bronchial asthma.

Bronchial asthma is a complex disease characterized by airway inflammation involving interleukin (IL)-4 and IL-13. We have applied microarray analyses to human bronchial epithelial cultures to probe for genes regulated by these cytokines and have identified a subset of disease-relevant genes by comparison with cDNA libraries derived from normal and asthmatic bronchial biopsies. Squamous cell carcinoma antigen-1 (SCCA1) and SCCA2, the cysteine and serine protease inhibitors, respectively, showed the highest expression by IL-4 and IL-13, and particularly, SCCA1 was significantly increased in the asthmatic cDNA library. STAT6 was shown to be involved in expression of SCCA1 and SCCA2 in vitro. Furthermore, serum levels of SCCA were also elevated in asthmatic patients. Taken together, it was supposed that SCCA may play some role in the pathogenesis of bronchia asthma, and measuring its serum level may be relevant for diagnosing or monitoring the status of bronchial asthma. In a complex disorder such as asthma, this combination of in vitro and in vivo genomic approaches is a powerful discriminatory method enabling identification of novel disease-related genes and their mechanisms of regulation.

Adolescent↗
PubMed2002

Infiltration of Th1 and Th2 lymphocytes around Hodgkin and Reed-Sternberg (H&RS) cells in Hodgkin disease: Relation with expression of CXC and CC chemokines on H&RS cells.

Hodgkin disease (HD) is characterized by the presence of Hodgkin and Reed-Sternberg cells (H&RS) and a prominent lymphocytic infiltration. Various CXC and CC chemokines [e.g., interferon-gamma-inducible protein-10 (IP10), monokine induced by interferon-gamma (MIG) and TARC] are expressed on H&RS cells. Our study was designed to investigate the expression of MIG, IP10 and TARC on H&RS cells and their relations on lymphocyte infiltration. Immunohistochemical staining was performed using antibodies for CXCR3 (a specific receptor for IP10 and MIG), which is characteristic of Th1 helper phenotype and CCR3, CCR4 and ST2, which are features of Th2 cells. We studied 15 cases of HD [lymphocyte predominance (LP) type, 2; mixed cellularity (MC) type, 6; and nodular sclerosis (NS) type, 7]. All 6 MC cases contained TARC-, IP10- and MIG-expressing H&RS cells, however only 2 of 5 NS cases contained TARC-expressing H&RS cells, 3 of 7 NS contained MIG-expressing H&RS cells and only 1 of 7 NS contained IP10-expressing H&RS cells. Neither of the 2 LP cases contained HR&S cells that expressed these chemokines. The chemokines were more frequently expressed by MC than by NS and LP types. IP10-, MIG- and TARC-positive HD cases contained higher numbers of Th2 lymphocytes (ST2- CCR3- or CCR4-positive lymphocytes), compared to IP10-, MIG- and TARC-negative HD cases (p < 0.05 or <0.5). The number of CXCR3 (MIG and IP10 receptor)-positive lymphocytes (Th1 lymphocytes) was not different between MIG- and IP10-positive and -negative HD. Lymphocytes surrounding MIG- and IP10-positive H&RS cells were more frequently CXCR3-positive, however, compared to MIG- and IP10-negative cases. The CCR4 (TARC receptor)-positive lymphocytes, surrounding H&RS cells, were minority and the surrounding lymphocytes were not different between TARC-positive and negative cases. Our results indicate that MIG, IP10 and TARC chemokines influenced the response of Th2 cells in HD. It is possible, however, that IP10 and MIG may locally influence Th1 cells via cell migration.

CD4 Antigens↗
PubMed2002

CD4-CD8- T-cell polymyositis in a patient with chronic active Epstein-Barr virus infection.

