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PubMed1985

Cytotoxicity of monoclonal antibodies against individually immunophenotyped human leukemic cells.

Peripheral blood and bone marrow mononuclear cells from 12 patients with acute myeloid leukemia (AML), 2 patients with acute lymphatic leukemia, and 1 patient with chronic myeloid leukemia in blastic crisis were taken at diagnosis or in relapse. Cells were immunophenotyped with a panel of monoclonal antibodies (Moab) (OKIa, Leu M1, Leu M2, Leu M3, Leu M4, B1, Okt 11, J5) and the same antibodies were used in an in vitro cytotoxicity test. Of the 14 patients, 10 had antibody-binding cells, and the percentage of lysed cells was almost equal to that of blasts. The other 4 patients had few binding cells and little lysis. Acute leukemia with and without preceding myelodysplastic features did not differ in immunophenotype. Mean spontaneous release of 51Cr was 12.7% and complement alone caused an additional average release of 11.8%. Four single antibodies together with complement showed a mean 51Cr release of 0.7-32.4% above that found with complement alone. Combinations of Moabs resulted in 51Cr release at least 10% above the single most efficient Moab in 8 out of 12 patients. Not all blast cells showed antibody binding, nor were all antibody-binding cells susceptible to cytotoxicity. Normal bone marrow growth in vitro seemed to be stimulated by factors in complement and in the Moab. When this stimulation was compensated for by adding fetal calf serum, cytotoxicity tests prior to CFUc assays resulted in a mean decrease of 46% of colonies and 25% of clusters in normal bone marrow. CFUc are thus sensitive to the cytotoxicity, although CFU may also be resistant.

Antibodies, Monoclonal↗

PubMed1989

Immunoglobulin and T cell receptor gene rearrangements and in situ immunophenotyping in lymphoproliferative disorders.

We investigated for rearrangements of the immunoglobulin (Ig) heavy and light chain genes and of the T cell receptor gamma (TCR gamma) and beta (TCR beta) genes 45 biopsy samples from a variety of lymphoproliferative disorders. They were diagnosed histopathologically and immunophenotypically as non-Hodgkin's lymphomas (NHLs) of the B cell type (19 cases), NHLs of the T cell type (3 cases), NHLs of "undetermined" cell type (3 cases), atypical lymphoid proliferation (1 case) and AIDS-related lymphadenopathies with florid polyclonal follicular hyperplasia (19 cases). A monoclonal proliferation of B cells was shown by DNA analysis in all 19 B cell NHLs. In two immunohistologically determined T cell NHLs (both diagnosed as mycosis fungoides) the cells had rearrangements of TCR beta gene, whereas in the third case (lymphoblastic NHL) the cells had rearrangements of Ig heavy chain and TCR gamma and TCR beta genes. None of the B cell NHLs exhibited TCR gamma and TCR beta gene rearrangement bands. All the "undetermined" cell NHLs demonstrated rearrangements of Ig heavy chain gene associated with the germ line TCR gamma and TCR beta genes; in two cases light chain gene rearrangements were also found. The atypical lymphoid proliferation, in which the differential diagnosis was between a reactive or malignant process, and two out of 19 cases of florid polyclonal follicular hyperplasia showed a clonal B cell population by DNA analysis. This study indicates that there was a strong correlation between the rearrangements of specific genes and the immunophenotype of the NHL; moreover, DNA analysis of tissue biopsy specimens from phenotypically "undetermined" cell NHLs and from equivocal lymphoid proliferation using Ig and TCR gene probes yielded an answer in the cases analyzed. The significance of clonal B cell expansions found in two AIDS-related lymphadenopathies should be interpreted with caution.

AIDS-Related Complex↗

PubMed1992

Nodular sclerosing Hodgkin's disease and large cell lymphoma. Immunophenotypic characterization of a composite case.

Composite lymphomas have rarely been reported in Hodgkin's disease (HD), except in the lymphocyte predominance sub-type, and immunohistochemical investigations have been performed in only few cases. We describe the histological and immunophenotypical findings in a case of composite nodular sclerosing HD and high-grade, large cell non-Hodgkin's lymphoma (NHL). In our case HD and NHL cells displayed striking morphological and immunophenotypical divergence, suggesting a lack of correlation between the two neoplasms.

Adult↗

PubMed1996

Combined immunophenotyping and FISH with sex chromosome-specific DNA probes for the detection of chimerism in epidermal Langerhans cells after sex-mismatched bone marrow transplantation.

