Histopathology and immunohistochemistry of peripheral T cell lymphomas: a proposal for their classification

Primary pulmonary Hodgkin's disease

Primary pulmonary Hodgkin's disease is a rare but distinct entity, to be distinguished from nodal Hodgkin's disease and from lymphomas involving the lung secondarily. Sixty-one cases have now been reported in the world's literature. This lymphoma affects women more frequently than men, and typically involves the superior portions of the lungs. Radiologically, it appears as a solitary mass or multinodular disease; inhomogeneity or cavitation of these lesions are common. Since the presentation of this disease is nonspecific, and as noninvasive tests are rarely revealing, diagnosis requires an open thoracotomy and lung biopsy. Factors which correlate with a poorer prognosis include "B" symptoms, bilateral disease, multilobe involvement, penetration of the pleura, and cavitation. The staging and treatment of these lymphomas according to the extent of pulmonary involvement are recommended, as radiotherapy or combination chemotherapy may be effective in appropriately selected patients.

Molecular analysis of a chromosomal translocation, t(9;14)(p13;q32), in a diffuse large-cell lymphoma cell line expressing the Ki-1 antigen

We have studied a translocation, t(9;14)(p13;q32), in a diffuse large-cell lymphoma cell line, KIS-1, that expresses the Ki-1 (CD30) antigen. Molecular cloning of the immunoglobulin heavy-chain locus (IGH) of this cell line revealed an unknown segment linked 5' to IGH. The breakpoint on chromosome 14 was 265 base pairs downstream from the 3' border of the JH6 joining gene segment. Class switch recombination deleted most of the constant genes of IGH (CH) and juxtaposed the C alpha 2 gene downstream of the translocation junction. Analysis of somatic cell hybrids and in situ chromosomal hybridization demonstrated that the translocated segment was normally located at band p13 of chromosome 9. The chromosome 9 sequences were transcriptionally active, giving rise to transcripts of approximately 11 kilobases. The KIS-1 cells seemed to have a small quantity of chimeric transcripts containing both chromosome 9 and C alpha 2 sequences.

Peripheral T-cell lymphomas have a worse prognosis than B-cell lymphomas: a prospective study of 361 immunophenotyped patients treated with the LNH-84 regimen. The GELA (Groupe d'Etude des Lymphomes Agressives)

The prognostic significance of phenotype in malignant lymphomas (ML) is a matter of controversy. Here we analyze the clinical presentation, response to treatment, and survival of the 361 phenotyped patients with ML who were treated by the LNH-84 regimen. Histologic subtypes were diffuse-small cell in 10 patients, diffuse mixed in 69, diffuse large-cell in 177, immunoblastic in 94, and anaplastic large-cell in 11. One hundred and eight patients (30%) had a peripheral T-cell ML and 253 (70%) a B-cell ML. Most of B-cell MLs were of diffuse large-cell type, and the T-cell MLs were distributed among diffuse mixed and immunoblastic subtypes. T-cell MLs had an aggressive presentation with more patients having advanced stage (21% versus 41% stage II, 53% versus 45% stage IV, p = .0002), and B symptoms (58% versus 42%, p less than .01). The only significant difference in clinical manifestations were the higher frequency of gastrointestinal involvement in B-cell MLs (20% versus 2%, p less than .0001) and the more frequent spleen (39% versus 21%, p = .0005) and skin (19% versus 3%, p less than .0001) involvement in T-cell MLs. There was no difference in response to the LNH-84 regiment between the two subgroups, but T-cell ML patients relapsed at a higher rate (43% versus 29%, p less than .001). T-cell ML patients have a significantly shorter freedom-from-relapse (FFR) survival (median: 34 months versus not reached, logrank test: p = .002) and a non-significant shorter overall survival (median: 42 versus 50 months).(ABSTRACT TRUNCATED AT 250 WORDS)

Relationships among expression, transcription and rearrangement of T-cell receptor beta gene in T-cell lymphomas

The expression of T-cell receptors (TCR) in malignant lymphomas was examined immunohistochemically by monoclonal antibodies which react with the TCR beta or TCR delta chain. TCR beta was expressed in 16 out of 47 non-Hodgkin's lymphomas. These included 15 T-cell lymphomas and 1 Ki-1 lymphoma. The anti-TCR beta chain antibody, beta F1, did not react with 26 B-cell lymphomas, 1 Ki-1 lymphoma or 6 Hodgkin's disease. This anti-TCR delta chain antibody, TCR delta 1, did not react with any type of malignant lymphoma. Although TCR beta and CD3 were co-expressed in normal lymphoid tissues and most T-cell lymphomas, 3 cases of CD3+ CD4+ CD8- T-cell lymphoma failed to express TCR beta. TCR beta and Ig JH gene configurations in malignant lymphomas were examined by Southern hybridization. Although each of 9 T-cell lymphomas had a rearranged TCR beta locus, TCR beta gene rearrangement in the 3 cases of beta F1- CD3+ T-cell lymphomas was demonstrated by Southern blot. No transcripts of the TCR beta gene could be found in 2 out of the 3 beta F1- CD3+ T-cell lymphomas by Northern blot, indicating the lack of TCR beta protein expression to be due to non-transcription of the TCR gene. Loss of TCR beta proteins in these T-cell lymphomas is thus quite likely to be associated with T-cell tumour activation and progression, since 3 beta F1- CD3+ T-cell lymphomas expressed CD25 (interleukin-2 receptor) to a high degree.

