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

Cd30-Positive Cutaneous Anaplastic Large Cell Lymphoma with Ichthyosis Acquisita

Anaplastic large cell lymphoma (ALCL) is a high-grade non-Hodgkin's lymphoma recognized by the expression of the CD30 marker and by its morphology. We report an unusual case of ALCL in a 42-year-old woman. For ten years the patient only had pruritic erythematous skin lesions, then a plaque with nodules and ulcers on the right thigh and leg developed, followed by ichthyosis acquisita. The development of ALCL in women and the association of ichthyosis acquisita with this type of lymphoma are uncommon.

T-cell lymphomas, a challenging disease: types, treatments, and future

T-cell lymphomas are rare and aggressive malignancies associated with poor outcome, often because of the development of resistance in the lymphoma against chemotherapy as well as intolerance in patients to the established and toxic chemotherapy regimens. In this review article, we discuss the epidemiology, pathophysiology, current standard of care, and future treatments of common types of T-cell lymphomas, including adult T-cell leukemia/lymphoma, angioimmunoblastic T-cell lymphoma, anaplastic large-cell lymphoma, aggressive NK/T-cell lymphoma, and cutaneous T-cell lymphoma.

Adverse prognostic significance of CD20 positive Reed-Sternberg cells in classical Hodgkin's disease*

The prognostic significance of CD20 positive classical Hodgkin's disease (cHD) is uncertain. All cHD cases referred to the Memorial Sloan-Kettering Cancer Center (MSKCC) were retrospectively identified (5/92-11/00); the samples were immunostained, and clinical data ascertained. Cases were re-reviewed without knowledge of clinical outcome. Univariate and multivariate analyses were performed 248 patients had cHD: 28 CD20(+) (11%); 220 CD20(-). All clinical characteristics were comparable except haemoglobin level at presentation. With a median follow-up of 29.2 months, significant prognostic factors in multivariate analysis were: CD20 positivity, elevated white blood cell count (WBC) and low absolute lymphocyte count for time-to treatment failure (TTF); and for overall survival (OS), CD20 positivity, elevated WBC count, bone marrow involvement and age >/=45 years. TTF was significantly poorer for ABVD-treated patients with CD20(+) cHD as compared with CD20(-) cHD. Among 167 patients treated at MSKCC, both TTF (P < 0.0001) and OS (P = 0.017) were significantly decreased in CD20(+) patients as compared with CD20(-) cHD. CD20(+) cHD is a poor prognostic factor for TTF and OS. All cHD cases should be immunophenotyped for CD20. A large prospective trial is needed to confirm these findings.

Molecular biology of anaplastic lymphoma kinase-positive anaplastic large-cell lymphoma

Anaplastic large-cell lymphoma (ALCL) provides an excellent example of how molecular insights into tumor pathogenesis are influencing and improving tumor classification. ALCL was described initially as a subtype of T-cell/null-cell lymphoma characterized by unusual tumor cell morphology and the expression of CD30. However, it was soon recognized that a subset of ALCLs contained chromosomal translocations involving anaplastic lymphoma kinase (ALK), a novel receptor tyrosine kinase gene. These rearrangements create chimeric genes encoding self-associating, constitutively active ALK fusion proteins that activate a number of downstream effectors, including phospholipase C-gamma, phosphoinositol 3'-kinase, RAS, and signal transducer and activator of transcription proteins, all of which seem potentially important in cellular transformation. Not all tumors classified as ALCLs have ALK rearrangements and, conversely, ALK rearrangements occur in lymphomas of widely varying morphology. Hence, only molecular markers can reliably identify ALK+ ALCL. The importance of doing so is reflected by clinical studies suggesting that ALK+ ALCLs have a significantly better prognosis than other aggressive peripheral T-cell or B-cell lymphomas, including ALK- ALCLs. The unique molecular pathogenesis of ALK+ ALCL is likely to lead to novel therapeutic approaches directed at specific inhibition of ALK or downstream effectors.

T-cell/histiocyte-rich large B-cell lymphoma is a disseminated aggressive neoplasm: differential diagnosis from Hodgkin's lymphoma

AIMS

An accurate diagnosis of T-cell/histiocyte-rich large B-cell lymphoma needs to take into consideration those forms of Hodgkin's lymphoma also characterized by a predominance of small lymphocytes and histiocytes, i.e. nodular lymphocyte predominance Hodgkin's lymphoma and lymphocyte-rich classical Hodgkin's lymphoma. We have studied the clinical, phenotypic and genetic features of a series of 12 cases of T-cell/histiocyte-rich large B-cell lymphoma along with 18 cases of Hodgkin's lymphoma for comparative purposes.

METHODS AND RESULTS

Of the Hodgkin's lymphoma cases, there were 11 lymphocyte predominance type and seven classic type. T-cell/histiocyte-rich large B-cell lymphomas presented usually in advanced stages (III or IV in 11/12 cases), frequently with 'B' symptoms (6/9 cases), and followed a more aggressive course than Hodgkin's lymphoma (4/8 patients died due to the tumour in T-cell/histiocyte-rich large B-cell lymphoma versus 0/15 in Hodgkin's lymphoma). T-cell/histiocyte-rich large B-cell lymphoma cases showed diffuse effacement of the nodal architecture by a proliferation of scattered large atypical B-cells obscured by a background of small T-lymphocytes (more CD8+, TIA1+ than CD57+). Five cases showed also a prominent histiocytic component. The large B-cells expressed CD45 and often EMA (6/10 cases). On the other hand, CD 30, CD15 and latent infection by Epstein-Barr virus (EBV) were generally lacking. bc l6 and CD10 were, respectively, detected in 6/6 and 1/5 cases. Conventional polymerase chain reaction (PCR) showed monoclonal immunoglobulin heavy chain (IgH) gene rearrangements in all T-cell/histiocyte-rich large B-cell lymphomas studied (5/5), but did not detect any case with t(14;18) involving the major breakpoint region (0/4).

CONCLUSIONS

The differential diagnosis of T-cell/histiocyte-rich large B-cell lymphoma from Hodgkin's lymphoma is facilitated by the integration of different immunophenotypic, molecular and clinical findings. T-cell/histiocyte-rich large B-cell lymphoma is a monoclonal neoplasm of bc l6+ B-cells with a phenotypic profile similar to lymphocyte predominance Hodgkin's lymphoma, suggesting a germinal centre origin and a possible relation to this disease. Therefore, in order to distinguish it from lymphocyte predominance Hodgkin's lymphoma, characterization of the reactive background, IgH gene rearrangement studies by conventional PCR and clinical features are more useful. In contrast, T-cell/histiocyte-rich large B-cell lymphoma can be distinguished from classical Hodgkin's lymphoma thanks to the presence of monoclonal IgH rearrangement and the CD 30-CD15-CD45+EMA+ immunophenotypic profile of the neoplastic cells in T-cell/histiocyte-rich large B-cell lymphoma.