Langerhans cells (LC) of the skin represent bone marrow-derived dendritic antigen-presenting cells and are therefore important in pathophysiological processes such as rejection, graft-versus-host disease, and graft-versus-leukemia-reaction after bone marrow transplantation (BMT). For understanding of these diseases, the evaluation of the chimeric status of LC following BMT is of great interest. To analyze the sex chromosome constitution of LC in the skin, we established a modified and refined technique of combined immunophenotyping and fluorescence in situ hybridization (FISH) and investigated frozen sections of skin biopsies from nine patients after allogeneic sex-mismatched BMT and of two healthy donors for control. LC were specifically labeled using a fluorescent CD1 a antibody and hybridized simultaneously with X and Y chromosome-specific DNA probes. The results of this practical application on nine leukemia patients show the appearance of donor-type LC and the persistence of host-type LC at various times (36 up to 1395 days) after sex-mismatched BMT. Complete chimerism of LC could not be detected in any case. The frequency of recipient-specific LC ranged from 7% to 92% and showed no correlation with time postgrafting. We conclude from our results of 1461 analyzed LC that combined immunophenotyping and interphase cytogenetic analysis by FISH is the method of choice for the assessment of chimerism in a particular cell type after sex-mismatched BMT. Its practical application on other tissues affected by BMT-related pathophysiological processes reveals further knowledge of the time-dependent course of chimeric patterns after BMT.

Acute Disease↗

PubMed1990

Malignant lymphoma involving a Warthin's tumor: a case with immunophenotypic and gene rearrangement analysis.

We describe a Warthin's tumor which was involved by malignant lymphoma. The lymphoma was classified in the Working Formulation as follicular and diffuse, mixed small cleaved and large cell type. Frozen section immunohistochemical studies revealed an abnormal immunophenotype: immunoglobulin-negative and B-lineage. Gene rearrangement analysis confirmed the diagnosis by demonstrating rearrangements of both the immunoglobulin heavy and kappa light chain genes. The bcl-2 gene was also rearranged, consistent with the presence of the t(14;18) (q32;q21) translocation which is typically seen in follicular lymphomas. The T-cell receptor beta chain gene retained the germline configuration. The results in this case highlight an advantage of molecular techniques as compared with immunophenotypic analysis: gene expression is not required to demonstrate clonality.

Adenolymphoma↗

PubMed1988

Lymphocyte immunophenotyping of B-cell lymphomas: a flow cytometric analysis of neoplastic and nonneoplastic cells in 271 cases.

We have reviewed our experience with 271 B-cell lymphomas to determine the effectiveness of flow cytometry in the characterization of these malignancies. Flow cytometric immunophenotyping of the total lymphocyte and/or large lymphocyte populations confirmed the morphologic diagnosis of B-cell lymphoma in 92% of cases, which included 79% monoclonal and 13% surface immunoglobulin (SIg)-negative lymphomas. Light chain monoclonality was most frequent in low grade and follicular center cell (FCC) lymphomas, while SIg-negative cases were most common in high grade and non-FCC types. Low grade lymphomas of all histologic types had high median percentages of neoplastic cells and low T-cell percentages. Conversely, high grade lymphomas exhibited lower and less uniform median percentages of B-cells, with higher numbers of T-cells and lower CD4/CD8 ratios than low grade lymphomas. Several differences in B- and T-cells were observed between specific high grade histologic types. FCC lymphomas with a diffuse pattern had lower percentages of CD4+ cells and lower CD4/CD8 ratios than cases with a follicular pattern. Thus, immunophenotypic differences were observed between histologic types or groups with known differences in clinical course and prognosis. We conclude that flow cytometry provides reliable information on neoplastic and nonneoplastic cells in lymph nodes involved by B-cell lymphomas.

Antigens, Differentiation↗

PubMed1989

Procedural guidelines for performing immunophenotyping by flow cytometry.

Flow cytometry is a rapidly expanding technology that is moving from the research laboratory into the clinical laboratory. Recent advances in availability and reproducibility of monoclonal antibody reagents specific for a wide range of cell types coupled with lower costs for increasingly automated flow cytometers with powerful and user friendly data analysis capabilities have made flow cytometry the method of choice for immunophenotyping in the clinical laboratory. However, there is great variability in the level and type of quality assurance procedures used from laboratory to laboratory. A subcommittee established by the National Committee for Clinical Laboratory Standards (NCCLS), composed of representatives from industry, academia, professional societies, and regulatory agencies, has drafted consensus procedures which address specific problems and suggested solutions for performance of immunophenotyping by flow cytometry. This paper is based on the authors' discussions with the NCCLS Committee but does not represent an official NCCLS position. The official NCCLS document on this subject (H42) is expected to be published in 1989.