Large B-cell lymphomas with a high content of reactive T cells

Twenty-one cases of large, B-cell lymphoma with an unusually high content of reactive T lymphocytes are described in this report. Fifteen patients presented with lymphoma in nodal sites and six patients presented with lymphoma in extranodal sites. With two exceptions, all patients were more than 50 years of age. The male to female ratio was 1:2. Histologically, isolated to small groups of large lymphoid cells were intermingled with many small lymphocytes. The large cells were neoplastic and exhibited B-lineage markers; immunoglobulin light chain restriction could be demonstrated in two thirds of the cases. There was a rich infiltrate of immunophenotypically mature T lymphocytes that comprised more than 50% of the cellular population. The T lymphocytes ranged from small cells with dark, round nuclei to slightly larger cells with elongated, irregular nuclei. There were occasional medium-sized blastic cells. There was also a variable infiltrate of histiocytes with or without epithelioid features, eosinophils and plasma cells, and increased vascularity. The peculiar morphologic features were also reproduced in other sites in the four patients for whom additional histologic materials were available for examination. We postulate that the abundance of T cells results either from a florid host reaction or from cytokine secretion by the neoplastic B cells, attracting T cells to the vicinity. The morphologic and immunologic features mimic those of a variety of benign lymphoproliferative diseases, angioimmunoblastic lymphadenopathy and lymphomas arising in angioimmunoblastic lymphadenopathy, peripheral T-cell lymphoma, secondary B-immunoblastic lymphoma, and Hodgkin's disease. Careful morphologic evaluation and immunophenotypic studies using leukocyte antibodies reactive in paraffin-embedded sections are of great assistance in determining a diagnosis.

Prognostic significance of CD30 (Ki-1/Ber-H2) expression in primary cutaneous large-cell lymphomas of T-cell origin. A clinicopathologic and immunohistochemical study in 20 patients

The histologic and immunophenotypical features of 20 primary cutaneous large-cell lymphomas of T-cell origin were investigated and correlated with clinical data to obtain prognostically relevant criteria. Histologic evaluation, using the updated Kiel classification, showed that these large-cell lymphomas represent a morphologic spectrum, often making classification rather arbitrary. It is therefore concluded that the clinical relevance of histologic subtyping is limited for this group of lymphomas. Immunophenotypical studies revealed significant differences between CD30-positive and CD30-negative lymphomas. CD30-positive lymphomas generally presented with localized skin disease, and had a favorable prognosis (9 of 10 patients alive and in complete remission; median survival, 37 months). In contrast, CD30-negative lymphomas often presented with or rapidly developed generalized disease; all patients died of lymphoma (median survival, 17 months). These findings suggest that CD30 expression is an important prognostic parameter for this group of primary cutaneous large-cell lymphomas.

Large cell anaplastic lymphoma of the skin

Large cell anaplastic lymphoma (LCAL) is a recently described entity recognized by its constant expression of the CD30 antigen and by its morphology. LCAL is classified as high grade malignant lymphoma. We report 10 patients with LCAL of the skin, three with primary LCAL and others in which it developed with cutaneous T-cell lymphoma, mainly mycosis fungoides. The immunophenotype in all but one of these cases, was that of activated T cells.

Primary intestinal lymphoma of Ki-1 large cell anaplastic type with mesenteric lymph node and spleen involvement in a renal transplant recipient

A laparotomy performed for an occlusive syndrome, disclosed the presence of an ileal lymphoma in a renal graft recipient, 17 years after a first renal transplant. Mesenteric lymph node and spleen involvement were associated. The morphology of the large cells, the type of infiltration of the lymph node simulating metastatic carcinoma or malignant histiocytosis were highly suggestive of a new type of high grade malignancy lymphoma recently described which is called 'large cell anaplastic ML'. The immunolabelling study confirmed this diagnosis, demonstrating the following phenotype CD4, CD25 (TAC), CD30 (Ki-1), OKT 9 (transferrin receptor), EMA and HLA DR positivity. The tumour cells were negative for the other T, B and histiomonocytic markers. This case, of a large cell anaplastic Ki-1 positive lymphoma, expressing CD4, in a renal graft recipient shows that high grade ML in such patients are not all of the B cell type.

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.

Primary peripheral T cell lymphoma in a kidney transplant under immunosuppression with cyclosporine A

A 56-year-old patient received a cadaveric renal allograft because of primary cystic kidney disease. The donor was a 28-year-old man who died from head trauma. No other major illnesses were present at the time of transplantation. Immunosuppression was performed with cyclosporine A and steroids. After 3 months, the patient presented with fever and abdominal pain which was located in the region of the allograft. Ultrasonography demonstrated a tumor mass at the renal transplant hilus that was suspected to be an infected hematoma. Kidney biopsy from the cortex revealed only severe morphologic signs of cyclosporine A toxicity which was due to high cyclosporine A levels during the first 2 months after transplantation. The patient died from pulmonary embolism 6 months posttransplant. Histologic evaluation of the tumor specimens obtained at autopsy showed an extensive infiltration of the renal hilus and the medulla by a peripheral T cell lymphoma of the large-cell type. The T cell origin was confirmed by immunohistochemistry using the T cell-associated monoclonal antibodies UCHL-1 and MT1.

