Monoclonal antibodies reactive with normal and neoplastic T cells in paraffin sections

Granulocytic Sarcoma

Because of shared histologic and clinical features, granulocytic sarcoma (GS) may be confused with B- and T cell malignant lymphomas. Antibodies to myeloperoxidase, lysozyme, CD 15, and other determinants may correctly identify GS but are usually not part of the standard panels employed to evaluate a suspected non-Hodgkin's lym phoma. At the authors' institutions, these typically include reagents to CD20, CD43, CD45, CD45RO, and MB2. In this analysis, well-documented cases of GS and histologi cally similar lymphomas were assessed using a standard immunohistologic antibody panel employed in evaluation of putative lymphomas. In addition, antibodies to lyso zyme, myeloperoxidase, CD3, CD15, CD34, CD68, and MAC 387 were used in a second tier of analysis. The results were evaluated in a step-wise fashion. All B cell lymphomas and the majority of T cell cases were identified correctly by their reactivity for CD20 and CD45RO, respectively. Using the five standard lymphomas markers, 12 of 19 cases of GS had a phenotype that would be relatively unusual in non-Hodgkin's lymphoma—as reflected by CD43 and MB2 coexpression without CD20 or CD45RO-whereas 7 cases of GS showed a "CD43-only" phenotype and were there fore considered possible T cell lesions. All 19 GS cases were labeled by at least one second-tier marker and 18 exhibited two or more of these determinants at that level of evaluation. All T cell lymphomas failed to express CD 15, CD34, CD68, or MAC 387; however, 3 of 20 B cell tumors were focally positive for CD 15. CD3 labeled 9 of 11 cases of T cell lymphoma but also was seen in 11 of 16 cases of GS. These results indicate that, in suspected lymphoma cases, CD45-positivity, but failure to express CD20 or CD45RO, suggests the possibility of GS. Additional immunohistologic studies, in particular those for lysozyme or myeloperoxidase, can then be used to further define the tumoral lineage. Int J Surg Pathol 2(3):177-186, 1995

Lymphoma immunophenotyping: a new era in paraffin-section immunohistochemistry

Recent advances in immunohistochemistry have made it possible to investigate lymphomas for the expression of a wide range of antigens in fixed tissues. Epitope retrieval, sensitive detection methods, and the availability of new monoclonal antibodies have all contributed to one's ability to perform detailed immunophenotyping that previously could only be done in cryostat sections or by flow cytometry. Current lymphoma classifications make use of characteristic immunophenotypic profiles that aid in the reproducible diagnosis and subcassification of these neoplasms. The following is a review of the current state of immunophenotyping for lymphoid neoplasms in fixed tissues.

The role of MT2 and anti-bcl-2 protein antibodies in the differentiation of benign from malignant cutaneous infiltrates of B-lymphocytes with germinal center formation

MT2/CD45RA and anti-bcl-2 protein (Bcl-2) monoclonal antibodies are useful markers in distinguishing follicular lymphomas from reactive follicular hyperplasia of the lymph nodes. We examined biopsy specimens from 11 patients with primary cutaneous B-cell follicle center lymphomas, 10 patients with cutaneous pseudolymphomas with germinal centers, and 6 patients with inflammatory infiltrates with germinal centers in non-lymphoid cutaneous tumors (3 basal cell carcinomas, 2 malignant melanomas, and 1 solar keratosis), in order to evaluate the utility of MT2 and anti-Bcl-2 antibodies in differentiating benign from malignant germinal center cell proliferations in the skin. Immunohistochemical evaluation of MT2 and Bcl-2 was focused exclusively on the reactivity of germinal center cells. Specific membranous MT2 positivity was found in 2/11 cutaneous follicle center lymphomas; a diffuse, non-specific staining pattern was identified in 3/11 follicle center lymphomas and in 1/6 inflammatory infiltrates in non-lymphoid tumors. A negative MT2 reaction was observed in 6/11 follicle center cell lymphomas, in all cases of pseudolymphomas and in 5/6 inflammatory infiltrates in non-lymphoid tumors. Bcl-2 positivity was detected only in 1/11 follicle center lymphomas. Germinal center cells in all other cases were Bcl-2 negative. Our results suggest that MT2 and anti-Bcl-2 antibodies are only of limited value in differentiating primary cutaneous follicle center lymphomas from cutaneous pseudolymphomas with germinal centers.