Immunophenotypic analysis of simultaneous specimens from different sites from the same patient with malignant lymphoma

Immunophenotypic analysis of simultaneous specimens from different sites from the same patient with malignant lymphoma The assumption that immunophenotypic characteristics of different specimens obtained simultaneously from the same patient remain unchanged has rarely been evaluated. Using flow cytometry, we reviewed our experience of 29 patients with non Hodgkin's lymphoma (NHL). From these patients, 60 simultaneous specimens taken from the peripheral blood, bone marrow, effusions, fine needle aspirates from lymph nodes or cerebrospinal fluid were studied. In 26 out of 29 patients, the immunophenotype in the different specimens was identical. In one patient with unclassifiable low-grade B-NHL, immunophenotyping showed additionally a CD38 expression in the effusion which was not seen in the bone marrow. In one patient with mantle cell lymphoma, expression of CD10 in the lymph node was noted which was lacking in the peripheral blood. In the remaining patient with unclassifiable low-grade B-NHL, CD23 expression was noted in the lymph node but not in the peripheral blood. This retrospective study suggests that discordant antigen expression in samples from different body sites within the same patient is a rare event.

Malignant mesothelioma with CD30-positivity. A case report and review of the literature

The activation marker CD3O is useful in the diagnosis of Hodgkin and non-Hodgkin lymphomas. It has also been described in nonhematopoietic tumors, including pancreatic carcinomas, salivary gland tumors, and embryonal carcinomas. We report a case of malignant mesothelioma with intense CD30 positivity. This finding has not previously been described and is important in broadening the differential diagnosis of a CD30(+) cohesive large cell malignancy.

Paraffin immunohistochemistry as an adjunct to hematopathology

In the past two decades, there have been a number of dramatic advances in immunology that have subsequently affected immunohistochemistry. These have had a substantial impact on all phases of laboratory medicine, especially surgical pathology. Many hospital laboratories use immunohistochemical analysis on paraffin-embedded tissue sections as routinely as other special histochemical techniques. Hematopathology, in particular, has become increasingly reliant on the immunohistochemical antibody technique. This method aids in the identification of lineage-associated or lineage-restricted antigens in hematolymphoid neoplasms. The demonstration of kappa or lambda light-chain restriction is a good indicator of monoclonality in B-cell processes, aiding in the distinction between benign reactive hyperplasia and malignant lymphoma. Increasing numbers of antibodies that react to cluster differentiation cell surface antigens have become available for use in paraffin-embedded sections, obviating the need for frozen tissue in many cases. This facilitates the collection, processing, shipping, and storage of tissue specimens for immunohistochemical studies. This report will discuss the basic concepts in the immunohistochemical technique and show its applicability to hematopathology. It will also describe the most relevant antigens/antibodies and how they are used in antibody panels for the diagnosis of benign and malignant hematolymphoid lesions.

Apoptosis-related genes and proteins in Hodgkin's disease

During recent years it has become increasingly evident that L&H cells in nodular lymphocytic predominance (LP) Hodgkin's disease (HD) and Hodgkin and Reed-Sternberg (H-RS) cells in approximately half the cases of classical HD originate from B-lymphocytes, and that H-RS cells in most of the remaining cases of classical HD express a null phenotype. The pathogenesis of HD is unknown. An association with Epstein-Barr virus (EBV) has been suggested and there are also indications that genes involved in programmed cell death (apoptosis) may be implicated. In this study, the expression of four apoptosis-related proteins (bcl-2, bcl-x, bax and p53) in 53 cases of HD was examined and the data were correlated with the genotype, the EBV status and the phenotype (B, T or null) of the neoplastic cells. The H-RS cells expressed a B-cell phenotype in 3/3 cases of nodular LP and in 19/ 50 (38%) cases of classical HD. The remaining cases showed a null-cell phenotype in 29/50 (58%) and a T-cell phenotype in 2/50 (4%). EBV was more often positive in B (14/19, 74%) than in null (7/29, 24%) type HD. The H-RS cells were bcl-2-positive in 19/53 (36%), bcl-x-positive in 17/53 (32%), bax-positive in 1/53, and p53-positive in 41/53 (77%) cases. No relationship was found between bcl-2 expression and EBV status, or between bcl-2 and bcl-x expression. A t(14;18) translocation was seen in 2 of 34 cases. P53 point mutations were not detected. Our findings indicate that nodular LP and classical HD originate from B-cells in a high proportion of cases. They also suggest a role for bcl-2, bcl-x and p53 in tumorigenesis. The pathogenesis is not known at this stage.

Practical applications of immunohistochemistry in hematolymphoid neoplasms

Immunohistochemistry plays a key role in the diagnosis and classification of hematolymphoid neoplasms. New cell and lineage markers are constantly being discovered and added to the existing long list of antibodies. In this review article we provide general information and new applications of the commonly used hematolymphoid markers. We also discuss the features and applications of some newly discovered markers, such as ALK, fascin, granzyme/perforin, and tryptase. There is no universal "panel" for the diagnosis of hematolymphoid neoplasms. However, in this review article, we provide suggested panels for a given hematolymphoid neoplasm that is based on our experience and that reported in the literature.