Expression of growth factor/receptor genes in postthymic T cell malignancies

This study was undertaken to explain the molecular basis for the diverse pathology and clinical behavior of postthymic T cell malignancies. Total cellular RNAs were extracted from four HTLV-1 positive and ten HTLV-1-negative T cell lymphomas and cell lines, and investigated for homology with cloned DNA probes specific for interleukin-2 (IL-2), IL-2 receptor (IL-2R), transforming growth factor beta (TGF-beta), platelet-derived growth factor (PDGF), and epidermal growth factor receptor (EGF-R). Tumor cells associated with clinically high grade HTLV-1-positive adult T cell leukemia (ATL) and large cell morphology (T immunoblastic lymphomas) were found to have higher levels of expression of IL-2 and TGF-beta genes than low grade T cell neoplasms (mycosis fungoides and Sezary's syndrome). High expression of IL-2R gene was restricted to Ki-1-positive lymphomas and to one ATL. Cell lines corresponding to the advanced stage of a cutaneous T cell lymphoma (CTCL) showed enhanced expression of PDGF. Therefore, high grade T cell malignancies had consistently elevated expression of growth factor/receptor (GF/R) genes. Expression of EGF-R was negligible in all T cell malignancies. An inverse relationship was found between the expression of T cell antigen receptor (differentiation antigen) and GF/R (activation antigen) genes, accounting for the frequent aberrant expression of T cell antigens in high grade T cell lymphomas. The results suggest that post-thymic T cell malignancies derived from activated T cells produce and secrete GF, conferring a growth advantage on neoplastic T cells, and correlating well with their histologic subtype and clinical behavior.

Formalin-resistant leukocyte surface antigens in the diagnosis of cutaneous malignant lymphomas

Immunophenotyping of routinely embedded lymphoma biopsies, increasingly used in nodal lymphomas, has not been systematically performed in cutaneous lymphomas. Eight monoclonal antibodies were tested directed against formalin resistant antigens (T cell biased: UCHL1, MT1; B cell biased: 4KB5, L26, Ki-B3; HLA-class II: CBL 120; activation antigens: Ber-H2; myeloid biased: Mac 387, M1) in cutaneous T (N = 29) and B (N = 10) cell lymphomas and pseudolymphomas (N = 9). UCHL1 and MT1 showed a high specificity and sensitivity. B cell-restricted antibodies L26 and 4KB5 showed the best sensitivity and specificity among the B cell-associated antibodies; Ki-B3 showed aberrant expression on T cells in some cases. Ber-H2 (CD30) was demonstrated in most cases of large cell anaplastic lymphoma and single cases of other lymphomas and lymphomatoid papulosis. Class II antigen expression, as determined by CBL 120, showed good specificity but low sensitivity, and antibodies directed against myeloid antigens did not react with tumor cells.

Anaplastic large cell Ki-1 lymphoma. Delineation of two morphological types

This report describes 16 cases of the recently recognized anaplastic large cell Ki-1 lymphoma. The disease showed a male:female ratio of 2.2:1 and a bimodal age distribution with peaks in the third and eighth decades. The clinical presentation was highly variable, with lymph node, skin, bone and gastrointestinal tract being the most commonly affected sites. The lymph nodes usually showed subtotal or sinusoidal involvement, and parenchymal fibrosis was common. The large neoplastic cells were almost invariably admixed with many reactive small lymphocytes, histiocytes and/or neutrophils. Two cytological types could be delineated: type I (pale cell, four cases) consisted of large polygonal cells with distinct pink-staining cell membrane and pale cytoplasm and pleomorphic nuclei showing marked chromatin clearing; and type II (basophilic cell, 12 cases) consisted of round or oval cells with basophilic cytoplasm and/or paranuclear pale hof, pleomorphic nuclei often reniform or lobulated and with frequent multinucleated wreath-like and Reed-Sternberg-like cells. Immunohistochemical studies showed that nine cases (56.3%) exhibited a T-cell phenotype, three cases (18.8%) each exhibited a B-cell or null-cell phenotype, while one case exhibited both T- and B-cell markers. Cutaneous involvement at presentation was associated with a favourable outcome, and spontaneous regression was common. For patients with non-cutaneous presentation, the prognosis was relatively good for young patients treated with aggressive chemotherapy, but was grave for old patients.

Lymphoma phenotyping in formalin-fixed and paraffin wax-embedded tissues: II. Profiles of reactivity in the various tumour types

Recently, monoclonal antibodies capable of phenotyping malignant lymphomas in routinely fixed and processed tissue have become available. Some of these reagents identify lineage-restricted variants of the leucocyte common molecule, whereas others identify unique fixation-resistant epitopes on lymphoid cells, some of which are shared by non-lymphoid tissues. A new generation of antibodies recognizing 'classical' leucocyte antigens such as CD3 are also emerging. Refinements in antigen detection systems, especially for immunoglobulin recognition, combined with these new reagents promise to improve the accuracy of lymphoma diagnosis in routine histopathology. These new antibodies are reviewed, and their limitations, cross reactivities and profiles of staining in lymphoreticular disease are discussed. A strategy for their optimal use is proposed.

Angioimmunoblastic lymphadenopathy. Review of 44 patients with emphasis on prognostic behavior

In order to investigate the relationship between histologic findings and clinical behavior in angioimmunoblastic lymphadenopathy (AILD), 44 patients with AILD were reviewed. These patients comprised 24 men and 20 women with age range from 25 to 84 years of age (median, 64 years). Lymphadenopathy was observed in all patients, systemic in 37, and localized in seven. Polyclonal hypergammaglobulinemia was present in 64% of patients. Histologically clear cells or convoluted cells were observed in 36% and 48% of the patients, respectively. Univariate analysis (log-rank test) for prognostic factors revealed age, appetite, presence of clear cells, or convoluted cells were important factors. However, multivariate analysis revealed that there were no independent factors for prognosis. The presence of clear cells and/or convoluted cells were histologic signs for poor prognosis; autopsy showed that patients with the clear cells with or without convoluted cells mostly died of active disease of AILD with two cases progressing to non-Hodgkin's lymphomas and those with convoluted cells alone died of lung infection. From these findings, AILD could be divided into three groups: AILD with (1) clear cells with or without convoluted cells, (2) convoluted cells alone, or (3) neither cells. The first two groups showed poor prognosis, and the last a favorable prognosis.