Primary lymphoma of bone. Correlation of magnetic resonance imaging features with cytokine production by tumor cells

BACKGROUND

Primary lymphoma of bone is a rare, aggressive neoplasm that can present with a large, soft-tissue mass despite minimal evidence of cortical destruction on plain radiographs.

METHODS

High resolution magnetic resonance imaging (MRI) examinations of four patients with primary lymphoma of bone were reviewed retrospectively, and in each case intramedullary tumors demonstrated "penetrating channels" extending through the cortex. The MRI studies were correlated with the histopathologic assessment of the tumor for each patient. Immunohistochemistry was performed for immunophenotyping and for cytokine expression by tumor cells. The cytokines that were investigated were interleukin-1, interleukin-6, and tumor necrosis factor-alpha, molecules known to regulate osteoclastic activity.

RESULTS

The linear cortical foci noted on MRI correlated with the histopathologic findings of tumor-associated cutting cones, in proximity to osteoclastic bone resorption. Immunohistochemical stains showed a B-cell phenotype for each tumor and positive immunoreactivity in tumor cells for cytokine mediators that stimulate osteoclastic activation.

CONCLUSIONS

These findings indicate that the tumor cells in these cases produce soluble cytokine mediators that may regulate extensive osteoclastic activity. In primary lymphoma of bone, tumor activation of osteoclastic resorption, with production of tumor tunnels through the cortex, may represent one of the mechanisms by which lymphoma escapes the intramedullary space and forms large, soft-tissue masses without extensive cortical destruction.

Epstein-Barr virus-associated gastric lymphoma in Hong Kong Chinese

We report 11 cases of gastric lymphoma that harbor the Epstein-Barr virus (EBV) encoded small messenger RNA, EBER-1, detected by in situ hybridization. The cases represented 18% of 61 consecutive gastric lymphomas from three institutions in Hong Kong between 1988 and 1993. The mean age of patients was 62 years (range, 33 to 87). The male to female ratio was 5:6. Nine of the 11 (81.8%) EBER-1+ gastric lymphomas were diffuse large cell lymphomas of B-cell type without low grade components. Macroscopically these lymphomas appeared either as large noncleaved cell (centroblastic) or immunoblastic type. From the available follow-up data, five of the nine patients with B-cell lymphoma were alive and well 48, 40, 14, 13, and 12 months, respectively, after gastrectomy and chemotherapy. One patient died of postoperative pneumonia and one died of a second malignancy (esophageal squamous carcinoma) 40 months after gastrectomy. None of the EBER-1+ B-cell gastric lymphomas showed histological features characteristic of low grade lymphoma of the mucosa-associated lymphoid tissue (MALT) type reported to be common in some Western countries. Of the two patients with T-cell lymphoma, one had a pleomorphic T-cell lymphoma and the other had an angiocentric lymphoma. The former was lost to follow-up after the biopsy and the latter presented with gastric perforation and died 1.5 months after gastrectomy. It is concluded that a significant proportion of gastric lymphomas in Hong Kong Chinese are EBV-related and that they show histological features more akin to conventional node-based lymphomas than to MALT-type lymphomas.

Pathology with clinical correlations of primary central nervous system non-Hodgkin's lymphoma. The Massachusetts General Hospital experience 1958-1989

BACKGROUND

Primary central nervous system non-Hodgkin's lymphoma (NHL-CNS) is an enigmatic disease of uncertain origin. At the Massachusetts General Hospital, 104 patients with NHL-CNS were seen from 1958 through 1989. An impression of changes in the frequency of diagnosis, character of the tumors, and therapy for this disease prompted this study of the pathologic features, clinical data, and natural history of this tumor in these 104 patients.