We describe a 17-year-old woman with chronic active Epstein-Barr virus infection (CAEBV), who developed EBV+CD4-CD8- T-cell polymyositis. At 14 years of age, CAEBV was diagnosed with fever, cytopenia, liver dysfunction, and hepatosplenomegaly. Despite the transient remission of interferon-alpha therapy, migratory lesions emerged in back and extremities. MRI indicated polymyositis. Biopsy specimens revealed intramuscular infiltration of CD3+, CD4-, CD8-, CD56-, and EBV-encoded RNA 1+ cells. Circulating CD4-CD8-Vdelta2/Vgamma9 cells increased. gammadeltaT-cells contained 20-200 times higher EBV-DNA (2 x 10(4) copies/microgDNA) than alphabetaT-cells or NK-cells. The ominous polymyositis might denote the musculotropic invasion of EBV+gammadeltaT-cell lymphoproliferative disease as a consequence of CAEBV.

Adolescent↗
PubMed2002

Perforin defects of primary haemophagocytic lymphohistiocytosis in Japan.

The perforin gene was analysed in 15 Japanese patients with primary haemophagocytic lymphohistiocytosis (HLH). Perforin gene defects were found in two out of eight patients with familial HLH (FHL), and one out of seven without affected siblings. Four novel mutations were identified. Compound heterozygous mutations (one FHL and one sporadic HLH) and only one allele mutation (one FHL) were defined. Flow cytometry revealed no perforin expression in CD8+ or CD56+ cells from a surviving patient with a mutation. The frequency of mutation was at least 20% of FHL in Japan. Flow cytometry for intracellular perforin may be useful for the screening of FHL2.

Age of Onset↗
PubMed2002

Expression of cutaneous lymphocyte antigen is associated with a poor outcome of nasal-type natural killer-cell lymphoma.

Nasal and nasal-type natural killer (NK) lymphoma is a distinct clinicopathological entity mostly associated with Epstein-Barr virus. Cases that have widespread lesions are resistant to ordinary anti-cancer therapy and take a highly aggressive course. To date, there are no available data on the relationships between the localization, clinical outcome and expression of adhesion molecules in such cases. We examined the expression of cutaneous lymphocyte antigen (CLA) in 52 cases of NK-cell lymphoma. CLA was highly expressed in cutaneous cases. Also, the CLA+ group (n=29) had a much worse prognosis than the CLA- group (n=23), regardless of the primary site or clinical staging. Univariate analysis identified some significant prognostic factors, and multivariate analysis of these factors showed that the expression of CLA was an independent prognostic indicator. In conclusion, the present findings established that CLA is an independent and important prognostic factor in patients with NK-cell lymphomas.

Adolescent↗
PubMed2002

The World Health Organization classification of malignant lymphoma: incidence and clinical prognosis in HTLV-1-endemic area of Fukuoka.

New insights into the pathogenesis of lymphoid malignancies have been gained through novel genetic, molecular and immunological techniques. A new classification system for lymphoid malignancies, known as the new World Health Organization (WHO) classification, has been proposed recently based on these findings. The relative incidence of the subtypes of malignant lymphoma is known to differ according to geographic location. Adult T-cell leukemia/lymphoma (ATLL) is a human malignancy associated with human T-cell leukemia virus type 1 (HTLV-1), and the Kyushu islands are an HTLV-1 endemic area. To clarify the relationship between the histological classification and prognosis of lymphoid malignancies, we reclassified previous cases in our department and summarized our previous reports using the WHO classification. Of 933 cases of lymphoid malignancies, 471 (50%) were B-cell lymphoma, 396 (42%) T/natural killer (NK)-cell lymphoma and 41 (4%) Hodgkin lymphoma (HL). Analysis of clinical outcome showed favorable prognosis for HL, intermediate for B-cell lymphoma and poor prognosis for T-cell lymphoma. Among B-cell lymphomas, the commonest type was diffuse large B-cell lymphoma (n = 281; 60%). Marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT) was diagnosed in 82 cases (17%), follicular lymphoma in 52 (11%) and mantle cell lymphoma in 24 (5%). Other less common lymphomas were Burkitt lymphoma (n = 9; 2%) and lymphoblastic lymphoma (n = 5; 1%). Using overall survival rates, the various B-cell lymphoma types could be divided into three broad groups for prognostic purposes: (i) low-risk group comprising follicular lymphoma and MALT; (ii) intermediate-risk group comprising diffuse large B-cell lymphoma and Burkitt lymphoma; and (iii) high-risk group comprising mantle cell lymphoma and lymphoblastic lymphoma. Among the T/NK-cell lymphomas, the commonest type was ATLL (n = 191; 48%), followed by peripheral T-cell lymphoma, unspecified (n = 83; 21%), angioimmunoblastic lymphadenopathy with dysproteinemia (AILD) (n = 38; 10%), anaplastic large cell lymphoma (ALCL) (n = 22; 6%). Less common types were lymphoblastic lymphoma (n = 17; 4%), nasal and nasal-type NK/T-cell lymphoma (n = 17; 4%), mycosis fungoides (MF) (n = 9; 2%) and other rare types. With respect to clinical prognosis, T/NK-cell lymphomas fell into three groups: (i) relative low-risk group comprising ALCL, AILD, MF and lymphoblastic lymphoma; (ii) relative intermediate-risk group comprising NK/T-cell lymphoma and unspecified lymphoma; and (iii) extremely high-risk group comprising ATLL. Among the lymphoblastic lymphomas, B-cell type and T-cell type lymphomas exhibited different clinical outcomes. We conclude that the histological, phenotypic and genotypic classification of the new WHO system should be beneficial for the clinical approach to these tumors.