The malignant lymphomas of Kenya: morphology, immunophenotype, and frequency of Epstein-Barr virus in 73 cases

Recent information is limited regarding pathological features of the malignant lymphomas of Africa, other than Burkitt's lymphoma. In this study, we apply modern techniques and nomenclature to classify 73 lymphomas from a central histopathology laboratory serving 40 mission hospitals in Kenya. We were particularly interested in the frequency of recently recognized lymphomas and the incidence of Epstein-Barr virus in various lymphoma subtypes. Malignant lymphomas accounted for 12% of all surgical pathology specimens processed in the laboratory over the 21-month period included in the study. Patient age ranged from 4 to 97 years (median, 35 years). The male-to-female ratio was 2.5:1. Sixty lymphomas (82%) were non-Hodgkin's, and 13 (18%) were Hodgkin's disease. Of the non-Hodgkin's lymphomas (NHLs), 52 (87%) were B-lineage, including 21 (35% of NHLs) Burkitt's lymphomas (only one from the jaw), 11 (18%) diffuse large B cell lymphomas; nine (15%) small lymphocytic lymphomas, six (10%) Burkitt's-like lymphomas, two (3%) follicular lymphomas (two of two expressed bcl-2 protein; one of two showed bcl-2 major breakpoint region rearrangement), two (3%) mantle cell lymphomas, and one extranodal marginal zone lymphoma. Of the eight T cell lymphomas, six were precursor T-cell type, and the remaining two were peripheral T cell lymphomas, unspecified. The median age of the 13 patients (18% of lymphomas) with Hodgkin's disease was 23 years (range, 9 to 97 years). Six were nodular sclerosis, four were mixed cellularity, one case each was lymphocyte depletion, lymphocyte predominance, and unclassified Hodgkin's disease. Hodgkin's cells in 6 of the 12 nonlymphocyte predominance cases were positive for CD20, and in three of the six for CD45 as well. Epstein-Barr virus was identified using in situ hybridization for EBER 1 in the malignant cells of 22 of 39 informative lymphomas, including each of 17 Burkitt's lymphomas, and three of seven diffuse large B cell lymphomas. Of note, none of five Burkitt's-like lymphomas expressed EBER 1. One of two informative cases of peripheral T cell lymphoma, and four of nine cases of Hodgkin's disease were EBER 1 positive. In summary, T cell lymphomas and recently recognized B-lineage non-Hodgkin's lymphoma subtypes do not appear to be particularly common in East Africa.

Hodgkin's disease: old and recent clinical concepts

The diagnosis of Hodgkin's disease (HD) is still primarily based on the histopathologic criteria presented by Lukes et al in 1965. Over the past three decades, however, advances in immunohistochemistry, molecular studies, and virologic findings have provided evidence that HD exhibits significant heterogeneity. Whereas the nodular sclerosis subtype is the major subset of the "classic" disease, it has become evident that the nodular, lymphocytic predominance subtype may represent a minor distinct subset, and possibly a distinct disease entity. Furthermore, there is strong evidence that the mixed cellularity subtype may be an Epstein-Barr virus-related disorder. Finally, based on phenotypic and genotypic features, the existence of a "continuum" between a fraction of HD cases, including the lymphocytic depletion subtype, and CD30-positive anaplastic large cell lymphomas has been suggested.

Pregnancy-associated lymphomas. A clinicopathologic study

BACKGROUND

The natural histories of Hodgkin's disease (HD) and non-Hodgkin's lymphomas (NHL) during pregnancy are not well understood.

METHODS

All cases of HD and NHL diagnosed during pregnancy at Stanford University Medical Center since 1987 were reviewed and clinical follow-up was obtained. Various immunohistochemical studies and in situ hybridization for Epstein-Barr virus (EBV) encoded RNA were performed in a subset of cases.

RESULTS

Seventeen cases of HD and 12 cases of NHL were accessioned (median age; 27 yrs). The HD cases were classified as 13 nodular sclerosis type, 3 mixed cellularity type, and 1 unclassified. Clinical follow-up revealed most of the patients had Stage II to III disease and were diagnosed on average at 22 weeks gestation. Most of the patients deferred therapy until after delivery and had no evidence of disease at the last follow-up except for one death with disease but not from it. NHL were classified according to the working formulation as high or intermediate grade lymphomas of various types, including both nodal and extranodal sites. Clinical follow-up revealed most had Stage II to IV disease and were diagnosed on average at 23 weeks gestation. Patients with HD tended to survive longer than those with NHL (raw mortality, P = 0.04). In situ hybridization failed to provide support for the presence of EBV in a subset of patients with NHL.

CONCLUSIONS

The clinical behavior of these neoplasms during pregnancy does not appear to be significantly different from that outside of the setting of pregnancy. Treatment of selected HD patients apparently may be safely deferred until after delivery. Patients with NHL present with higher stage disease and have a poorer prognosis than those with HD.

Primary cutaneous Hodgkin's disease with evolution to systemic disease. Association with the Epstein-Barr virus

Hodgkin's disease rarely involves the skin and when it does is an indication of advanced stage disease. Primary cutaneous Hodgkin's disease is exceedingly rare, and only a few cases are reported. We describe a patient who developed multiple cutaneous lesions of Hodgkin's disease 2 years before manifesting nodal disease of mixed cellularity subtype. Reed-Sternberg cells in the skin as well as lymph nodes and bone marrow were positive for Epstein-Barr viral transcripts and expressed viral latent membrane protein. Epstein-Barr virus has not previously been demonstrated in primary cutaneous Hodgkin's disease, and its presence in lesions in all sites in this case supports a diagnosis of primary cutaneous disease with subsequent evolution into systemic disease.

T-cell-rich B large-cell lymphoma simulating lymphocyte-rich Hodgkin's disease

Immunophenotypic analysis of 50 cases fulfilling the histologic criteria for mixed cellularity Hodgkin's disease disclosed nine cases with a B-cell, non-Hodgkin's phenotype (CD20+, CD15-, CD30-, EMA-). The cases were characterized by a diffuse small lymphocytic milieu, interspersed atypical large cells including classic Reed-Sternberg cells, and infrequent plasma cells, eosinophils, and L&H cells. The male:female ratio was 7:2 (aged 22-65 years, median 39 years). Three patients were Ann Arbor stage II, two stage III, and four stage IV. The patients presented with generalized lymphadenopathy (four), mesenteric lymph node involvement (two), splenomegaly (four), and bone marrow involvement (three). Four patients were treated with standard Hodgkin's disease protocols. Two attained a complete response and two a partial response; all relapsed and died. Four of five patients treated for large-cell lymphoma achieved a complete response and are currently alive without evidence of disease. The one patient with an initial partial response relapsed and died. We conclude that immunophenotypic analysis is essential in cases of histologic mixed cellularity Hodgkin's disease, especially in those with lymphocyte-rich morphology. Cases with a B-cell phenotype should be diagnosed and treated as T-cell-rich B large-cell lymphoma.

Nodular type of lymphocyte predominant Hodgkin's disease. A clinical study of 50 cases

BACKGROUND

Lymphocyte predominant Hodgkin's disease (LP-HD), particularly that with a nodular pattern has been suggested to constitute a distinct disorder within the spectrum of Hodgkin's disease, this issue being based on clinical, morphological and immunological observations. Furthermore, the nodular LP-HD (N-LP-HD) has been considered to differ from the diffuse subtype (D-LP-HD), although the data are conflicting. The question addressed in this study was whether the clinical course of N-LP-HD differs from that of the D-LP-HD as well as the other subtypes of Hodgkin's disease.