METHODS

Histologic slides (neurosurgical specimens and autopsy tissues) were available for 99 patients. The tumors were classified by the Working Formulation classification. Immunostaining data and all clinical data were retrieved from the relevant offices and hospital charts.

RESULTS

Primary central nervous system non-Hodgkin's lymphoma tripled in frequency (5.66 cases per year in 1978-89 versus 1.75 cases per year in 1958-77) and now represents 6.6% of all primary brain neoplasms (versus 3.3% before 1978; chi 2 = 17.52, P < 0.01). For the 99 tumors histologically classified, 89% were high grade. Intermediate grade lymphomas, once the second most common subtype, have disappeared since 1983. All tumors had diffuse architecture; 77% (including all 11 patients with acquired immune deficiency syndrome) were large cell subtypes. Two cases were intravascular lymphoma. With one exception, all of the 41 tumors evaluated were B-cell types; 32 of 40 had monotypic surface immunoglobulin. There was 1 T-cell lymphoma. Of 64 tumor recurrences, 29 were at the initially defined site; 12 were in the leptomeninges, 29 were in other sites in the neuraxis, and 8 were in systemic sites. Systemic metastases have not occurred since 1984. Median survival for the 68 patients who survived after diagnostic surgery and for whom follow-up information could be obtained was 19 months; 9 months for those with high grade tumors and 30.5 months for those with intermediate grade tumors. This difference was not significant (P = 0.13). A separate set of seven patients had focal tumorlike lymphoid infiltrates composed of benign-appearing lymphocytes, which were associated with good long term survival. The differential histologic diagnosis of NHL-CNS was occasionally difficult, and the spectrum of this differential was broader than generally stated.

CONCLUSIONS

Primary central nervous system non-Hodgkin's lymphoma has increased in frequency even in nonimunocompromised patient populations. This increase has been accompanied by the disappearance of intermediate grade histologic types, suggesting a fundamental shift in the biology of the neoplasms. The introduction of chemotherapeutic regimens appears to have altered the natural history such that systemic metastases outside the central nervous system no longer occur, and there are now some long term survivors of this formerly uniformly fatal disease.

Distinction of follicular hyperplasia from follicular lymphoma in B5-fixed tissues: comparison of MT2 and bcl-2 antibodies

The distinction between follicular hyperplasia (FH) and follicular lymphoma (FL) is one of the classic problems in diagnostic hematopathology. Both MT2 and bcl-2 antibodies have been reported to be useful in making this distinction. To compare the utility of these two commercially obtained antibodies in paraffin-embedded sections, B5-fixed sections from 21 cases of follicular hyperplasia and from 46 follicular lymphomas were immunostained and the follicles evaluated. Neither MT2 nor the bcl-2 antibody showed definite follicular positivity in FH. In contrast, 66% of FLs were MT2 positive and 89% were bcl-2 positive (P < .02). MT2 staining was equivocal in 30% of FHs and 7% of FLs, whereas bcl-2 staining was equivocal in only one FL. In addition, MT2 staining was unsatisfactory in three cases. CD10 was negative (0% to 3%) in the three bcl-2-negative FLs tested and positive (> 10%) in 26 of 38 bcl-2-positive cases. These results demonstrate the utility of the commercially obtained bcl-2 antibody in distinguishing FL from FH in B5-fixed, paraffin-embedded tissue sections. They also illustrate the superiority of the bcl-2 antibody over MT2, which was less sensitive and more problematic to interpret.

Primary T-cell immunoblastic lymphoma of the orbit in a pediatric patient

BACKGROUND

The authors report a case of an 8-year-old pediatric patient with a 2-week history of painless periorbital swelling unresponsive to antibiotic treatment.

METHODS

Computed tomography (CT) showed a large, lateral, anterior left orbital soft tissue mass with bony erosion into the anterior cranial fossa through the roof of the orbit laterally. Surgical exploration showed a hard white mass that had eroded through the roof of the left orbit and into the anterior cranial fossa, with herniation of the brain and associated dura through the defect. Results of a complete evaluation of the child for systemic lymphoma, including a lumbar puncture, chest x-ray, bone scan, bone marrow aspirate, and chest/abdomen CT, were negative.