Endemic Diseases↗
PubMed2002

Clinicopathological features of gastric B-cell lymphoma: a series of 317 cases.

The stomach is a common site of extranodal malignant lymphoma. Here we examined the clinicopathological features of 317 gastric B-cell lymphomas and characterized the differences among low-grade mucosa-associated lymphoid tissue (MALT) lymphomas (LG), high-grade MALT lymphomas (HG), follicular lymphomas (FL) and diffuse large B-cell lymphomas (DL). Cases included 126 DL, 71 HG, 98 LG, 10 FL, three Burkitt's lymphoma and nine of undefined type. The age range of patients was as follows: LG, 14-96 years (mean, 61.1); HG, 20-87 years (mean, 63.9); DL, 16-88 years (mean, 62.8); and FL, 54-76 years (mean, 65.5). There were no differences in age with respect to tumor type. There were more women patients with LG (female:male, 55:43), while males predominated among DL patients (54:72). The sexes were represented almost equally in HG cases (34:37). Histological findings, especially in DL tumors, correlated significantly to the gross appearance of mass formation. Dutcher bodies were encountered mainly in HG or LG cases. Our results showed no differences in age, sex or site of disease between LG, HG and DL tumors. However, the grade of malignancy correlated strongly to gross appearance. Dutcher bodies were important for the diagnosis of gastric MALT lymphoma.

Adolescent↗
PubMed2002

Rearrangement of immunoglobulin heavy and light chains and VH family in thyroid and salivary gland lymphomas.

It is often difficult to differentiate extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) from non-neoplastic inflammatory conditions. Demonstration of clonal lymphoid proliferation by molecular procedures is important for accurate diagnosis. We examined the clonal population of B-cell lymphomas in nine cases of thyroid and two cases of salivary gland B-cell lymphoma using semi-nested polymerase chain reaction (PCR)-based assay for IgH gene arrangement and reverse transcription (RT)-PCR single-strand conformation polymorphism (SSCP) for the detection of IgL gene rearrangement. Clonality was evident in nine out of 11 cases of B-cell lymphomas examined by PCR, and in six of eight cases by RT-PCR SSCP. In addition, analysis of VH families was performed in eight cases. Although VH3 family was frequently used, each case demonstrated the VH4, VH5 or VH6 family. It is possible that the normal counterpart of thyroid or salivary gland lymphoma might be different from peripheral blood B lymphocytes, which usually use VH3 family. Our results indicate that although no clonality was noted in one case by both PCR and SSCP, these molecular methods are useful as supplementary diagnostic tests for both thyroid and salivary gland lymphomas.

Adult↗
PubMed2002

Focal follicular features in tonsillar diffuse large B-cell lymphomas: follicular lymphoma with diffuse areas or follicular colonization.