PATIENTS AND METHODS

90 cases diagnosed as LP-HD at St. Bartholomew's Hospital (SBH) were reviewed. The histopathological classification was based on the original Lukes and Butler criteria for classical N-LP-HD. Clinical data were retrieved from case notes and a computer database. Stage was determined by the Ann Arbor criteria. Survival and remission duration analyses were performed for the group of patients with N-LP-HD and compared with an histological control group of patients with the other subtypes of Hodgkin's disease and the cases of LP-HD that have been reclassified.

RESULTS

1. 50/90 cases (56%) originally diagnosed as N-LP-HD qualified as N-LP-HD. No case with the diffuse subtype, could be identified. Twenty-three percent of the cases were reclassified as Mixed Cellularity and 11% as Nodular Sclerosis HD, whilst 10% as non-Hodgkin's lymphomas. 2. The majority of cases (78%) presented with early stage (I + II). Bone marrow and liver involvement were rare. 3. 92% of cases achieved complete remission. Recurrence developed in only 6/46 patients within 5-12 years. A second complete remission was achieved in 5/6 (83%) cases. Further recurrences have not yet occurred. 4. The overall survival of the 50 cases with N-LP-HD was 92% at 4 years and did not differ significantly from the 40 cases that have been reclassified. Remission duration however, was significantly better for the group of N-LP-HD being 81% at 12 years. 5. Second malignancies were common and developed in 6/50 cases (12%) with N-LP-HD within 10-15 years. These included: ALL (1 case), high grade B-NHL (2 cases), squamous cell carcinoma (1 case), glioma (1 case), lung carcinoma (1 case). 6. 12/50 patients died within a period of follow-up, up to 21 years. 1/3 of the deaths was attributed to the development of second malignancy.

CONCLUSIONS

The diffuse variant of LP-HD is rare, having not been seen at St. Bartholomew's Hospital during this time period. The 50 cases with N-LP-HD showed a favourable course with presentation at an early stage, good response to treatment, late recurrences and remission duration other than the other subtypes of HD. The latter could be attributable to the early stage at presentation of N-LP-HD, since the remission duration on a matching on stage analysis was superficially better in favour of N-LP-HD (p = 0.06). The indolent course of the disease in combination with the risk of second malignancy cases raises the question whether histology should be taken into consideration in the development of new protocols for HD.

Cutaneous Hodgkin's disease: an immunohistochemical analysis

Studies of skin involvement in Hodgkin's disease are infrequent in the literature. In particular, immunophenotypic analyses of specific cutaneous infiltrates have been performed in only a few cases. We analyzed the clinical, histological and immunohistochemical features of specific cutaneous manifestations of Hodgkin's disease comparing histologic and immunophenotypic aspects of skin lesions with those of the nodal counterpart. Seven patients with Hodgkin's disease of the lymph nodes and specific cutaneous lesions, where both nodal and skin biopsies were available for histologic and immunohistochemical analyses, were included in this study. Immunohistochemical stains were performed with a 3-step immunoperoxidase technique on routinely-fixed, paraffin-embedded tissue sections. All 7 patients had nodular sclerosis Hodgkin's disease of the lymph nodes. In the skin, clinical presentations included reddish-brown papules, plaques, nodules and ulcerated tumors. Histologic examination of cutaneous lesions showed features consistent with nodular sclerosis Hodgkin's disease in 6 cases and unclassifiable Hodgkin's disease in one. Reed-Sternberg cells and lacunar cells were present in 4 cases (57.1%). Immunohistochemical analysis of Hodgkin's and Reed-Sternberg cells revealed a constant positivity for CD30 (BerH2) and negativity for CD45 (LCA) in both the lymph nodes and the skin. Staining with CD15 (M1) revealed positivity in 7/7 nodal samples and 5/7 skin biopsies. Cytoplasmic expression of immunoglobulin light chains (both lambda and kappa) was observed in one cutaneous case. The accompanying infiltrate was mostly composed of T-lymphocytes admixed with variable numbers of monocytes/macrophages and eosinophils. Our results indicate that the histology of cutaneous specific manifestations of Hodgkin's disease correlates with that of the nodal counterpart in most cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Decreased expression of cellular markers in Epstein-Barr virus-positive Hodgkin's disease

Epstein-Barr virus (EBV) has been demonstrated in the Reed-Sternberg cells and their mononuclear variants (Hodgkin cells; H-RS cells) in a substantial number of Hodgkin's disease (HD) cases. Moreover, EBV can modulate both in vivo and in vitro the expression of several cellular genes, including lymphoid differentiation markers. Therefore we investigated, in 64 cases of HD, the relationship between the presence of EBV and the expression of lymphoid (CD45RB), T- (CD3, CD45RO), B- (CD20, MB2 antigen, CDw75), and myeloid-cell lineage markers (CD15), and of activation markers (CD30, EMA, and the 115D8 antigen) on the H-RS cells. EBV-positive cases, as demonstrated by the presence of EBER-1 and -2 RNA and LMP-1 protein expression, showed a significant reduction in the expression on H-RS cells of T-cell lineage (CD3, P < 0.02), B-cell lineage (CD20; P < 0.005), and activation markers (EMA; P < 0.002 and the 115D8 antigen; P < 0.001) as compared with EBV-negative cases. No differences were found in the expression of CD15, CD30, CD45RO, CD45RB, CDw75, or the MB2 antigen on H-RS cells in EBV-positive and EBV-negative HD cases. Interestingly, in 11 cases of EBV-negative HD, B- as well as T-cell lineage markers could be found on some H-RS cells. These data suggest that EBV in H-RS cells is able to down-regulate the expression of T- (CD3) and B- (CD20) cell lineage markers and lymphoid activation markers (EMA and the 115D8 antigen).(ABSTRACT TRUNCATED AT 250 WORDS)