RESULTS

Results of histopathologic and immuno-histochemical evaluation showed a primary orbital T-cell immunoblastic lymphoma. The patient was treated with intrathecal ara-C (Cytosar-U) and methotrexate, 16.2 Gy of whole brain irradiation, and a chemotherapeutic protocol consisting of cyclophosphamide (Cytoxin), vincristine (Oncovin), methotrexate, daunomycin, and prednisone. The patient remains free of lymphoma 33 months after diagnosis, with 20/20 visual acuity in both eyes.

CONCLUSION

The authors believe that this is the youngest documented case of a primary T-cell immunoblastic lymphoma of the orbit.

Immunohistochemical analysis of small cell tumors of the thyroid gland: an Eastern Cooperative Oncology Group study

The majority of small cell anaplastic tumors of the thyroid gland are generally believed to be non-Hodgkin's lymphomas, including most of those formerly classified as small cell carcinomas. Using a panel of antibodies capable of detecting epithelial, neuroendocrine, and B and T cells in paraffin-embedded tissue sections, we studied 68 thyroid neoplasms in which the original diagnosis was small cell carcinoma or lymphoma. Sixty-three of the tumors were identified as lymphomas of B-cell origin on the basis of L26 reactivity used in conjunction with light chain restriction and MB2 immunostaining. Two additional tumors were classified as lymphomas of indeterminate phenotype. Immunophenotyping indicated an epithelial origin in the remaining three tumors. No cases of medullary carcinoma were detected by immunostaining. Histologic review revealed a predominance of large cell and immunoblastic lymphomas, with low-grade lymphomas of mucosa-associated lymphoid tissue histology accounting for only five cases. Our findings indicate that the majority of small cell anaplastic tumors of the thyroid are B-cell lymphomas. Although primary small cell carcinoma of the thyroid may rarely occur, this diagnosis should not be made without immunohistologic confirmation.

CD43 expression in B cell lymphoma

AIMS

To determine the expression of CD43 in frozen sections in a range of B cell lymphomas.

METHODS

The monoclonal antibody WR14, clustered provisionally in the Fourth Leucocyte Typing Workshop as a CD43 reagent, was investigated by epitope blocking studies on formalin fixed reactive lymph node tissue, using the established CD43 antibody MT1, to validate its use as a CD43 reagent. CD43 expression was studied in 131 immunophenotypically defined B cell lymphomas, including lymphocytic lymphoma (Lc, n = 13), centrocytic lymphoma (Cc, n = 14), and a range of follicle centre cell lymphomas (FCC) including centroblastic/centrocytic follicular (CbCcF, n = 48), centroblastic diffuse (CbD, n = 39), centroblastic/centrocytic diffuse (CbCcD, n = 4), centroblastic follicular and diffuse (Cb FD, n = 3) and centroblastic/centrocytic follicular and diffuse (CbCc FD, n = 1). Nine lymphomas of mucosa associated lymphoid tissue (MALT) were also examined.

RESULTS

Epitope blocking studies showed that WR14 is a CD43 reagent that binds to an epitope identical with or close to that recognised by MT1. Eleven of 13 (84%) cases of Lc and 11 of 14 (78%) cases of Cc expressed CD43; 87 of 95 (91%) cases of FCC did not. All eight low grade lymphomas of MALT were negative. One high grade lymphoma, transformed from a low grade MALT lymphoma, was positive for CD43. The expression of CD43 by tumours of B cell lineage was associated with the expression of CD5 (p < 0.001) although either antigen could occasionally be found in the absence of the other.

CONCLUSION

CD43 reagents can be used in conjunction with CD5 antibodies for the immunophenotypic discrimination of follicle centre cell lymphomas from non-follicle centre cell lymphomas.