What's new in the application of Southern blot analysis of malignant lymphomas?

With the introduction of gene probes for the immunoglobulin and T cell receptor gene segments and the use of the Southern Blot Analysis a new method for the diagnostic characterization of malignant lymphomas was established. Although the method is not absolutely specific for the determination of lineage and clonality of a given lymphoid neoplasm, it provides a lot of additional information for the pathologist. It is the first method that gives proof to the clonality of T cell lymphomas; reactive lymph node processes can be distinguished from true neoplasms; within lymph nodes of mixed lymphoid populations the clonally proliferated can be detected and the lineage can be determined. Therefore the Southern Blot Analysis is a method that should be applied for the diagnosis of malignant lymphomas together with histology and immunohistochemistry. Using the combination of all these methods an extensive characterization of lymphoid neoplasms can be made.

Aberrant phenotypes in peripheral T cell lymphomas

Seventy six peripheral T cell lymphomas were examined immunohistologically to test their reactivity with a panel of monoclonal antibodies against 11 T cell associated antigens (CD1-8, CD27, UCHL1, and the T cell antigen receptor). Sixty two (82%) lymphomas showed aberrant phenotypes, and four main categories were distinguished as follows: (i) lack of one or several pan-T cell antigens (49, 64% of the cases); (ii) loss of both the CD4 and CD8 antigens (11, 15% of the cases); (iii) coexpression of the CD4 and CD8 antigens (13, 17% of the cases); and (iv) expression of the CD1 antigen (eight, 11% of the cases). No correlation was seen between the occurrence of aberrant phenotypes and the histological subtype. It is concluded that the demonstration of an aberrant phenotype is a valuable supplement to histological assessment in the diagnosis of peripheral T cell lymphomas. It is recommended that the panel of monoclonal antibodies against T cell differentiation antigens should be fairly large, as apparently any antigen may be lost in the process of malignant transformation.

A case of a Ki-1 large cell anaplastic lymphoma with ultrastructural features

A 29-year-old woman first presented in 1982 with a large cell lymphoma, initially thought to be of histiocytic origin on the basis of prominent sinus infiltration. She had a complete response to chemotherapy, but relapsed in 1987. Histologically, a repeat biopsy was identical to the first. Immunocytochemically, there was strong reactivity with Ki-1 antibody and histiocyte lineage markers, but all specific T cell markers were negative. Southern blot hybridization demonstrated a clonally rearranged band with the T cell receptor (T beta) probe. Ultrastructurally, the cells showed sparse organelles except for prominent paranuclear Golgi apparatus, frequent reniform nuclear indentations, and ruffled cytoplasmic membranes. This case appears to represent a Ki-1-positive lymphoma with the hybrid features of an activated T lymphocyte and a histiocyte.

Relationship of histological subtypes to prognosis in early stage Hodgkin's disease: a review of 312 cases in a controlled clinical trial. The Groupe Pierre et Marie Curie

To assess the prognostic significance of a newer histologic classification of Hodgkin's disease (HD), microscope slides from the time of diagnosis of 312 clinical stage IA or B, IIA or B and IIIA patients were reviewed in 1987, 6-10 years after their participation in a radiochemotherapeutic trial (1976-1982). Overall, the diagnostic reproducibility of the Rye classification by the same pathologist was confirmed. However, a new analysis showed an improvement in the differential diagnosis between HD and non-Hodgkin's lymphomas (NHL) by the identification of 24 NHL (8%) amongst the patients originally diagnosed as HD. Most of the NHL identified on review had been classified originally as mixed cellularity. On review, none of the new histological subtypes of HD was significant for prognosis of relapse-free survival or overall survival. Only identification of NHL was shown to have an independent prognostic value on relapse rate (P = 0.012) and on overall survival (P = 0.10). It is concluded that diagnosis of HD by itself remains, in 1988, the sole histologic factor influencing the prognosis of these patients.

Peripheral T-cell lymphoma in childhood. A clinicopathological study of six cases

A review of the pathological material from 42 children with non-Hodgkin's lymphoma seen over a 44 month period revealed 10 large cell tumours. Of these, six were classified as peripheral T-cell lymphoma, an entity rarely reported in childhood. Three patients were boys and three girls (median age 9.5 years), and extranodal presentation was a feature of two patients. Five had high-grade tumours; of these, three were classified as large cell anaplastic, Ki-1 positive and two as pleomorphic large cell. The remaining patient had a low-grade tumour of angioimmunoblastic type. T-cell subsets were examined in three cases and showed the following phenotypes: CD4-, CD8-; CD4+, CD8-; CD4-, CD8+. Three of the patients with high-grade tumours died, with a mean survival of 22 weeks. The remaining patients are alive and clinically disease-free for between 10 and 24 months after treatment.

Bacterial lymphadenitis with the picture of a lymphoepithelioid cell lymphoma--Lennert's lymphoma