Focal follicular features in diffuse large B-cell lymphomas (DLBCLs) are bound to raise the question of follicular lymphoma (FL) with diffuse areas, because the diagnosis of FL is based on the presence of follicular areas, even though focal. We report 7 cases of primary tonsillar DLBCLs with focal follicular features that presented with morphologic, immunohistochemical, and biological features distinct from those of FL. Histologically, these tumors were characterized by involvement of pericryptal follicles with adjacent dominant diffuse areas. Monomorphous large tumor cells were evenly spaced with abundant, often clear cytoplasm, and blastoid nuclei often with a delicate nuclear membrane. Importantly, residual germinal centers (GCs) were present in the form of either an intrafollicular GC remnant or an isolated GC in the midst of diffuse tumor. An extrafollicular and/or parafollicular growth pattern was also observed. Bcl-6 staining revealed a predominantly sporadic occurrence of Bcl-6(+) cells, comprising <50% of tumor cells, and none displayed diffusely dense collections (>75%) of Bcl-6(+) tumor cells characteristic of the GC or FL. Staining for CD10 was negative in 6 cases. Five of 7 patients were younger than 60, the median age of other patients with primary tonsillar DLBCL. No extratonsillar involvement was seen at 18 months after diagnosis. After chemotherapy or radiotherapy, complete remission was achieved with ease in all patients, but 2 patients who were treated with chemotherapy alone relapsed at 24 and 30 months. In conclusion, tonsillar DLBCL includes a small (10%) but distinct subgroup that warrants distinction from FL with predominant diffuse areas or de novo DLBCL. It appears that the focal follicular features in tonsillar DLBCL likely represent follicular colonization of marginal zone B-cell lymphoma, probably high-grade, if the possibility of FL is excluded.

Adult↗
PubMed2002

Analysis of chromosome 6q deletion in EBV-associated NK cell leukaemia/lymphoma.

Deletions involving chromosome 6q have been reported in a number of human cancers such as ovarian and breast tumours as well as haematopoietic malignancies. It seems that this region might contain tumour-suppressor genes. Putative natural killer cell lymphomas/leukaemias (NKLL) represent a group of recently characterized haematolymphoid malignancies sharing an immunophenotype of CD3/Leu4- CD3epsilon+ CD56+, a genotype of germline T-cell receptor genes, and have a close association with Epstein-Barr virus (EBV). Deletion at 6q21-q25 was demonstrated in three recently reported cases of NKLL. Here we investigated the possible involvement of 6q deletions in the pathogenesis, and especially the tumorigenesis of NKLL. The regions of D6S1574 (6p25), DS276 (6p12), D6S257 (6q11), D6S434 (6q14), D6S287 (6q15), D6S292 (6q21), D6S308 (6q22), D6S264 (6q25), and D6S446 (6q26) were analysed by PCR in 25 cases of NKLL, including seven cases with chronic NK leukaemia, six with acute NK leukaemia and 12 with NK lymphoma. 6q deletions, especially 6q15-25, were frequently detected, but 6p deletions were not detected in any cases. Analysis of 6q21 showed possible deletion in two of seven cases (29%) with chronic NK leukaemia, three of six (50%) with acute leukaemia, and 12 of 12 (100%) with NK lymphoma. The frequency of deletion increased in clinical phases. In three cases with lymphoma, fluorescence in situ hybridisation was performed, which confirmed 6q21 deletion in two cases, although 6q telomeric and centromeric regions were preserved. The other case failed to show deletion. Our results suggest that 6q deletion, especially 6q21-25, might be involved in NKLL tumorigenesis, and support the presence of the tumour suppressor genes associated with the development of NKLL.

Adolescent↗
PubMed2002

Chromosomal and comparative genomic analyses of HHV-8-negative primary effusion lymphoma in five HIV-negative Japanese patients.