Adult↗

PubMed1989

Department of Army lymphocyte immunophenotyping quality assurance program.

With the emergence of the human immunodeficiency virus (HIV) epidemic, lymphocyte immunophenotyping has become the single most important laboratory test for clinical management of HIV-infected subjects. To meet this challenge, the department of Army instituted a multicenter lymphocyte immunophenotyping quality assurance (QA) program in March 1986. An integral part of the QA program has been the development of a monthly proficiency testing program to survey the degree of precision and reproducibility of lymphocyte subset determinations within the Army. After 15 months of proficiency testing, the multicenter cumulative average standard deviation for the percentage of positive CD2 was 3.3, CD3 was 4.4, CD4 was 3.3, CD8 was 3.6, CD8*CD3 was 2.8, CD19/20 was 2.9, and 3.0 for natural killer (NK) cells. The cumulative average coefficient of variation for the percentage of positive CD2 was 3.9%, CD3 was 4.9%, CD4 was 6.6%, CD8 was 11.4%, CD8*CD3 was 9.4%, CD19/20 was 18.8%, and 26.5% for NK. Five survey shipments were also shipped to an additional 49 laboratories outside the Department of Army. The difference of the mean Army percentage positive values from the mean overall percentage positive values ranged from zero to 9.6, with an average difference of 1.6. The interlaboratory variability of flow cytometrically-derived percentage values presented in this report are almost half that cited by other multicenter lymphocyte comparative studies.

Acquired Immunodeficiency Syndrome↗

PubMed1990

Hodgkin's disease followed by lymphomatoid papulosis. Immunophenotypic evidence for a close relationship between lymphomatoid papulosis and Hodgkin's disease.

The clinical association of lymphomatoid papulosis and Hodgkin's disease and the striking morphologic similarity of atypical cells in lymphomatoid papulosis to Reed-Sternberg cells in Hodgkin's disease suggest that lymphomatoid papulosis and Hodgkin's disease are related. To test this possibility we studied the antigenic profile of Reed-Sternberg cells in the lymph nodes and of atypical cells in cutaneous lesions of lymphomatoid papulosis in two patients with Hodgkin's disease and lymphomatoid papulosis. In paraffin sections both cell types expressed CD30, CD45 T cell-restricted antigens, and occasionally CD15 antigens. They were negative for CD45 B cell-restricted antigens and for lysozyme. In cutaneous lymphomatoid papulosis lesions a similar immunologic profile of the atypical cells was found; that is, they were positive for CD30, CD2, CD3, and CD25 but negative for B cell and macrophage antigens. The similarity of the immunophenotype of Reed-Sternberg cells in lymph nodes affected by Hodgkin's disease and the immunophenotype of atypical cells of lymphomatoid papulosis lesions in the same patients suggests that the malignant cells in both conditions are derived from activated T cells and that they are closely related if not identical.

Adult↗

PubMed2005

A der(19)t(12;19)(q12;p13.3) in a case of pediatric acute leukemia with unusual immunophenotype.

We describe a case of acute leukemia in a child with an unusual immunophenotype and a novel cytogenetic abnormality. The leukemia blasts expressed myeloid, natural killer and B-lineage associated antigens. Cytogenetics showed the presence of a novel unbalanced chromosomal translocation, der(19)t(12;19)(q12;p13.3). The patient achieved and maintained remission with myeloid-directed chemotherapy. The differential diagnosis of the immunophenotype and the potential fusion genes are discussed.

Acute Disease↗

PubMed2003

Value of combined morphologic, cytochemical, and immunophenotypic features in predicting recurrent cytogenetic abnormalities in acute myeloid leukemia.