Three cases with the typical light microscopic picture of lymphoepithelioid cell lymphoma (so-called Lennert's lymphoma) were investigated by electron microscopy. Surprisingly, Lennert's lymphoma could be excluded in two cases. These two cases exhibited, in addition to pleomorphic lymphocytes and epithelioid cells, macrophages with accumulations of bacteria, indicating that a bacterial infection was the cause of the disease. By comparing the typical case of Lennert's lymphoma with the other cases, we found several criteria for distinguishing between Lennert's lymphoma and bacterial lymphadenitis. In bacterial lymphadenitis: (1) small and medium-sized lymphocytes exhibited a wide cytological spectrum whereas the lymphocytes in Lennert's lymphoma were relatively uniform; the lymphocytes with prominent lysosome-like granules found in Lennert's lymphoma were not seen; (2) cytology and distribution of epithelioid cells were similar to those in Lennert's lymphoma; (3) epithelioid venules contained recirculating lymphocytes, which were rarely found in Lennert's lymphoma; (4) numerous interdigitating reticulum cells, fibroblasts and myofibroblasts were seen, but not in Lennert's lymphoma; (5) focal increase in reticulin fibres was the main difference in light microscopy; (6) rod-shaped bacteria were accumulated in the cytoplasm of a few macrophages. The presence of bacteria could not be demonstrated unequivocally by light microscopy. In both cases the large number of intracytoplasmic bacteria suggests that this unusual and until now unknown lymphadenitis is the result of an infection caused by facultative intracellular parasitic bacteria. The outcome of bacterial lymphadenitis that gives the false impression of Lennert's lymphoma is uncertain. Cure was achieved in one of our cases. The other patient died before therapy was commenced.

Interdigitating cell sarcoma (ICS). Evidence of interdigitating cell origin, immunocytochemical studies with monoclonal anti-ICS antibodies

Three independent mouse monoclonal antibodies (mAbs) ID1 (IgG3), ID2 and ID3 (IgM) were raised against whole cells of a surgically resected human interdigitating cell sarcoma (ICS). In immunoperoxidase staining, these mAbs strongly stained the cytoplasm of ICS neoplastic cells as well as interdigitating cells in normal lymphoid tissues. These mAbs also detected monocyte/macrophages and dendritic cells, although their staining was highly variable depending on tissue distribution of the cells. Additional immuno-histological and enzyme histochemical study revealed that the neoplastic cells of ICS had cytoplasmic acid phosphatase and membranous alkaline phosphatase activity, and also possessed S100 beta protein, Ki-1 antigen. DAKO-macrophage antigen, and weak vimentin activity. Neither rearrangement of immunoglobulin heavy chain gene nor of T-cell receptor genes was detected in the DNA of ICS by Southern hybridization. These observations provide further confirmation of our previous finding (Nakamura et al. 1988, 1989) that the origin of ICS is interdigitating rather than lymphoid cell, and indicate that our mAbs could be useful as a cellular differentiation marker of interdigitating cells and for diagnosis of ICS.

A translocation involving a specific breakpoint (q35) on chromosome 5 is characteristic of anaplastic large cell lymphoma ('Ki-1 lymphoma')

Two cases of non-Hodgkin's lymphoma are reported in which a chromosomal translocation was observed involving the same site (q35) on the long arm of chromosome 5. The other breakpoint involved in the translocation was chromosome 2 (p23) in one case and chromosome 3 (q12) in the other. Both cases were large cell lymphomas expressing CD30 antigen ('Ki-1 lymphoma'). One was clearly of T lymphoid origin, the other probably B cell derived. One other case of a Ki-1 lymphoma with 2;5 translocation (involving the same breakpoint on chromosome 5) has been reported previously, and it is suggested that this cytogenetic abnormality may be specifically associated with Ki-1 lymphoma. The literature contains a further eight cases of lymphoid neoplasms with a translocation involving a breakpoint at q35 on chromosome 5. They have all been described as cases of 'malignant histiocytosis', but the present findings make it likely that these cases were in reality also examples of Ki-1 lymphoma. The breakpoint at the q35 region on chromosome 5 is close to the position of the fms proto-oncogene, suggesting that an abnormality affecting this gene might possibly play a causal role in 'Ki-1 lymphoma'. However, DNA restriction fragment analysis of the present cases showed no evidence that the breakpoint on chromosome 5 involves the fms gene or its immediate vicinity.

Detection of fos oncogene products by monoclonal antibody FO-120 in lymphoproliferative disorders

We investigated the expression of fos oncogene proteins in lymphoproliferative disorders, using a monoclonal antibody (FO-120) that was prepared against a synthetic oligopeptide of fos protein (amino acid sequence from 127 to 152). Although peripheral blood leukocytes were rarely positive for FO-120, they were transiently stained after lectin (PHA) stimulation. After culture with IL-2 for 1 or 2 weeks, less than 40% of the lymphocytes weakly reacted with FO-120, whereas strongly positive cells were detected in more than 70% of cells in half the T-cell lines established from preleukemic state of adult T-cell leukemia (pre-ATL) and all of ATL derived T-cell lines. All in vivo specimens of non-Hodgkin's malignant lymphomas, except for one case of T-cell lymphoma were also strongly positive. In addition, the extent of the antibody reactivity correlated with the histopathological grade of malignancy in B-cell lymphoma. The reactivity to most AILD-IBL lesions overlapped with that to T-lymphomas, and could be distinguished from that to reactive lesions. FO-120 appears to be a useful tool for detecting early neoplastic changes in lymphoproliferative disorders.

Histological and immunohistological analysis of human lymphomas

Morphological and immunological characteristics of lymphoproliferative diseases are reviewed. In particular, a basic distinction is made between non-Hodgkin's lymphomas and Hodgkin's disease. As to the non-Hodgkin's lymphomas, emphasis is given to the problems of classification, technical approach, histogenesis, and prognosis. The authors adopt a version of the Kiel Classification modified to take account of new knowledge regarding T-cell lymphomas. The value of immunophenotyping in making an accurate distinction between the various categories is stressed; immunocytochemical detection of the growth fraction is also discussed and then proposed as a new prognostic tool. Finally, the criteria for differential diagnosis between non-Hodgkin's lymphomas, malignant histiocytosis, non-lymphoid large cell tumors, and atypical immune reactions are outlined.