A rare subset of HIV lymphoma, known as primary effusion lymphoma (PEL), is a high-grade tumour carrying human herpes virus 8 (HHV-8). Very little is known about genomic aberration in PEL, and only a few HIV-negative PEL have been reported. Here we report the results of chromosomal analysis and comparative genomic hybridisation (CGH) conducted to detect regions of gain and loss, in five HIV-negative Japanese cases of HHV-8-negative PEL. All patients except one (35-year-old female) were elderly men and the morphologic examination showed large cell type. PEL expressed B-cell-associated and activation-associated antigens, and exhibited clonal immunoglobulin genes. No HHV-8 was detected in all four examined cases, but Epstein-Barr virus (EBV) was detected in one case. Genomic abnormalities and aberrations were identified in all HHV-8/HIV-negative PEL. CGH studies showed gain in 19 of 24 chromosomes. Gains of 3q13-27, 8q24, 10q21-23 and Yq were detected in two of the five cases, but other gains were noted in each case. Chromosomal analysis revealed complex abnormalities both in numbers and structures. Burkitt lymphoma-associated t(8;22) was detected in one case, but +8 chromosome and c-myc amplification were detected in the other three cases by Southern blot and/or fluorecence in situ hybridization (FISH). Abnormality of chromosome 8, which associates with c-myc, was detected in four of the five HHV-8/HIV-negative PEL. However, the other common genomic abnormalities of HHV-8/HIV-negative PEL were not detected in our study, but the complex abnormalities seemed to be true rather than the usual large B-cell lymphoma. Our results suggest that multi-step genomic abnormalities might be associated in HHV-8/HIV-negative PEL tumorigenesis.

Adult↗
PubMed2002

Interferon-gamma, interleukin-18, monokine induced by interferon-gamma and interferon-gamma-inducible protein-10 in histiocytic necrotizing lymphadenitis.

Apoptosis of histiocytes is a characteristic feature of necrotizing lymphadenitis (HNL). Recent studies have indicated that Fas and perforin-based pathways are involved in the apoptotic process of HNL. Elevated levels of serum interferon (IFN)-gamma are reported in HNL. The CXC chemokine interferon-gamma-inducible protein-10 (IP-10) and monokine induced by interferon-gamma (MIG) cause tissue necrosis, and interleukin (IL)-18 induces the expression of IFN-gamma and Fas ligand (FasL) by T and natural killer (NK) cells. This study was designed to determine the expression of IFN-gamma, IL-18, MIG and IP-10 in HNL. Ten cases of HNL were analyzed by using immunohistochemical staining and/or reverse transcriptase-polymerase chain reaction (RT-PCR). As a control, we included four cases of non-specific lymphadenitis. MIG and IP-10 proteins, which enhance the release of granzyme, showed a similar distribution pattern in viable tissues surrounding dead tissue, mostly within histiocytes, and lymphocytes in HNL. IL-18 was located within histiocytes, especially phagocytic histiocytes, but not within lymphocytes. In addition, IFN-gamma-positive lymphocytes were frequently detected in the surrounding dead tissue, and the lymphocytes in the same area were frequently positive for CXCR3, a specific receptor of MIG and IP-10. In non-specific lymphadenitis, MIG, IP-10 and IL-18 positive cells were detected, but their numbers were relatively small compared with HNL, while IFN-gamma positive cells were rarely encountered. Our findings suggest that the cytokine and chemokine pathways of IFN-gamma, IL-18, MIG and IP-10 play an important role in the pathogenesis of apoptosis associated with HNL.

Adolescent↗
PubMed2002

Epstein-Barr virus-positive Hodgkin/Reed-Sternberg-like B cell in non-hodgkin lymphoma: nucleotide sequence of the amplified immunoglobulin heavy-chain variable region gene by the single-cell polymerase chain reaction technique.