To evaluate the reliability of previously described morphologic, cytochemical and immunophenotypic criteria for the identification of acute myeloid leukemias (AMLs) with t(8;21), inv(16)/t(16;16) and t(15;17), 300 cases were reviewed retrospectively. Eighteen AMLs with features of t(8;21), 31 with features of inv(16)/t(16;16), and 22 with features of t(15;17) were identified. Cytogenetic studies were available for 228 cases and identified 15 cases of t(8;21), 30 cases of inv(16)/t(16;16), 18 cases of t(15;17) and 11 cases 11q23 AML. The true positive rate for pre-cytogenetic evaluation was 95% for t(15;17), 88% for inv(16)/t(16;16) and 87.5% for t(8;21). No difference in 5-year survival was identified in the precytogenetic and corresponding cytogenetic disease groups. No specific features to predict 11q23 abnormalities were identified. This study confirms the reliability of a combined morphologic, cytochemical and immunophenotypic approach to the initial classification of AML. Cytogenetic studies are still needed on all cases to identify the small proportion of cases that will be missed by these methods and to identify other significant cytogenetic abnormalities in AML.

Acute Disease↗

PubMed1988

Immunophenotyping of hematopoietic malignancies in paraffin sections.

Immunophenotyping of hematopoietic malignancies is usually accomplished in frozen sections or cell suspensions. To determine whether this procedure was also feasible in paraffin sections, we performed a double-blind immunoperoxidase study of 65 hematopoietic tumors whose phenotypes had been determined previously in fresh tissue. A selected antibody panel was used, including anti-LN2, UCHL-1, anti-cathepsin B, anti-Leu M1, anti-MB2, and anti-MT1. A correct phenotype was obtained on paraffin sections in 95% of cases. All 31 B-cell malignancies were properly classified, showing reactivity for LN2 and MB2. In 14 of 15 T-cell hematopoietic malignancies, all cells reacted with anti-MT1 and/or UCHL-1; the 1 case negative for these antigens was misdiagnosed as a B-cell tumor because of misinterpreted LN2 reactivity in benign histiocytes. Four of 5 true histiocytic neoplasms were positive for cathepsin B and LN2 but lacked other antigens; the fifth case was wrongly considered a B-cell proliferation because only bland histiocytes displayed cathepsin B. Only 1 of 7 Hodgkin's lymphomas was misdiagnosed (as a T-cell tumor); in the other 6 cases, Reed-Sternberg cells were reactive for LN2 and LEU M1. Five of 6 extramedullary myeloid leukemias also stained for LN2, MT1, and LEU M1. One showed LN2, MB2, and MT1; this case was classified as a B-cell neoplasm and indeed represented a pre-B-cell transformation of chronic myelogenous leukemia. These results show that the specified panel of antibodies may be useful for immunophenotyping of hematopoietic neoplasms when only paraffin sections are available for analysis. However, it cannot supplant traditional cell-marker studies of hematopoietic tumors because of its lesser accuracy.

Antibodies, Monoclonal↗

PubMed1988

Immunophenotype of clonogenic cells in myeloid leukaemia.

Leukaemic clonogenic cells, capable of forming colonies of blast cells in an in-vitro assay, were examined for surface antigen expression using a panel of monoclonal antibodies (Mabs) to stem cell and myeloid differentiation antigens in nine cases of acute myeloid leukaemia (AML) and four cases of chronic myeloid leukaemia in myeloid blast crisis (CML-MBC). Clonogenic cells were found to be most frequently positive with anti-HLA-DR (positive in 100% cases) and RFB-1 (71%) Mabs, with significant reactivity also being seen with CD-33 (69%) and CD-13 (61%) myeloid specific antibodies. CD-11b and CD-15 antigens, expressed predominantly on mature leucocytes, were not significantly expressed on the clonogenic population. Interestingly, the CD-34 antigen, detected by MY-10 Mab on normal myeloid progenitor cells, was demonstrated on the clonogenic fraction of only one of seven cases tested. A discrepancy between antigen expression of clonogenic cells and immunophenotype of the total leukaemic population was frequently seen, with "early" markers (CD-33, HLA-DR, RFB-1) expressed on a higher proportion of the clonogenic fraction than the overall population, while the converse was the case for the "later" marker, CD-11b. Based on the known normal distribution of differentiation antigens, particularly the CD-13 antigen, cases could be ranked according to clonogenic phenotype into immature (CD-13- HLA-DR+ CD-33+ or CD-33-; five cases), and mature (CD-13+ HLA-DR+ CD-33+; eight cases), levels. However, there was no correlation between these maturation levels and the morphology according to the FAB classification. Of note, the mature group included three CML-MBC, as well as two AML cases with a history of myelodysplasia or myeloproliferative disorder. These immunophenotypic findings indicate a heterogeneity in the level of maturation of the clonogenic population, not only in cases of de-novo AML, but also in AML thought to derive from multipotential stem cells.