Ki-1 (CD30) antigen is released by Ki-1-positive tumor cells in vitro and in vivo. I. Partial characterization of soluble Ki-1 antigen and detection of the antigen in cell culture supernatants and in serum by an enzyme-linked immunosorbent assay

An enzyme-linked immunosorbent assay (ELISA) has been developed that allows the quantitative determination of the Ki-1 (CD30) antigen in soluble form. Similar levels of sensitivity of this new Ki-1 ELISA and the ELISA previously described for measuring the soluble 55-kDa chain of the interleukin 2 receptor were seen. As assessed with this ELISA, the investigated Ki-1+ permanent cell lines released the Ki-1 antigen into the culture supernatant. In culture supernatants of concanavalin A-activated human peripheral blood lymphocytes, however, this antigen could not be detected. The released Ki-1 antigen has an apparent molecular weight (Mr) of 85,000, whereas the cell-associated Ki-1 antigen has an Mr of 105,000. We investigated sera from 30 normal donors, 15 patients with systemic infections, and 63 patients suffering from lymphomas for soluble Ki-1 antigen. In all sera from normal donors and patients with systemic infectious diseases, soluble Ki-1 antigen was below the detection limit (i.e., less than 70 pg). In contrast, high amounts of the soluble Ki-1 antigen were found in sera from 18 malignant lymphomas containing Ki-1+ tumor cells. This finding demonstrates that the release of the Ki-1 antigen takes place not only in vitro, but in vivo as well. Moreover, these results imply that the Ki-1 antigen may be used as a serum tumor marker.

Malignant lymphomas of the nasal cavity and paranasal sinuses

The incidence of malignant lymphomas in the nasal cavity and paranasal sinuses was found to be 0.17% of all malignant lymphomas and 0.44% of all extranodal malignant lymphomas registered in the Kiel Lymph Node Registry from 1972 to 1987. Fifty-nine cases of malignant lymphoma presenting in the nasal cavity and paranasal sinuses were investigated with morphological and immunological methods. The median age of the patients was 64.5 years, with a female predominance (m:f = 0.87:1). In the 59 cases a marked preponderance of B-cell lymphomas was found (centroblastic n = 15, immunoblastic n = 8, Burkitt's lymphoma n = 6, Immunocytoma n = 3, centrocytic n = 1, centroblastic/centrocytic n = 1, plasmacytic n = 11); only a small number (n = 5) was of T-cell lineage (pleomorphic types). Nine further cases could not be assigned with certainty to either the T or B cell system. Angiocentricity with infiltration and destruction of vessel walls by tumour cells was demonstrated only in the T-cell lymphomas; the B-cell lymphomas, in contrast, often surrounded and compressed blood vessels with intact endothelium. No similarity to malignant lymphomas of mucosa associated lymphoid tissue, such as those in the gastrointestinal tract, was detected.

Pathology of Hodgkin's disease: anything new?

This presentation deals with the gross and microscopic pathology of HD. Recent advances in immunohistochemistry, gene rearrangement studies and cell culture are not discussed, except where they shed light on the pathology. Clinical and pathological experience, over the past 2 decades, suggests that HD should be divided into six subtypes, as originally proposed by Lukes et al. (1966b), rather than the four subtypes included in the Rye classification. Nodular lymphocyte/histiocyte predominant HD forms a clinicopathological entity separate from the other subtypes. It most frequently presents at a single nodal site and, even without therapy, progresses only slowly over a period of many years. A proportion of the patients (in the region of 10%) develop large cell NHL and a smaller number develop other types of Hodgkin's disease. This progression is not due to therapy since it most frequently occurs in untreated patients. Characteristic polylobated RS cell variants are seen in NLPHD. These differ from classic RS cells in that they have a B-cell phenotype, they do not show light chain restriction and, therefore, they do not appear to be a clonal proliferation. Although current dogma states that classic RS cells must be identified before a diagnosis of HD, including NLPHD, is made, it is the author's contention, supported by immunohistochemistry, that this type of RS cell does not occur in NLPHD. Polylobated RS cell variants in the appropriate cellular setting are, in themselves, diagnostic of NLPHD. They also serve to differentiate NLPHD from progressive transformation of germinal centres, an unusual proliferative expansion that may occur in association with HD but which, in itself, appears to be an entirely benign, reactive process. Diffuse lymphocyte/histiocyte predominant HD (DLPHD) differs from NLPHD in its diffuse growth pattern and the frequent presence of larger numbers of histiocytes. Polylobated RS cells are characteristic of both diseases. In some biopsies nodular and diffuse areas are seen in the same lymph node. Despite these similarities, the two diseases differ clinically (NLPHD is usually stage 1, DLPHD is frequently of a higher stage) and in their immunohistochemistry (fewer RS cell variants in DLPHD contain J-chain than in NLPHD). The reasons for these differences are not apparent and require further investigation. It may be due, at least in part, to the inclusion of cases of MCHD and NHL in the DLPHD category. Nodular sclerosis is the commonest category of HD in most reported series.(ABSTRACT TRUNCATED AT 400 WORDS)

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.