The expression of the B-cell marker mb-1 (CD79a) in Hodgkin's disease

Recent evidence indicates that membrane-bound immunoglobulin on B lymphocytes is associated with a molecule which comprises the products of the mb-1 and B29 genes. This molecule is a highly specific marker for B-cells, presumably because of its central functional role in antigen triggering, and has recently been clustered as CD79a at the 5th Leucocyte Workshop. Recently there has been controversy surrounding reports of B-cell antigen expression by Reed-Sternberg and related cells, and we have therefore studied 108 cases of Hodgkin's disease immunohistochemically using a novel antibody which detects mb-1 protein in paraffin sections. The results were compared with those achieved using antibody L26 to detect CD20. The mb-1 protein was present in the neoplastic cells in all 14 cases of lymphocyte predominance Hodgkin's disease studied, and CD20 immunoreactivity was also found in seven of the eight cases of this subtype studied. Of the non-lymphocyte predominance cases, 20% (19/94) expressed mb-1 and 30% (20/67) CD20 in the Reed-Sternberg cells, but the cells positive for either of these two markers usually constituted only a very small proportion of the neoplastic population. However, in occasional cases (one of 94 for mb-1 and five of 67 for CD20), more than 50% of the neoplastic cells expressed one or both B-cell antigens. These results confirm the B-cell origin of the neoplastic cells in lymphocyte predominance Hodgkin's disease, but they also indicate that, contrary to our previous study, mb-1 expression may occasionally be found in what appears, on histological grounds, to be other types of Hodgkin's disease.

Primary splenic large cell anaplastic lymphoma associated with HIV infection

We report a case of primary splenic B-cell CD30 positive large cell anaplastic lymphoma developing in an HIV positive patient. The tumour cells expressed Epstein-Barr virus-associated antigens.

Long-term prognostic importance of primary Ki-1 (CD30) antigen expression and anaplastic morphology in adult patients with diffuse large-cell lymphoma

BACKGROUND

We retrospectively assessed the long-term prognostic importance of primary CD30 antigen expression and of anaplastic large-cell morphology (ALCL) in adult patients with previously untreated diffuse large-cell lymphoma (DLCL), including cases of immunoblastic lymphoma, and identified their clinical features.

MATERIALS AND METHODS

We examined available archival paraffin-embedded or frozen pathologic material and medical records of adult patients with previously untreated DLCL seen at M.D. Anderson Cancer Center (MDACC) between January 1978 and May 1989.

RESULTS

Sixty-seven cases of DLCL and seven cases of IBL (a total of seventy-four heretofore referred to as DLCL) were identified. Twenty-two of the 74 patients were positive for the CD 30 antigen. For these 22 patients the rates of complete remission, survival, and time to treatment failure (TTF) were 86%, 82%, and 77%, respectively, at 81 months. When compared with the group of 54 patients which stained negative for CD 30, the long term survival of CD 30-positive DLCL was favorable (82% vs. 49%, p = 0.08). ALCL morphology was present in two-thirds of the patients with CD 30-positive DLCL but did not affect survival and TTF rates. Among patients with CD 30-positive DLCL, 16 patients without skin involvement were younger and had a low failure rate (13%) compared with six patients with skin involvement who were older and had a high failure rate (50%); however, the latter group had a more indolent course after failure and thus both groups had similar survival rates.

CONCLUSIONS

Primary CD 30 positivity is associated with a favorable long-term prognosis in adult patients with DLCL treated with doxorubicin-containing chemotherapy. ALCL morphology among these patients does not affect the outcome. Patients with CD30-positive DLCL and skin involvement have a higher failure rate than those without skin involvement, but similar overall survival.

Immunohistochemical characteristics of Hodgkin and Reed-Sternberg cells in relation to age and clinical outcome

One hundred and fifty-four cases of Hodgkin's disease diagnosed between 1985 and 1988 from an unselected population were stained with a panel of six monoclonal antibodies; LN1, MB2, L26 (CD20), all B-cell antibodies, UCHL1 (CD45 RO), mainly T-cell antibody, Leu M1 (CD15), Ber H2 (CD30) and the polyclonal CD3, T-cell antibody. The results were related to age, histopathological subgroup and prognosis. There was no significant difference in staining patterns in the 90 patients below the age of 60 compared with the 54 patients above that age. In the entire group, significantly fewer mixed cellularity cases were positive with Ber H2 and Leu M1 compared to nodular sclerosis. Disease-free survival tended to be better for cases stained with T-cell related antibodies. This study thus indicated differences in behaviour between T-cell positive and negative Hodgkin's disease and that there are antigenic differences between nodular sclerosis and mixed cellularity subgroups. We could not, however, show any phenotypic differences between the tumour cells in young and old patients.

Proliferating cell nuclear antigen (PCNA) and nucleolar organiser regions in Hodgkin's disease: correlation with morphology

AIM

To define the distribution of proliferating cell nuclear antigen (PCNA) and silver staining nucleolar organiser regions (AgNORs) in Hodgkin's disease.

METHODS

PCNA was shown in a series of 34 cases of Hodgkin's disease using immunohistochemical methods. In a second series of 46 cases the AgNOR technique for interphase nucleolar organiser regions was studied. Both series comprised routinely fixed and processed paraffin wax sections of three main Rye subtypes.

RESULTS

In all cases, regardless of Rye subtype, most Sternberg-Reed cells and mononuclear Hodgkin cells showed nuclear PCNA immunoreactivity and such cells had 15 or more AgNOR sites. The Hodgkin cells had, in general, about half the number of AgNORs seen in Sternberg-Reed variants.

CONCLUSIONS

These data support the notion that Hodgkin's disease can be regarded as a high grade lymphoma, the large Hodgkin's and Sternberg-Reed cells being the (PCNA positive and AgNOR rich) neoplastic elements with high proliferative capacity. A smaller proportion of the associated cells also showed evidence of proliferation.

Classification of Hodgkin's disease biopsies by a panel of four histopathologists. Report of 1,140 patients from the German National Trial

First results from reviewing the diagnostic biopsies of Hodgkin's lymphomas (HL) are reported. Biopsies from 1,140 patients were evaluated by consensus diagnoses according to an extended classification of the British National Lymphoma Investigation. 95 of the recruited cases (8.3%) were omitted and not approved as Hodgkin's lymphoma. The remaining 1,045 biopsies were classified as follows: Lymphocytic predominance 31 (2.7%); Nodular sclerosis (NS) 660 (57.9%), Mixed cellularity (MC) 159 (13.9%); Lymphocytic depletion 8 (0.7%); unclassifiable Hodgkin's 148 (13.0%). The unproved Hodgkin's cases [95 (8.3%)] were divided into non-Hodgkin's lymphomas 32 (1.9%), uncertain due to inadequate techniques 32 (2.8%), borderline between Hodgkin's- and Non-Hodgkin's lymphoma 23 (2.0%). Major dissent on this question involved 17 cases (1.5%) and 1 case which was non-malignant. All unclassifiable, borderline or dissent cases were reassessed after the histologic techniques were improved, and immunophenotyping and clinical data reevaluated. The rate of agreement among the observers was about 81.6%, varying between 23.8% in grade 2 NS to 85.0% in both NS groups. Only 62.8% of all primary diagnoses were approved by the final diagnoses of the panel. Important differences in the classification of the British National Lymphoma Investigation concerns the NS-group and mainly its grade 2 subtype. MC was identical in both classifications. Clinico-pathologic correlation of actuarial survival times revealed a significantly worse outcome of MC vs NS, < 20% after 80 months observation. Only slightly significant better survivals were found in grade 1 vs grade 2 NS. Significant differences in unclear compared to all Hodgkin's, were found and the worst survival was in the NHL group.