Adult↗

PubMed1987

Genotypic monoclonality in immunophenotypically polyclonal orbital lymphoid tumors. A model of tumor progression in the lymphoid system. The 1986 Wendell Hughes lecture.

Molecular genetic (genotypic) analysis elucidates gene rearrangements within lymphocytes that are responsible for either immunoglobulin production in B-lymphocytes or the expression of cell-surface antigen recognition receptors in T-lymphocytes. Molecular genetic analysis is far more sensitive than immunophenotypic methods for the detection of small clones of lymphocytes because as few as 2 to 5% of cells in an infiltrate can be discovered to possess the same rearranged DNA sequences with genetic probes. In truly polyclonal proliferations, each lymphocyte reorganizes its immunoglobulin or T-antigen receptor genes in a unique manner, resulting in an almost infinite number of combinations of genetic rearrangement and the absence of any new hybridizing bands upon Southern blotting. In monoclonal proliferations, a new, homogeneous, nongermline band is identified on Southern blotting because a sufficiently large number of lymphocytes exhibit an identical genetic rearrangement. In a group of five orbital lymphoid tumors that appeared to be benign reactive hyperplasias by light microscopy and that were polyclonal by immunophenotypic methods, three were found by molecular genetic analysis to harbor small clones of B-lymphocytes with new rearrangement bands on Southern blotting. No clonal abnormalities of T-lymphocytes were found in these five lesions, despite the fact that they were the preponderant cells in the tumors. These observations suggest that "reactive lymphoid hyperplasia" of the orbit may be an unstable lesion, owing to a T-cell immunoregulatory imbalance, with the potential for developing clonal expansions of B-lymphocytes that nonetheless usually remain localized to the orbit.

DNA↗

PubMed1988

Benign and malignant forms of erythroderma: cutaneous immunophenotypic characteristics.

In order to determine if immunohistologic features are useful in distinguishing benign from malignant types of erythroderma, we studied the immunophenotype of lesional T cells in 20 patients (8 mycosis fungoides/Sézary syndrome, 12 benign) and found them to be generally similar. In all cases, the majority of T cells were Leu-1+, Leu-4+, and Leu-5+, as is typical of mature T cells. Although in most cases a majority of Leu-3+ (helper/phenotype) T cells were present, in 2 there was a majority of the Leu-2+ (cytotoxic/suppressor) subset and in 12 others, a significant minority (20%-40%) of these cells. Low percentages of Leu-2+ cells (less than or equal to 10%), resulting in high Leu-3+/Leu-2+ ratios, did not distinguish benign from malignant erythroderma. Leu-8 antigen deficiency was common in both mycosis fungoides/Sézary syndrome and benign cases (62% vs 75%, respectively). In contrast, Leu-9 antigen deficiency was present in only one patient in each group. The lack of combined Leu-8/9 antigen deficiency in our patients may be due to a heavy inflammatory T cell component, obscuring the antigen deficiencies seen in most nonerythrodermic mycosis fungoides cases. We conclude that immunophenotypic studies with the use of the current antibody panel show many similarities between benign and malignant forms of erythroderma, as well as some minor differences that may prove diagnostically useful if corroborated by future studies.

Antibodies, Monoclonal↗

PubMed2002

Birth characteristics, maternal reproductive history, hormone use during pregnancy, and risk of childhood acute lymphocytic leukemia by immunophenotype (United States).

OBJECTIVE: To investigate the associations of birth characteristics and maternal reproductive factors with risk of childhood acute lymphoblastic leukemia (ALL) by immunophenotypic subtypes. METHODS: Data collected from a case-control study including 1842 ALL cases (age < 15 years) and 1986 individually matched controls were analyzed. Exposure information was obtained through telephone interviews of parents. RESULTS: Factors associated with risk of ALL from all subgroups combined included high birth weight (OR = 1.4, 95% CI = 1.1-1.8), high birth order (OR = 2.0, 95% CI = 1.3-3.0 for fourth-born child compared to first-born child). young maternal age (<20 compared to 25-29, OR = 1.4, 95% CI = 1.1-1.9), advanced paternal age (>39 compared to 25-29, OR = 1.4, 95% CI = 1.0-1.9), induced abortion prior to the index pregnancy (OR = 1.2, 95% CI = 1.0-1.4), and oral contraceptive use during the index pregnancy (OR = 1.5, 95% CI = 1.0-2.2) with children under the age of 2 (OR = 5.1, 95% CI = 1.0-24.7) being the predominantly affected group. Risk of early pre-B-cell ALL increased with advanced paternal age (OR = 1.7, 95% CI = 1.1-2.7) and high birth order (OR = 2.0, 95% CI = 1.1-3.6), while risk of pre-B-cell ALL increased with both younger (OR = 3.4, 95% CI = 1.4-8.4) and advanced maternal age (OR = 2.6, 95% CI = 1.1-5.9). T-cell ALL was associated with high birth weight (OR = 2.4, 95% CI = 1.1-5.5) and history of induced abortion (OR = 2.4, 95% CI = 1.3-4.5). CONCLUSION: This study suggests that the association of ALL with birth characteristics and maternal reproductive factors varies with the immunophenotype of the ALL. Future studies are needed to better understand the effect of maternal hormone in the development of subtype of childhood ALL.