We examined nucleotide sequences of Epstein-Barr virus (EBV)-positive Hodgkin/Reed-Sternberg (HRS)-like B cells in a case of diffuse large B-cell lymphoma (DLBCL) and a case of adult T-cell lymphoma (ATL) for single-cell polymerase chain reaction of the immunoglobulin heavy-chain gene variable region (VH gene). HRS-like B cells were scattered in the area irrelevant to the lymphoma infiltrates of DLBCL and in the lymphoma area of ATL. HRS-like B cells were positive for CD20 and CD30 but negative for CD15. EBV presented in HRS-like B cells in both cases but not in any lymphoma cells. VH genes of five HRS-like B cells analyzed in DLBCL were polyclonal and showed in-frame sequences with 0% to 2.8% somatic mutation frequency. In an ATL, VH genes of five HRS-like B cells analyzed were polyclonal and somatically mutated. Four cells carried in-frame rearrangements with 3.5% to 17.7% mutation frequency. One of the VH genes has a one-codon deletion. From the fifth cell, an out-of-frame rearrangement with an insertion and a deletion was obtained. Thus, we showed polyclonal EBV-positive HRS-like B cells in both DLBCL and ATL and that whereas EBV-positive, HRS-like B cells in DLBCL exhibited unmutated and mutated VH gene, those in ATL were found to have a somatically mutated VH gene with/without deletions and/or insertions. The HRS-like B cells may appear because of active EBV infection in a patient who is immunosuppressed from the primary lymphoma.

Adult↗
PubMed2002

p53 Gene mutation and genetic instability in superficial multifocal esophageal squamous cell carcinoma.

Tumor multicentricity is occasionally observed in esophageal squamous cell carcinoma (SCC). We studied five surgically resected superficial multifocal esophageal SCCs for p53 gene mutation and genetic instability, using DNA extracted from microdissected areas. A total of 38 target areas (TAs) were analyzed in SCC, dysplasia, basal cell hyperplasia (BCH) and normal squamous epithelium. Analysis of the replication error (RER) at 10 microsatellite loci showed microsatellite instability in all TAs, as well as in normal squamous epithelium. p53 gene mutation was identified in 28.9% (11/38 TAs). All cases showed a common missense mutation in exon 8 at codon 273 (CGT-->CAT, Arg-->His), which was DNA contact mutation in the S10 beta strand. In association with microsatellite alterations, 7 of 9 TAs with p53 mutation in exon 8 at codon 273 also showed loss of heterozygosity (LOH) of p53 gene. LOH of p53 gene was detected in 83.8% (31/37 TAs). LOH at D2S123 on 2p16 near MSH2 gene and at D3S1611 on 3p22 near MLH1 gene was detected in 65.4% (17/26) and 71.4% (10/14) TAs, respectively. Frequencies of LOH at p53 and D2S123 were similar in non-cancerous areas and SCCs. LOH of p53 and D2S123 were found in 50% (5/10 TAs) of non-cancerous areas and 60% (9/15 TAs) of SCCs. Our results suggest that genetic instability induces esophageal tumor multicentricity, and that p53 gene contact mutation together with LOH are early events of the multistage carcinogenesis of multifocal primary esophageal SCC.

Carcinoma, Squamous Cell↗
PubMed2002

Overexpression of heterogeneous nuclear ribonucleoprotein B1 in lymphoproliferative disorders: high expression in cells of follicular center origin.

It is reported that overexpression of hnRNP A2 and B1 proteins is useful for detecting early cancers, and that B1, a splicing minor isoform of A2, is more specific than A2. The B1 expression is still undetermined in human lymphoid tissues. We quantitatively studied the B1 expression in 85 lymph node specimens, comprising reactive lymphoid hyperplasia (RLH; n=8), B-cell lymphoma (n=23), T-cell lymphoma (n=22), and metastatic carcinoma (n=32). Immunostaining and immunoblotting analyses with an anti-B1 monoclonal antibody, 2B2 were performed, and the two sets of results correlated with each other (p<0.05). In RLH specimens, B1 expression rate was significantly higher in follicular centers (FC; 44%) than in mantle zone (MZ; 15%) and paracortex (16%) (p<0.01). B1 expression was statistically higher in B-cell lymphoma than in T-cell lymphoma (p<0.01). In B-cell lymphomas, B1 expression rates were 51% in diffuse large B-cell lymphoma (DLBL; n=5) and 45% in follicular lymphoma (FL; n=16), and they were almost the same as that of the FC. Especially in DLBLs, CD10+ FC-origin lymphomas expressed greater amount of B1 than CD10- non-FC-origin lymphomas. B1 expression rate was low in mantle cell lymphoma (MCL; n=2) and similar to that of MZ in RLH. These results suggest that B1 expression is associated with differentiation in lymphoid tissue rather than transformation. B1 expression increases during the process of B-cell differentiation in the FC, and that high B1 expression is maintained in B-cell lymphomagenesis, especially in cells of FC-origin DLBL.