Immunohistochemistry of Hodgkin and non-Hodgkin lymphomas with emphasis on the diagnostic significance of the BNH9 antibody reactivity with anaplastic large cell (CD30 positive) lymphomas

BACKGROUND

Morphologic and immunohistologic studies were performed on a series of 213 lymphoma cases, including CD30-positive anaplastic large cell (ALC) lymphomas (45 cases), other CD30-positive (18 cases) or CD30-negative (72 cases) non-Hodgkin lymphomas (NHL), cases of Hodgkin disease (HD) (73 cases), and an additional 5 cases exhibiting features of both CD30-positive ALC and Hodgkin lymphomas.

METHODS

The aim was to assess differential expression by tumor cells of CD30/BerH2, epithelial membrane antigen (EMA), and other monoclonal antibodies, including BNH9, an epithelial and endothelial marker that has been found to be reactive with ALC lymphoma cells.

RESULTS

A significantly greater proportion of cases of ALC lymphoma compared with HD exhibited positive results for CD45, EMA, CD45RO, and CD3 in CD30-positive atypical large cells, whereas Reed-Sternberg cells in HD most frequently coexpressed CD15 and CD30 antigens. ALC lymphoma cells reacted with BNH9 MoAb in 10 of the 42 (23.8%) assessable cases, whereas Reed-Sternberg cells reacted with this antibody in 5 of 73 (6.8%) HD cases. Only 3 of 90 (3.3%) NHL cases had positive results for BNH9; they were CD30-negative high-grade or low-grade lymphomas. It was noteworthy that 9 of 10 BNH9-positive ALC lymphomas also were EMA positive. Four of the five cases with morphologic features intermediate between those of HD and ALC lymphoma showed immunohistologic findings (positive results for CD30 and CD15, negative results for EMA, CD45, and BNH9) similar to those frequently observed in the HD cases; conversely, the remaining case showed a profile (positive results for CD30, CD45, and EMA, negative results for CD15) typically observed in ALC lymphomas.

CONCLUSIONS

This study suggests that the differential expression of CD45, EMA, and CD15 could be used in the distinction of ALC lymphomas and HD, whereas it seems that BNH9 antibody reactivity may be of diagnostic use only in that it reinforces the diagnostic value of EMA expression in the differentiation of these entities.

CD30 (Ki-1)-positive, anaplastic large cell lymphoma mimicking gastrointestinal carcinoma

BACKGROUND

There is great diversity in the clinical presentation of CD30 (Ki-1)-positive, anaplastic large cell lymphoma (ALCL). The authors report two patients in whom the clinical and morphologic features mimicked gastrointestinal carcinoma.

METHODS

Surgical pathology specimens were examined using standard histologic techniques. Paraffin- and frozen-section immunohistochemistry was performed by an avidin-biotin-peroxidase method.

RESULTS

The first patient is a 58-year-old man who presented with a constricting mass of the sigmoid colon. Immunohistochemical staining for CD45 (LCA) was negative in formalin-fixed paraffin sections. However, CD45 and CD74 (LN2) were detectable in B5 postfixed material. The second patient is a 44-year-old woman who presented with dysphagia and back pain. Endoscopic examination revealed an ulcerated luminal mass in the proximal esophagus and a gastric ulcer. Mucosal biopsy specimens of the esophagus and stomach contained ALCL, which was CD45 positive. Retroperitoneal lymph nodes contained ALCL infiltrating the sinuses, interfollicular areas, and blood vessel lumina. In addition to CD45 and pan-T-cell antigens, the neoplastic cells expressed CD68 (KP1) and epithelial membrane antigen (EMA). Monoclonal antikeratins were negative, but a polyclonal antikeratin stain was positive.

CONCLUSIONS

These findings indicate that clinical, morphologic, and some immunologic features of ALCL may mimic gastrointestinal carcinoma.

Recent results on the biology of Hodgkin and Reed-Sternberg cells. I. Biopsy material

The most recent sophisticated investigations have provided new and revealing, but also contradictory and controversial information on the biological nature and the cellular origin of Hodgkin and Reed-Sternberg cells (H-RS). Immunophenotypic analyses have shown variable phenotypic antigen expression; but, on balance the data suggest a lymphoid cell expressing T- and/or B-cell-associated markers and certain activation antigens while lacking immunological features of monocytes-macrophages or other lineages. Molecular genetic studies have demonstrated heterogenous findings with respect to rearrangements of T-cell receptor and immunoglobulin genes. Only a small percentage of the cases has rearrangements; this might be due to the threshold of sensitivity of the method combined with the scarcity of the malignant cells. Epstein-Barr virus (EBV) genomes are clonally integrated in the H-RS cells of about half the cases. The significance of these findings--whether EBV is a causative agent or an epiphenomenon--remains to be elucidated. H-RS cells express mRNA and proteins of various cytokines and cytokine receptors implying a predominant role for cytokines in the pathophysiology of HD. The mononuclear and polynuclear H-RS cells are capable of DNA synthesis and nuclear division; the lack of cellular division leads to multinuclearity through the process of endomitosis. Mutations and expression of only a limited number of oncogenes have been tested thus far. Whether the bcl-2 oncogene is involved in HD remains a matter of debate. Aneuploidy and non-random chromosomal abnormalities are the results of cytogenetic analyses of H-RS cells. However, no chromosomal marker specific for HD has yet been found. Thus, while studies of EBV involvement, growth factor production, oncogene expression and chromosomal abnormalities contributed a fair amount of new data on the nature of H-RS cells, only immunophenotyping and genotyping provided some indication of the cellular derivation: an activated lymphoid cell that possibly expresses oncogenes, that probably is infected with EBV, that most likely produces cytokines, that certainly has multiple karyotypic abnormalities.