Angio-immunoblastic lymphadenopathy (AIL) or T-cell malignant lymphoma of AIL-type. A histopathological, immunohistochemical and ultrastructural study of 8 cases

Eight cases of AIL-type T-cell malignant lymphoma are reported. The clinical symptoms are the same as those described in AIL: fever, malaise, weight loss, skin rashes, polyadenopathy, and splenomegaly. However, some differences can be noted: the absence of hepatomegaly in all cases but one, the absence of polyclonal hypergammapathy in all cases but one, and predominance in females. The lymph node modifications comprise diffuse infiltrations of lymphoid cells with irregular nuclei and pale cytoplasm, associated with a large number of immunoblasts and plasma cells. Some eosinophilic granulocytes and epithelioid cells can be seen. Hyperplasia of the vessels and remnants of follicles, sometimes with proliferation of follicular dendritic cells, are prominent features. The immunolabelling study demonstrates the presence of an important T-cell population all expressing a high predominance of CD 4 phenotype. These findings are in accordance with those published in Europe and in contrast with those of some of the Japanese cases, particularly the first patients published by Shimoyama et al. The differential diagnosis with AIL is based on the presence of clusters of mainly large cells with a pale cytoplasm, on the loss of expression of one T cell marker, as in 3 cases of our series, and on the presence of a high percentage of lymphoid cells engaged in the mitotic cycle as demonstrated with the Ki 67 monoclonal antibody. However, to draw a clear cut difference between AIL-type T-cell lymphoma and AIL considered as a prelymphomatous dysimmune lymphadenopathy, only the demonstration of cytogenetic abnormalities, as in one of our cases or of rearrangement of the genes coding for beta and/or gamma chain of the antigen receptor of T-cell are valuable criteria. The follow-up of our series is not long enough to appreciate the prognosis. Three patients died, one from a glioma. All the other cases, treated with polychemotherapy show total remission with an evolution of 10 to 39 months.

Peripheral T-cell lymphoma

Since the discovery of human T-cell leukemia virus type 1 (HTLV-1) in patients with adult T-cell leukemia/lymphoma (ATLL), malignant neoplasms of mature (peripheral) T lymphocytes have attracted a great deal of attention. This type of neoplasm is more common in Japan than in Western countries, and may show distinct clinical pictures such as hypergammaglobulinemia, hypercalcemia, etc. T-cell lymphomas are more prone than B-cell lymphomas to become leukemic. Because of a marked intermingling of reactive cells (histiocytes, eosinophils, etc.), the histologic diagnosis of T-cell lymphoma is often difficult. Proliferation pattern and cellular size do not correlate with prognosis as in B-cell lymphoma. Since T-cell lymphomas often manifest with several distinct clinicopathologic settings, their categorization should be based on several parameters, such as the presence or absence of ATLL-associated antigen in serum, histology, phenotype of the neoplastic cell, and clinical features. Since a classification for T-cell lymphomas has not been established, a further multi-disciplinary approach is necessary for a better understanding of this interesting neoplasm.

Peripheral T cell lymphoma presenting primarily as lethal midline granuloma

This clinicopathologic study reports seven patients who primarily presented with ulcerative and destructive lesions of the upper aerodigestive tract and face, clinically consistent with so-called lethal midline granuloma (LMG). Histologically, the infiltrates were composed of atypical lymphoid cells that displayed angiocentricity and angiodestruction. In five patients, involvement of distant sites such as skin, lungs, lymph nodes, and bone marrow occurred, and in two cases, the disease remained localized. Immunomorphologic analysis, using monoclonal antibodies to frozen and paraffin sections, provided evidence for the diagnosis of peripheral T cell lymphoma (PTL) in all cases. The midline tumors were classified as diffuse mixed or diffuse large cell lymphoma occurred at distant sites. According to modern PTL classification systems, the lesions could be classified as pleomorphic T cell lymphomas. Those five patients who presented with or progressed to large cell lymphoma died within 18 months (mean, 7 months), whereas the two patients with localized disease are alive after 10 and 36 months, respectively. The size of the atypical lymphoid cells may be of prognostic significance since the large cell compartment seems to represent the major growth fraction in these PTLs.

Paraffin section immunohistochemistry. I. Non-Hodgkin's lymphoma

Reagents that recognize antigens on lymphoid cells in fixed and wax-embedded sections have been applied to a series of cases of non-Hodgkin's lymphomas. The panel consisted of MB1, 4KB5 (CD45r), LN1, L26 and MB2 which recognize antigens expressed predominantly on B-lymphocytes; UCHL1 and MT1 which recognize antigens expressed on T-lymphocytes and myeloid cells; antibodies recognizing the non-lineage antigens LeuM1 (CD15), BerH2 (CD30), anti-EMA; anti-lysozyme and MAC 387 which detect antigens present on some macrophages; and finally TAL1B5 (class II MHC), CAM 5.2 (low molecular weight cytokeratin) and PD7/26 + 2B11(CD45). Two hundred and four cases of non-Hodgkin's lymphoma have been studied, of which 158 had been fully characterized on frozen sections. The series was biased towards high-grade (n = 108) and T-cell (n = 44) tumours and these were largely prospectively accrued. It was found that discrimination between B-cell and T-cell lymphomas can be reliably achieved using these reagents and that a small panel (CD45, L26, MB2, MT1, UCHL1) is adequate for this purpose. Using the full range of reagents it is not possible to subdivide cases into groups that correspond with morphological subtypes of lymphoma. Although paraffin section immunohistochemistry is of value, the diagnosis of lymphoproliferative disorders must still be based upon the assessment of well fixed, carefully prepared tissue sections using conventional tinctorial methods.