Using Kryofix as alternative for formalin results in more optimal and standardized immunostaining of paraffin sections

Although used for over one century formalin has several disadvantages which Kryofix, an alternative fixative for paraffin blocks used in Leiden for 6 years, does not have. In this study the effects of Kryofix on tissue regarding immunohistochemistry are compared with those of buffered formalin. All markers studied showed enhanced staining in the Kryofix blocks after 4 hours of fixation, whilst in some cases the immunostaining of the formalin blocks was even negative. For all markers, the sera could be further diluted for the Kryofix sections, for some with as much as a factor 20, enhancing the cost-effectiveness of the method. We established that for formalin, the fixation time strongly influenced the results. For Kryofix there was no time factor: the immunostaining results of 1 hour fixation were identical to those after 3 months of fixation. This study shows that by this method of fixation, in which there is no cross-linking of proteins, immunostaining of paraffin sections is optimized and standardized.

The distribution and possible function of gamma interferon-immunoreactive cells in normal endometrium and myometrium

T-lymphocytes are present in normal endometrium, where they may have a role in the control of glandular maturation. T-cell activity could be related to the local secretion of cytokines such as gamma interferon, which has an anti-proliferative effect on endometrial epithelial cells in vitro. We have examined gamma interferon immunoreactivity and T-cell distribution in 24 normal pre-menopausal uteri. Endometrial appearances were representative of all stages of the menstrual cycle. Most cells in the lymphoid aggregates in the stratum basalis were stained by T-cell and gamma interferon antisera. T-lymphocytes were also scattered in glandular epithelium and throughout the stroma of basal and functional layers; immunoreactivity for gamma interferon was less consistent in these cells. There was no alteration in the intensity or distribution of gamma interferon staining in different phases of the menstrual cycle. Endometrial granulocytes (K-cells) present mainly in the late secretory endometria were not reactive with the gamma interferon antiserum. In addition to endometrial staining, T-cells were distributed in all areas of the myometrium in most uteri, and many myometrial lymphocytes were gamma interferon positive. These results support a role for gamma interferon in endometrial physiology, possibly as an inhibitor of epithelial proliferation.

Monoclonal antibody OPD4 detects neoplastic T cells but does not distinguish between CD4 and CD8 neoplastic T cells in paraffin tissue sections

Monoclonal antibody (MoAb) OPD4, reported to preferentially react with benign CD4 T cells in formalin-fixed tissue sections, was examined for its reactivity with 56 T-cell neoplasms after formalin or Bouin's fixation to determine if it also preferentially detects neoplastic CD4 T cells in paraffin tissue sections. Monoclonal antibody OPD4 did not preferentially detect neoplastic CD4 T cells, since it reacted with 22 of 38 (58%) CD4-positive compared with nine of 14 (64%) CD4-negative T-cell neoplasms. However, MoAb OPD4 appears to detect neoplastic T cells in Bouin's-fixed (11 of 20 cases [55%]) about as well as in formalin-fixed (20 of 32 cases [63%]) tissues. Since MoAb OPD4 does not preferentially react with neoplastic CD4 T cells, the utility of this MoAb as a pan-T-cell marker in routinely processed tissues was also explored and compared with that of Leu-22, UCHL-1, and CD3. All four antibodies reacted with approximately the same percentage of T-cell malignancies (51% to 57%). However, examination of different clinicopathologic groups and types of fixative highlighted differences. Monoclonal antibodies OPD4 and Leu-22 reacted with 62%, while CD3 detected only 41% of formalin-fixed, postthymic T-cell neoplasms. OPD4, UCHL-1, and CD3 each reacted with 55%, but Leu-22 recognized only 45% of Bouin's-fixed, postthymic T-cell malignancies. OPD4 reacted with none, but CD3 reacted with all four T-cell lymphoblastic lymphomas. Various antibody combinations were examined to determine an optimal panel for the recognition of T-cell neoplasms in paraffin sections. The combination of MoAbs OPD4 and Leu-22 detected 86% of postthymic T-cell neoplasms in formalin-fixed tissue sections. Furthermore, MoAb OPD4 appears to be relatively specific for T-cell neoplasms, detecting 31 of 56 (55%) T-cell malignancies, while only reacting with two of 39 (5%) B-cell neoplasms. Therefore, while not preferentially reactive with neoplastic CD4 T cells, MoAb OPD4 may be useful as a pan-T-cell marker of postthymic T-cell neoplasms in routinely processed, formalin-fixed tissues, especially when used in conjunction with MoAb Leu-22.

