Breakpoints of the t(11;18)(q21;q21) in mucosa-associated lymphoid tissue (MALT) lymphoma lie within or near the previously undescribed gene MALT1 in chromosome 18

Lymphomas arising in mucosa-associated lymphoid tissue (MALT) are indolent B-cell tumors that have a predilection for epithelial sites and often develop in a setting of chronic inflammation or autoimmunity. As many as 50% of low-grade MALT lymphomas contain an (11;18)(q21; q21) chromosomal translocation. Using fluorescence in situ hybridization, we have analyzed the position of recombination within chromosome 18 DNA in three examples of MALT lymphoma bearing this translocation. In all three cases, the breakpoint maps to DNA in BAC b357H2, covering about 150 kb of sequence. A previously undescribed, ubiquitously expressed gene, which we refer to as MALT1, was identified within this sequence and was found to be broken in one case for which we have definitively located the position of recombination between chromosomes 18 and 11. The sequence of this gene indicates the presence of two immunoglobulin-like C2 domains and a region of partial homology to caspases, suggesting a possible role for MALT1 in the regulation of apoptosis.

[Reproducibility and prognostic value of histopathological classifications of malignant lymphomas. Prolegomena for the 1st international classification proposed by WHO. Group of the non-Hodgkin's Malignant Lymphoma Classification Project]

Different histopathologic classifications have been used in the study of malignant lymphomas. The clinical relevance (reproducibility, prognostic value) has not been precisely studied. The "non-Hodgkin's lymphoma classification project" has been organized to study a cohort of 1,403 cases in 9 sites around the world consisting of consecutive patients seen between 1988 and 1990 in order to have a good follow-up. The reproducibility of the up-dated Kiel and the ILSG (REAL) classifications between the 5 visiting expert hematopathologists was pretty good, at least 85% for the majority of the entities. According to survival curves, the lymphomas can be stratified in 4 different groups. Comparison with the international prognostic index demonstrate that for therapeutic strategy both histopathology and index should be used. The results bring a good support to the project of the WHO to propose the first international classification of lymphomas based on both forme classifications.

Lymphomatoid papulosis: a T-cell dyscrasia with a propensity to transform into malignant lymphoma

OBJECTIVE

To describe the diagnostic difficulties, response to therapy, and clinical features of lymphomatoid papulosis and the cumulative frequency of transformation to lymphoma.

DESIGN

Case series.

SETTING

University hospitals.

METHODS

The records of 21 patients with lymphomatoid papulosis who were seen from 1986 to 1993 were retrieved from the archives of two institutions. The entry criteria for the study were lymphomatoid papulosis misdiagnosed at the time of original presentation or lymphomatoid papulosis that later developed into lymphoma.

RESULTS

When lymphomatoid papulosis tissues are pathologically examined, they are frequently confused with lymphoma, melanoma, or carcinoma. Eight of the 19 patients whose condition was misdiagnosed as malignant received either chemotherapy or radiotherapy. Although lymphomatoid papulosis responded to cytotoxic chemotherapy, the remissions were transient and promptly recurred after or during treatment. However, all five cases that became malignant responded to chemotherapy and have not recurred. Five of 21 patients (24%) developed lymphoma, but the cumulative risk for transformation after 15 years was 80%.

CONCLUSIONS

Lymphomatoid papulosis can only be diagnosed accurately through a careful history in which the characteristic waxing and waning of the skin lesions is identified and through proper communication between clinicians and pathologists. Patients with lymphomatoid papulosis have an increased risk for developing lymphoma that is much higher than the 15% to 20% quoted in the literature. Patients who develop lymphoma respond well to cytotoxic chemotherapy and can be cured with appropriate therapy. Internists and oncologists need to be aware of lymphomatoid papulosis and its characteristic clinical features so that this disorder is accurately diagnosed and so that unnecessary and potentially hazardous treatment is avoided.

Detection of Eber-1 RNA in primary brain lymphomas in immunocompetent and immunocompromised patients

Tissue from primary central nervous system lymphoma (PCNSL) which developed in five patients with acquired immuno deficiency syndrome (AIDS), nine patients without immunodeficiency, and two Epstein-Barr virus (EBV)-positive control cell lines (B95-8 and Raji) were examined for the presence of EBER-1 RNA. The tissues were hybridized with digoxigenin-labeled sense or anti-sense EBER-1 riboprobes. In all five AIDS-related PCNSLs, strong hybridization signals were found with the EBER-1 anti-sense probe. Signals could be eliminated by preincubation of the tissues with RNase-A. Hybridization with the EBER-1 sense probe showed no signal. All PCNSLs from immunocompetent patients (five paraffin-embedded, four frozen) showed no hybridization signals with EBER-1 sense or antisense probe but good hybridization signals with probes to immunoglobulin kappa or lambda light chain indicating RNA preservation. The paraffin-embedded B95-8-positive control cell-line showed positive hybridization in most cells with the anti-sense EBER-1 probe, and up to one percent of the cells had a weak signal with the sense probe. Most Raji cells showed a uniform signal with the anti-sense EBER-1 probe only. We conclude that, PCNSLs that arise in AIDS patients are associated with latent EBV infections, whereas PCNSLs from immunocompetent patients are not indicating a probable role for EBV in pathogenesis of these tumors.