Paraffin section immunohistochemistry in the diagnosis of Hodgkin's disease and anaplastic large cell (CD30+) lymphomas

Morphological and immunohistological studies were carried out on a series of 137 lymphomas including CD30+ anaplastic large cell (ALC) lymphomas (48 cases) and non-lymphocyte predominant Hodgkin's disease (HD) (89 cases), with the aim of assessing in situ expression of a combination of antibodies including anti-CD30/BerH2, epithelial membrane antigen (EMA), CD15 and CD45, in addition to other monoclonal antibodies suitable for paraffin tissues. A greater proportion of cases of ALC lymphomas than of HD exhibited positivity for CD45 (91.7% vs 17.6%), EMA (56.2% vs 4.5%), CD43 (53.6% vs 13.1%) and CD45RO (39.5% vs 3.5%), whereas Reed-Sternberg (RS) cells in HD most frequently expressed CD15 (93.2% vs 20.8%) antigen. Moreover, in 35 of 48 (72.9%) ALC lymphomas tumour cells expressed the CD30+, CD45+, CD15-, EMA- or + phenotypic profile, while in the same percentage (62/85) of HD cases RS cells were found to express the CD30+, CD45-, CD15+, EMA- profile. This study suggests that the differential expression of CD45, EMA, and CD15 may be used in the separation of ALC lymphomas and HD. However, co-expression of CD30, CD45 and CD15 antigens by RS cells in HD (14/85 cases, 16.5% in this series) and by tumour cells in ALC lymphomas (9/48 cases, 18.7% in this series) may be encountered in a non-negligible fraction of cases.

Anaplastic large cell Ki-1 lymphoma in the central nervous system: report of an autopsy case

A 45-year old immunocompetent man presented with multiple lesions in the brain. A histological examination of the tumors showed a diffuse infiltrate of lymphoid cells with cellular polymorphism and of multinucleated giant cells. These cells were immunolabeled with antibodies against B cell lineage and with a monoclonal antibody, Ber-H2 (CD30), which showed the presence of Ki-1 antigen. Recently, among systemic non-Hodgkin's lymphomas, attention has been given to Ki-1-positive lymphomas, which have been incorporated in the up-dated Kiel classification. We report here a case of Ki-1-positive lymphoma arising in the CNS and review previously reported cases.

Ki-1 large cell lymphoma with regressing lesions in a child

An 8-year-old boy was seen with a cutaneous Ki-1 anaplastic, large cell lymphoma with multiple lesions. Some of the lesions showed spontaneous regression. During more than seven years of disease no systemic involvement was observed, but recurrent, self-healing lesions did appear. Histopathologic examination of five lesions revealed a variety of findings, from an inflammatory infiltrate to a highly anaplastic pattern. The neoplastic cells expressed Ki-1 and leukocyte common antigens. Ultrastructurally, those cells showed ruffled indentations. The differential diagnosis includes microvillous malignant lymphoma. The patient has had a four-year follow-up without relapses.

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.

Large cell anaplastic lymphoma: evaluation of immunophenotype on paraffin and frozen sections in comparison with ultrastructural features

Eleven cases of large cell anaplastic lymphoma (T type n = 5, B type n = 4, 0 type n = 2) were investigated using electron microscopy and immunophenotyping on formalin-fixed paraffin sections and frozen sections of fresh tissue, to determine whether morphological criteria exist for the discrimination of T, B, and 0 phenotypes. Tumour cell lineage could not be established from ultrastructural features. On paraffin material monoclonal B-cell markers Ki-B5 and L-26 served as reliable tools for recognizing the B phenotype of large cell anaplastic lymphomas (previously determined on fresh material). whereas monoclonal antibodies MT1 (CD43) and UCHL1 (CD45RO) were of limited value in lineage determination.

Large B-cell lymphoma rich in T-cells and simulating Hodgkin's disease

Unusual clinicopathological features drew our attention to nine of 208 cases diagnosed as Hodgkin's disease. Lymph node biopsy specimens in these cases were immunostained with monoclonal antibodies against B-cell, T-cell and Reed-Sternberg cell associated antigens and epithelial membrane antigen (EMA). Reed-Sternberg-like and other atypical large cells were dispersed in a diffuse, small lymphocyte-rich background, consistent more often with the initial diagnosis of diffuse, lymphocyte predominance Hodgkin's disease. The clinical stage in these cases was unusually advanced (stages III and IV). Splenomegaly was a common feature (six of nine cases), the male to female ratio was 7:2 and the median age was 55 years (range 25-77). Response to recognized regimes for Hodgkin's disease treatment was poor in most cases, and three patients died early of their disease. Large cells were B-lymphocytes expressing EMA--an immunophenotype similar to nodular, lymphocyte predominance Hodgkin's disease. Reed-Sternberg cell and T-cell associated antigens were absent on large cells. Mature T-cells, with nuclear irregularities in some instances, predominated in the background. A more appropriate diagnostic category is, therefore, T-cell-rich B-cell lymphoma. The cases represent a 4-5% erroneous diagnosis of Hodgkin's disease and further suggest that there is a need for revision of criteria for the diagnosis of the diffuse, lymphocyte predominance variant.

Persistence of Epstein-Barr virus in Reed-Sternberg cells throughout the course of Hodgkin's disease

Non-isotopic in situ hybridization employing digoxigenin-labelled DNA probes has been used to localize Epstein-Barr virus (EBV) in 55 cases of Hodgkin's disease (HD). The virus was found in Reed-Sternberg (RS) and mononuclear Hodgkin's cells in nine patients (16 per cent). Further samples taken at different times from three patients also showed the presence of EBV in the malignant cell population. Estimations of the number of EBV genomes present per cell suggested wide variations between different patients, but relatively constant amounts in different samples from the same patient. These findings are compatible with a stable infection of the neoplastic cells and support the notion that EBV may play a role in the development of HD in these patients. We also found evidence for the presence of EBV in a small percentage of non-neoplastic cells in 8 of the 55 samples. This suggests that isolation of EBV from HD tissue does not always signify a pathogenetic role for the virus. Furthermore, it is apparent that a high percentage of HD tissues do not contain demonstrable EBV, and the virus is therefore unlikely to be a causative agent for all cases of HD.