Characterization of the inflammatory infiltrate in ovarian dysgerminoma: an immunocytochemical study

The inflammatory infiltrate has been characterized in 10 cases of ovarian dysgerminoma using a panel of antisera to T-cells, B-cells and macrophages. The expression of Class II major histocompatibility complex (MHC) antigens and the distribution of interferons alpha and gamma were also examined. T-lymphocytes were present in all tumours, often closely admixed with neoplastic elements. T-cells in most areas were immunoreactive with gamma interferon. B-cells were generally scanty although germinal centres were present in three tumours. Immunocytochemistry revealed greater numbers of macrophages than had been appreciated on routinely stained sections. Macrophages were closely related to both lymphoid and tumour cells, and many macrophages were immunoreactive for alpha interferon. Class II MHC expression was mainly restricted to macrophages and B-cell areas although occasional T-cells were also stained. Dysgerminoma cells did not express Class II MHC antigens.

Extranodal oral lymphomas: histologic subtypes and immunophenotypes (in routinely processed tissue)

Twenty-seven extranodal oral lymphomas were subclassified according to the National Institutes of Health International Working Formulation. Immunophenotypes were then determined by means of an ABC technique with newly generated antibodies that identify fixation-resistant antigens on lymphoid cells. Diffuse small and large cell lymphomas were the most frequently identified subtypes. B-cell-associated antibody, L26, stained a majority of tumor cells in all lymphomas. Although 4KB5 was a less consistent B-cell marker, it stained most lymphomas. Reactive T-cell infiltrates, identified with antibodies MT1, UCHL-1, anti-CD3, and OPD4, varied from slight to intense. MT1 occasionally showed cross-reactivity with neoplastic B cells. No "histiocytic" lymphomas were found, but reactive macrophage infiltrates were identified in many lymphomas with monoclonal antibody KP1. In view of the immunohistochemical results, all lymphomas were believed to be of B-cell origin. Although antibody panels of the type used in this study can be effective in subtyping routinely processed oral lymphomas, careful interpretation is required because of reactive T-cell infiltrates.

Use of monoclonal antibodies for the typing of malignant lymphomas in routinely processed biopsy samples

Eight antibodies (UCHL1 (CD45RO), MT1 (CD43), MT2 (CD45R), 4KB5 (CD45R), MB1 (CD45R), MB2, L26 (CD20) and LN1 (CDw75)) have been examined for reactivity with routine specimens of normal and hyperplastic lymphoid organs (n = 6), non-Hodgkin's lymphomas (n = 62), Hodgkin's disease (n = 27) and non-lymphoid malignancies (n = 9). In normal and hyperplastic lymphoid organs, UCHL1 and MT1 stained predominantly T cells; 4KB5, MB1, MB2, L26 and LN1 stained predominantly B cells; and MT2 reacted with a subset of B and T cells. The lineage of the neoplastic cells was correctly identified in 24 of 28 (86%) peripheral T-cell lymphomas; and in 31 of 35 (88%) B-cell malignancies. In two cases of lymphocyte-predominant Hodgkin's disease, the Hodgkin's and Reed-Sternberg (H&RS) cells were 4KB5+, L26+ and/or LN1+. The H&Rs cells in nodular sclerosis and mixed cellularity Hodgkin's disease were positive with 4KB5 in 17 of 25 cases. Antibodies UCHL1, MT1, MB1, MB2, L26 and LN1 also labelled some H&RS cells, but in a much smaller proportion of the cases. In three of nine non-lymphoid neoplasms, UCHL1 and MB2 showed a staining of the neoplastic cells, but the staining was cytoplasmic rather than membrane-associated. The remaining antibodies were unreactive with the non-lymphoid malignancies. It is concluded that many non-Hodgkin's lymphomas can be typed in routine specimens, and that antibodies UCHL1, MT1, L26 and LN1 are especially useful in this respect. The antibodies do not provide a means of distinguishing between non-Hodgkin's lymphomas and Hodgkin's disease.