Adolescent↗
PubMed2002

[Epstein-Barr virus-associated posttransplant lymphoproliferative disease after renal transplantation].

A 24-year-old Japanese male was admitted to our hospital because of lymphadenopathy in his left neck. He had a nine-year history of chronic renal failure, and had received an ABO-mismatched renal allograft and splenectomy in August 2000 after one year of hemodialysis treatment. After renal transplantation, he was treated with FK506, methylprednisolone (mPSL), and mycophenolate mofetil (MMF) as an immunosuppressants for his graft maintenance. On admission, April 2001, he underwent lymphadenectomy, and the immunohistochemical studies revealed that the tumor cells expressed EBV-LMP and EBNA-2 antigens with the histology of diffuse large B-cell lymphoma. Our diagnosis was an Epstein-Barr virus (EBV)-associated posttransplant lymphoproliferative disease (PTLD), and we reduced the dose of immunosuppressive agents and treated the patient with rituximab. In this case, there may have been two principal risk factors associated with PTLD: first, the patient was treated with higher levels of immunosuppressive agents because of the ABO-mismatched transplantation, and second, he was an EBV-seronegative recipient at the time of pretransplantation.

ABO Blood-Group System↗
PubMed2001

Classification of cell lineage and anatomical site, and prognosis of extranodal T-cell lymphoma -- natural killer cell, cytotoxic T lymphocyte, and non-NK/CTL types.

Due to their minority among the non-Hodgkin lymphomas, classification of extranodal T-cell lymphomas, including those of the natural killer (NK) cell type, has long been controversial and unclear, and the clinical outcome is not well clarified. Recently, new well-defined disease entities have been described based on tumor cell biology combined with anatomical site, clinical features, Epstein-Barr virus (EBV) status, and cell lineage as determined by immunophenotype and genotype. Cytological features are usually not specific, and there are no morphologic correlates with the classification of extranodal T/NK-cell lymphomas. From a human T-cell lymphotropic virus type 1 (HTLV-1) endemic area in Japan, we report here the analysis of 144 cases of extranodal T-cell lymphoma, from which fresh tissues were available. As the clinicopathological features were known, we simply reclassified the cases according to cell lineage and anatomical site. The extranodal T-cell lymphomas were classified into three types on the basis of cell lineage: (1) natural killer cell (NK) type [sCD3-, CD56+, T-cell receptor gene (TCR) germline], (2) cytotoxic T lymphocyte (CTL) type [sCD3+, TIA-1+, TCR rearranged, CD8+/-, CD4-/+], and (3) non-NK/CTL type [sCD3+, TIA-1-, TCR rearranged, CD4+/-, CD8-/+]. In addition to cell lineage, the anatomical site and clinical features were added for subclassification. NK type tumors (35 cases) included the lymphoblastic type, nasal/nasal-type NK lymphoma, and NK leukemia. The CTL type (46 cases) included anaplastic large cell lymphoma (ALCL), cutaneous type, intestinal, gamma delta T-cell type, and an unspecified type. The non-NK/CTL type (63 cases) included adult T-cell leukemia/lymphoma (ATLL), mycosis fungoides (MF), and an unspecified type. With the exception of ATLL and MF, most extranodal T-cell lymphomas had a cytotoxic phenotype of NK type or CTL type and were often associated with EBV infection. MF and the unspecified type within the non-NK/CTL tumors, with the exception of ATLL, had a favorable prognosis. However, NK and CTL types, with the exception of ALCL, were associated with a poor prognosis. Our results indicate that anatomical site and cell lineage are useful predictors of clinical outcomes of extranodal T-cell lymphomas.

Antigens, CD↗