Clinicopathologic study of large cell anaplastic lymphoma (Ki-1-positive large cell lymphoma) among the Japanese

The clinical, prognostic, phenotypic, and genotypic findings of 30 patients with large cell anaplastic lymphoma (Ki-1-positive large cell lymphoma) were analyzed. There were 13 male and 17 female patients (male-female ratio, 0.8) whose ages ranged from 3 to 81 years of age (mean, 28 years of age; 67% of the patients younger than 30 years of age). The 5-year survival rate was 52%; this was better than that of other types of high-grade peripheral T-cell lymphoma. Histologic examination showed distinctive morphologic features such as tumor cell pleomorphism, sinus infiltration, fibrosis, partial lymph node involvement, sparing of B-cell regions, and occasional plasma cell infiltrates. Eighty percent of the cases were of T-cell phenotype, and others expressed neither B-cell nor T-cell markers. The tumors were frequently positive for a histocompatibility antigen (HLA-DR), CD25 (the interleukin-2 receptor), and epithelial membrane antigen. Rearrangements of the T-cell receptor beta gene were observed in nine of 13 cases (69%). These findings indicated that many of the tumors had the phenotype and genotype of activated T-cells. This study also showed that large cell anaplastic lymphoma has a survival figure intermediate between Hodgkin's disease and low-grade peripheral T-cell lymphoma.

Lymphocyte predominance Hodgkin's disease (nodular paragranuloma)--a bcl-2 negative germinal centre lymphoma

Hodgkin's disease, lymphocyte predominance type (nodular paragranuloma), is of germinal centre origin and the tumour cells have a B-cell phenotype. As the T(14;18) translocation, and the subsequent expression of bcl-2 protein by germinal centre cells, is the most characteristic finding of centroblastic-centrocytic lymphoma, we have tested a series of 11 cases of lymphocyte predominance Hodgkin's disease, using Southern blot analysis for the major breakpoint region and the minor breakpoint cluster region, polymerase chain reaction with primers for the major and minor breakpoint cluster region, and immunohistological studies with a monoclonal antibody specific for the bcl-2 protein. All three techniques gave negative results in the cases of Hodgkin's disease, establishing a clear differentiation from centroblastic-centrocytic lymphoma. These findings are useful in the differential diagnosis between the two entities and raise the question of the non-clonal nature of lymphocyte predominance Hodgkin's disease.

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.

Non-Hodgkin's lymphoma involving the tonsil: an immunohistochemical study

Twenty-one patients with non-Hodgkin's lymphoma involving the palatine tonsil were studied in an attempt to relate pathological data to clinical outcome. Eleven tumours were classified as low-grade and ten as high-grade on morphological criteria. The results of immunohistochemical investigations are presented; all tumours but one were of B-cell origin. None of the pathological factors studied were found to be useful prognostic indicators.

Localization of immunoglobulin light chain mRNA expression in Hodgkin's disease by in situ hybridization

In situ hybridization techniques were used to detect immunoglobulin light chain messenger RNA (mRNA) in 28 formalin-fixed, paraffin-embedded samples of Hodgkin's disease. Cocktails of biotinylated oligonucleotide probes specific for the constant regions of kappa and lambda light chain mRNA were used. None of the Reed-Sternberg cells or their variants in any of the cases studied showed positive staining with either probe, in contrast to normal plasma cells which showed strong staining in the same sections. It was concluded, therefore, that the cytoplasmic immunoglobulin frequently detected within these cells by immunocytochemistry is present not as a result of synthesis, but as a result of some other mechanism.

Twelve cases of Ki-1 positive anaplastic large cell lymphoma of skin

In seven of 12 cases of Ber-H2 (Ki-1) positive anaplastic large cell non-Hodgkin's lymphoma (Ki-1 ALCL) disease remained localised to skin, and in five there was extracutaneous spread. Four patients had histological evidence of pre-existing or coexisting mycosis fungoides, and three patients had a long standing history of eczema or ichthyosis. In two cases the presence of a T phenotype was shown in frozen sections, and in a further six cases a T phenotype was firmly established in paraffin wax sections. Four patients died less than one year after presentation (two with disseminated lymphoma; two from other causes); one died at five years with widespread lymphoma and the remaining seven cases were alive one to 14 1/2 years after presentation. Three of the four patients with associated mycosis fungoides had prolonged survival, contrary to the findings of previous reports which suggest secondary Ki-1 ALCL behaves aggressively. The recognition of these tumours is important because of their relatively good prognosis. The diagnosis can be readily substantiated immunohistochemically, using a simple panel of antibodies.

Long-term survival in Ki-1 lymphoma

Three patients with histologic and immunologic features of Ki-1-positive large cell lymphoma, who experienced long-term survival, are presented. These three patients at 2, 28, and 49 years of age had adenopathy; all cases had been initially misdiagnosed as metastatic carcinoma or malignant histiocytosis. On subsequent review, they had sinusal and diffuse growth of large pleomorphic cells that were Ber-H2 (Ki-1; CD 30) positive. One case marked as a T-cell lymphoma with UCHL1, one case expressed T-cell and B-cell markers, and one case was negative for both T-cell and B-cell markers. All patients received chemotherapy, and two received local radiation. One patient was not treated until 9 years after initial diagnosis. Two patients had several recurrences, but there has been no evidence of lymphoma in any of the three patients for 63 to 301 months; overall survival time has ranged from 14 to 25 years. These cases are the longest reported survivors with Ki-1 lymphoma; 5 years was the longest survival time previously reported. It also is noteworthy that Ber-H2 and other lymphoid-associated antigens appear to be preserved in formalin-fixed, paraffin-embedded tissues for prolonged periods. This may allow retrospective studies to evaluate the natural history of Ki-1 lymphomas, as well as their spontaneous or treatment-induced regression.

CD30 expression in follicular lymphoma

The CD30 antigen is a characteristic phenotypic feature of Sternberg-Reed and Hodgkin cells and is also found in a subset of large cell non-Hodgkin's lymphomas. The finding of CD30 positive cells in some centroblastic/centrocytic (cb/cc) follicular lymphomas prompted us to characterize the presence and distribution of CD30 positive cells in this type of lymphoma, using the monoclonal antibody BerH2. CD30 positive cells were present in 17/19 of the cases studied, located mainly at the edge of the neoplastic follicles, but also in some cases in perinodular or T-cell areas. This distribution resembles that found in reactive tonsils and lymph nodes. The majority of these CD30 positive cells in cb/cc lymphoma seem to be B-cells, as suggested by their reactivity with B-cell markers demonstrated by double immunostaining. The nature of these CD30 positive cells is unclear, but they should be taken into consideration in the differential diagnosis of cb/cc lymphoma with lymphocyte predominance Hodgkin's disease.