Histologic and immunohistologic diversity of non-Hodgkin's lymphoma of lymph node origin

To examine whether nodal non-Hodgkin's lymphomas (NHL) share common features in every nodal site, histologic and immunohistologic findings were analyzed site by site. Cases selected were nodal NHL of neck (17 cases), submandibular (10 cases), inguinal (9 cases), and abdominal cavity (22 cases). No significant differences in age distribution were found. A slight female preponderance was present in cases with inguinal NHL. Histologic and immunohistologic findings showed that nodal NHL were heterogeneous; (1) T-cell type was frequent in the neck but exceptional in other sites, (2) frequency of high-grade tumors was much higher in the intra-abdominal cavity but low in other sites, and (3) follicular lymphoma was common in the submandibular and inguinal regions. Previous studies indicated that histologic and/or immunologic types of NHL correlated with pathogenesis of lymphoma; EB virus and HTLV-1 for B and T lymphomagenesis, respectively, and acquired immunodeficiency syndrome (AIDS) for development of high-grade tumors. The present results may provide an insight to consider as a possible pathogenesis of NHL.

Peripheral T-cell lymphomas: a clinicopathologic study of 75 cases

Seventy-five peripheral T-cell lymphomas (PTLs) were classified according to the recently proposed "Updated Kiel Classification of Non-Hodgkin's Lymphomas" (mycosis fungoides and Sezary's syndrome excluded). Thirty-seven PTLs belonged to the low-grade category (T-cell chronic lymphocytic leukemia [T-CLL], 3; lymphoepithelioid, 4; angioimmunoblastic, 22; T-zone, 6; pleomorphic small cell, 2) and 38 belonged to the high-grade category (pleomorphic medium and large cell, 24; immunoblastic, 1; large-cell anaplastic Ki-1-positive, 13). Loss of pan-T antigens occurred exclusively in high-grade PTLs; on paraffin sections UCHL 1 was slightly more sensitive than MT 1. Sixty patients presented with lymphadenopathy and 15 patients (20%) presented with extranodal disease most frequently affecting the skin and upper aerodigestive tract. B-cell lymphoma symptoms were found in 43 cases (57%) and bone marrow involvement (T-CLL excluded) was found in 12 cases (17%). Staging (T-CLL excluded) revealed stage I in 13%, stage II in 15%, and stages III and IV in 72% of the cases. Among the intensively treated patients, 37% achieved complete remission and 15 are still in complete remission after 4 to 79 months (median: 24 months). The overall median survival (MS) rate was 23 months. Peripheral T-cell lymphoma of pleomorphic medium and large-cell type was the most aggressive lymphoma (MS: 8 months). B-cell lymphoma symptoms, bone marrow involvement, and Ki-67 positivity 60% or greater significantly shortened survival times, whereas age (under 60 versus over 60 years), stage (I and II versus III and IV), and grade had no significant influence. Ki-67 reactivity was found to be a prognostic factor which allows prediction of probable poor outcome, especially in cases with limited stage of disease.

Immunoblastic T-cell lymphoma presenting as an eyelid tumor

A 59-year-old white man presented with an ulcerating mass of the left upper eyelid of 6 months' duration. A biopsy specimen of the tumor was diagnosed as an immunoblastic T-cell malignant lymphoma. The lesion completely regressed after 4000 cGy of cobalt-60 radiation therapy. In the ensuing 33 months, multiple, widespread skin nodules of the same neoplasm developed including a right upper eyelid tumor. To the authors' knowledge, this is the first reported case of an immunoblastic T-cell lymphoma initially manifesting as an eyelid neoplasm.