Abortion, Spontaneous↗

PubMed1999

Acute lymphoblastic leukemia with the (8;14)(q24;q32) translocation and FAB L3 morphology associated with a B-precursor immunophenotype: the Pediatric Oncology Group experience.

Five pediatric patients are described with acute lymphoblastic leukemia (ALL) who at presentation had clinical findings suggestive of B cell ALL and lymphoblasts with FAB L3 morphology and the characteristic t(8;14)(q24;q32). However, the leukemia cells of all five patients failed to express surface immunoglobulin (sIg) and kappa or lambda light chains. Based on initial immunophenotyping results consistent with B-precursor ALL, four of these cases were initially treated with conventional ALL chemotherapy. These four patients were switched to B cell ALL treatment protocols once cytogenetic results became available revealing the 8;14 translocation. The fifth case was treated with B cell ALL therapy from the outset. Four of the five patients are in complete remission at 64, 36, 29 and 13 months from diagnosis. One patient relapsed and died 6 months after initial presentation. These five unusual cases with clinical B cell ALL, the t(8;14), and FAB L3 morphology, but negative sIg, demonstrate the importance of careful and multidisciplinary evaluation of leukemic cells with morphology, cytochemistry, immunophenotyping and cytogenetic analysis. Future identification of patients with this profile will allow us to expand our knowledge regarding prognostic significance and optimal treatment for this rare subgroup of patients.

Adolescent↗

PubMed2003

Subcutaneous panniculitis-like T-cell lymphoma: a clinicopathological, immunophenotypic and molecular analysis of six patients.

BACKGROUND: Subcutaneous panniculitis-like T-cell lymphoma (SPTCL) is a rare cytotoxic T-cell lymphoma of the skin. In the World Health Organization classification of T-cell and natural killer cell lymphoma it is listed as an example of extranodal lymphoma. In practice, however, it is most likely to present to a dermatologist. OBJECTIVES: To describe the clinicopathological, immunophenotypic and molecular features of six U.K. patients with SPTCL. METHODS: The clinical, histological and immunophenotypic features were reviewed. T-cell receptor (TCR) gene analysis was performed on blood and tissue samples using polymerase chain reaction/single-strand conformational polymorphism analysis of the TCR-gamma gene using consensus primers. In situ hybridization was performed on lesional skin to detect mRNA for Epstein-Barr virus (EBV). RESULTS: All patients presented with subcutaneous nodules, plaques or ulceration, and three had systemic symptoms. All biopsies exhibited an infiltrate of medium to large pleomorphic cells involving the subcutis with characteristic rimming of fat spaces. Five showed areas of necrosis, but only one showed marked cytophagia. In three cases the neoplastic cells did not express TCR-beta. One was strongly p53 positive, and the other two were CD56 positive. Both these patients showed epidermal involvement with lichenoid changes histologically, and both developed the haemophagocytic syndrome. The other three cases were TCR-beta positive, CD8 positive and CD56 negative. All cases were positive with pan T-cell markers and also for the cytotoxic granule protein T-cell intracellular antigen-1 and granzyme B. All cases were EBV negative both by immunostaining (latent membrane protein-1) and by in situ hybridization (EBV-encoded mRNA). TCR gene analysis revealed a T-cell clone in four of five cases; two of these patients had an identical T-cell clone in the peripheral blood. The median survival was 16 months. However, two of the three TCR-beta-negative patients have died, whereas none of the TCR-beta-positive patients has died. CONCLUSIONS: This is the first series of SPTCL patients to be reported in the U.K. and the data support the view that there are two subsets of SPTCL: those derived from gammadelta T cells which carry a poor prognosis, and are usually CD56 positive, and a more indolent group derived from alphabeta T cells.

Adult↗