Paraffin section immunohistochemistry. II. Hodgkin's disease and large cell anaplastic (Ki1) lymphoma

A panel of antibodies that recognize antigens that survive fixation and conventional processing have been applied to 43 cases of Hodgkin's disease and five cases of large cell anaplastic lymphoma. Reed-Sternberg cells in all five cases of nodular lymphocyte predominance Hodgkin's disease were positive with leucocyte common (CD45) and B-cell antibodies, and negative with LeuM1 (CD15) and BerH2 (CD30) antibodies. In other types of Hodgkin's disease, Reed-Sternberg cells were positive with BerH2 in all cases, positive with LeuM1 in 63% of cases (with enzymic predigestion), positive with at least one B-cell antibody in 29% of cases and positive for CD45 in 8% of cases. In 19% of all cases, Reed-Sternberg cells were positive for epithelial membrane antigen and in 93% they were positive with TAL1B5 (anti-class II MHC). No case showed immunoreactivity with anti-T-cell antibodies. The patterns of immunoreactivity of large cell anaplastic lymphoma were similar, except that none was positive with B-cell antibodies and three were positive with T-cell antibodies. All five were positive with BerH2 (CD30) and TAL1B5. Comparison of the results with those seen in other cases of non-Hodgkin's lymphoma indicates that, with the currently available reagents, this immunohistological profile cannot be used as the sole diagnostic discriminant of these conditions; this must still be based upon careful morphological assessment.

T-cell lymphoma: morphology, immunophenotype and clinical features

The histology, immunophenotype and clinical presentation of 43 cases of T-cell lymphoma are described. Cases were classified into nine types; T-lymphocytic lymphoma (three), mycosis fungoides (six), Sézary syndrome (two), T-zone lymphoma (13), angioimmunoblastic lymphadenopathy (AIL)-like T-cell lymphoma (five), pleomorphic medium cell (one), large cell immunoblastic (four), large cell polylobated (five) and lymphoblastic (four). The patients comprised 26 males and 17 females aged between 15 and 86 years. The majority showed disseminated disease at the time of diagnosis (18 stage IV, nine stage III, five stage II, eight stage I and three cases not staged). Thirty-one patients showed lymph node involvement. Cutaneous involvement was a common finding (18 cases, 10 cases excluding mycosis fungoides and Sézary syndrome). Details of therapy and clinical follow-up were obtained in 37 cases. With simple chemotherapy only one complete response (7%, 1/16) was obtained. With aggressive therapy 48% (13/27) of patients showed complete responses. Twenty patients died during the follow-up period. Life table analysis showed a 58% probability of surviving 1 year and 36% probability of surviving 3 years. There was a significant difference in survival probability between low/intermediate-grade (lymphocytic, Sézary syndrome, mycosis fungoides and T-zone lymphoma including AIL-type) lymphomas and high-grade (large cell immunoblastic and polylobated and lymphoblastic) lymphomas (P less than 0.025). However, when survival of T-zone and AIL-like T-cell lymphoma was compared with survival of large cell immunoblastic and polylobated lymphomas no significant difference was detected. Age (less than 50 years) and stage I or II disease were associated with significantly better survival (P less than 0.005 and P less than 0.05).

Characterization of the spectrum of postthymic T-cell malignancies in Taiwan. A clinicopathologic study of HTLV-1-positive and HTLV-1-negative cases

Postthymic T-cell malignancy shows marked geographic, clinicopathologic, and prognostic diversity. The frequency and spectrum of T-cell malignancies in Taiwan were investigated. Fifty-two patients (35 male and 17 female) with a median age of 49 years, were consecutively encountered between October 1983 and April 1987; these accounted for 39% of non-Hodgkin's lymphoma cases seen in our institutions. Ten patients (19.3%) had adult T-cell leukemia/lymphoma (ATL) associated with human T-cell leukemia virus (HTLV-1). Patients with ATL had disease similar to that reported from southwestern Japan and the Caribbean. They had frequent skin lesions (60%), hypercalcemia (40%), and a rapid clinical course with a median survival of 1.3 years. The 35 HTLV-1-negative peripheral T-cell lymphomas (PTL) were similar to PTL in western countries, manifesting frequent visceral, cutaneous, and vascular tropisms. Marrow involvement was documented at presentation in 39% and Stage III/IV disease in 80% of the PTL patients. The histology of PTL usually expressed prominent reactive features which is distinct from that in ATL. Several subcategories could be defined: Hodgkin's-like PTL in nine patients, T-zone lymphoma in three, angioimmunoblastic lymphadenopathy-like lymphoma in one, Lennert's lymphoma in three, and angioinvasive lymphoma in four. Two HTLV-1-negative PTL had neoplastic cells with clover-shaped nuclei and were designated as ATL-like. Morphologic classification based on the modified Working Formulation showed prognostic correlation, with median survival of less than 6 months for large cell/immunoblastic PTL, compared with 5 years for patients with small/medium cell PTL. Both low- and high-grade PTL seem to represent an incurable disease. Classical cutaneous T-cell lymphoma (seven cases) is relatively unusual in Taiwan, compared with the frequency of PTL. Post-thymic T-cell malignancies in Taiwan include HTLV-1-positive and HTLV-1-negative diseases, both of which have a poor prognosis and resemble similar T-cell malignancies in the East and West.

Primary cerebral T-cell lymphoma: a case report

A case of a 16-year-old boy with a rapidly progressive primary cerebral pleormorphic lymphoma of the brain is reported. Immunostaining with a panel of antibodies confirmed the T-cell lineage of the tumour. This is apparently the first documented report of primary T-cell lymphoma of the central nervous system.

Ultrastructural study of 4 cases of Ki-1 positive large anaplastic cell malignant lymphoma

The ultrastructural morphology of 4 cases of large anaplastic cell malignant lymphoma (Ana ML) is reported. Three cases were primary Ana ML and one pleomorphic large T cell lymphoma with some Ki-1 positive cells. All were confirmed by immunohistochemistry on frozen and paraffin sections. The Ki-1 and EMA positive tumour cells had an abundant cytoplasm, with no differentiation and large pale nuclei with multiple compact or dispersed nucleoli. The morphology is that of an activated cell engaged in protein synthesis and/or in the mitotic cycle. These tumour cells resemble to the Hodgkin's and monolobated Reed-Sternberg cells described in Hodgkin's disease.