Malignant lymphomas of bone in Japan

Thirty-four cases of primary non-Hodgkin's lymphoma (NHL) of bone collected from hospitals in Japan were histologically and immunohistologically reviewed, and the results were compared with those in Western countries. There were no remarkable differences in age, sex, and the distribution of bone tumors between Japanese and Western cases. Sixteen cases (47%) diagnosed previously as "reticulum cell sarcoma" were reclassified as diffuse NHL of large cell (seven cases), mixed type (four cases), immunoblastic type (three cases), clear cell type (one case), and multilobated type (one case). The cases with small lymphocytic type with plasmacytoid features (lymphoplasmacytic type) were more common in Japan (35% of our cases) than in Western countries. The distribution of histologic subtypes, except for lymphoplasmacytic and T-cell lymphomas, in the current cases was similar to that in Western countries. However, immunohistochemistry showed that Japanese cases contained a much higher frequency of T-cell lymphoma (10% of all cases) than Western cases. Histologic grade according to the Working Formulation correlated well with clinical stage. There may be a tendency towards better prognosis with lower grade tumors, but this was not statistically significant.

Molecule detected in formalin fixed tissue by antibodies MT1, DF-T1, and L60 (Leu-22) corresponds to CD43 antigen

Three monoclonal antibodies MT1, L60 (Leu-22), and DF-T1, were reported independently as recognising human T cells in routinely processed, paraffin wax embedded tissue. The present study was performed to compare these three reagents in terms of their immunocytochemical reactions and target molecule(s). On Western blotting of white cell extracts the three antibodies reacted with antigens of the same molecular weight (range 110-160 kilodaltons). Furthermore, their immunocytochemical reactivity with normal human cells, as analysed by two-colour flow cytometry, was essentially identical (labelling of monocytes, most T lymphocytes, and weak reactions with some B cells), and the antibodies gave closely similar reactions on 54 white cell derived neoplasms. To identify the target antigen for these three reagents, antibodies from the Third International Workshop on Leucocyte Antigens were reviewed and it was shown that the Western blotting and immunocytochemical reactions of MT1, L60 (Leu-22), and DF-T1 were identical with those of the reagents which defined the CD43 antigen (also known as leucosialin or sialophorin). Furthermore, all these antibodies reacted with cells transfected with a cDNA clone encoding CD43. It is concluded that antibodies MT1, L60 (Leu-22), and DF-T1 all recognise the heavily glycosylated myeloid/lymphoid associated CD43 antigen.

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.

Immunophenotypic analysis of sinonasal non-Hodgkin's lymphomas

A panel of paraffin effective antibodies recognizing B cells and T cells (LN-2, MB1, L26, MT1, UCHL1, kappa, lambda) was used to characterize the immunophenotypes of 26 sinonasal non-Hodgkin's lymphomas. Seventeen tumors were stage I, five were stage II, one was stage III, and three were stage IV. Nine lymphomas were classified morphologically as large cell, six were large cell immunoblastic, six were small cleaved cell, two were mixed small and large cell, two were small noncleaved cell, and one was lymphoblastic. None were follicular. Twenty-two lymphomas had a B cell immunophenotype, three were T cell neoplasms, and one was immunoreactive only for MT1. This predominance of sinonasal lymphomas with a B cell immunophenotype in patients residing in the United States contrasts with the almost exclusive occurrence of T cell sinonasal lymphomas in Chinese patients living in Hong Kong and Japanese patients residing in regions of Japan that are nonendemic for human T cell leukemia virus-1.

A fatal case of multicentric Kikuchi's histiocytic necrotizing lymphadenitis

Kikuchi's histiocytic necrotizing lymphadenitis (Kikuchi's disease) is a histologically alarming but self-limiting lesion typically affecting the cervical lymph nodes of young adults. The authors report the first case of fatality occurring during the active phase of Kikuchi's disease. The 38-year-old patient presented with fever and generalized lymphadenopathy. During hospitalization, he developed abrupt onset of heart failure and died. Postmortem examination revealed enlarged lymph nodes all over the body showing typical histologic changes of Kikuchi's disease, but there was no encroachment on vital structures. The heart was dilated and flabby, with multiple microscopic foci of necrosis and mild fatty change. There were no other significant findings, and all cultures were negative. The authors speculate that large amounts of cytokines produced by the histiocytes or high endogenous catecholamines resulting from the stress response might be responsible for the myocardial damage. Alternatively, infection by an as yet uncharacterized microbial might be the underlying cause for both the lymphadenitis and myocardial disease.

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.