HTLV-I sequence in lymphoproliferative disorders

Several recent studies reported the detection of partially deleted HTLV-I provirus in biopsies of lesions from patients with mycosis fungoides (MF) and T-cell anaplastic large-cell lymphoma. We studied lesions from 59 patients (21 B-cell lymphomas: 16 diffuse and five follicular; 11 cutaneous T-cell lymphomas, including seven MF; one T-immunoblastic lymphoma; 10 diffuse anaplastic large-cell lymphomas: two B, four T, and four of indeterminate phenotype; three Hodgkin's lymphomas; eight atypical lymphoid proliferations; four other lymphoid lesions, and one squamous-cell carcinoma) using primers to the gag, pol and pX regions of HTLV-I in the polymerase chain reaction (PCR) to detect relevant sequences. A total of 10 patients showed one or more PCR-amplifiable products, including five of 11 patients with cutaneous T-cell lymphomas (45%) as compared with one of 21 patients with B-cell lymphomas (4.3%). We did not find a high incidence of positivity in anaplastic large-cell lymphomas, as reported previously. Detectable HTLV-I sequences were not limited to any subtype of lymphoma, and a pX sequence was detected in a squamous-cell carcinoma. Sequence analysis of one amplified product from each of the three regions studied showed a 94.2, 100, and 98.9% homology to the corresponding prototypical gag, pol, and pX HTLV-I sequences, respectively, indicating that the amplified sequences were derived from HTLV-I or a very closely related virus. HTLV-I sequences were detected in a significant proportion of patients with cutaneous T-cell lymphoma, but their role in the pathogenesis of the neoplasm is still unclear.

CHLVPP chemotherapy with involved-field irradiation for Hodgkin's disease: favorable results with acceptable toxicity

Patients with Hodgkin's disease who were previously untreated with chemotherapy received the chlorambucil, vinblastine, procarbazine, and prednisone (CHLVPP) regimen plus limited involved-field radiation therapy for treatment of Hodgkin's disease through the Nebraska Lymphoma Study Group. One hundred patients, 87 with newly diagnosed Hodgkin's disease and 13 who relapsed after receiving previous radiation therapy, were treated with this regimen between 1982 and 1989. Complete remissions (CRs) were obtained in 88 of 100 patients (88%), and there have been a total of eight relapses. The overall 3-year failure-free survival was 76%, with good-prognosis patients (ie, Karnofsky performance status greater than or equal to 80) having a 3-year failure-free survival of 87%. Toxicity with this regimen was minimal, with neutropenic fevers reported in 13% of the patient population, moderate alopecia in 5%, and mild to moderate nausea and vomiting in 11% of the patients. As primary induction therapy for Hodgkin's disease, CHLVPP is an effective regimen with a high patient acceptance profile.

Epstein-Barr viral genome in lymph nodes from patients with Hodgkin's disease may not be specific to Reed-Sternberg cells

A possible etiologic role for Epstein-Barr virus (EBV) in Hodgkin's disease (HD) was investigated by probing for EBV genome in 52 biopsy specimens involved with HD and 43 hyperplastic lymph node specimens. Using dot-blot hybridization (Bam HIW probe), Southern blot hybridization (Xho I probe), and polymerase chain reaction analyses, 27%, 27%, and 58% of the nodes with HD were positive for EBV genome, respectively, as compared to 16%, 14%, and 43% in the hyperplastic lymph nodes. Clonal and nonclonal episomal EBV and linear replicating EBV genome were present in both conditions. Immunoglobulin heavy chain gene rearrangements were found in two clonal and two nonclonal EBV-positive HD cases, but not in the lymphoid hyperplasia cases. These findings and other recent reports showing EBV genome in benign lymphoid cells by in situ hybridization in Hodgkin's disease suggest that the characteristics of EBV infection in HD could be explained by the reactive cellular milieu, especially in the setting of defective immunity. The identification of EBV genome in Reed-Sternberg cells may, therefore, be a nonspecific phenomenon.

Clinical significance of immunophenotype in diffuse aggressive non-Hodgkin's lymphoma

We performed a prospective study of the clinical significance of immunophenotype in 110 patients with aggressive non-Hodgkin's lymphoma (NHL) treated by oncologists in the Nebraska Lymphoma Study Group between October 1982 and May 1986. All patients were immunophenotyped from biopsies performed before therapy was administered. The patients were treated with a uniform protocol of radiotherapy for minimal nonbulky, stage I or II disease (seven patients) or a single, six-drug chemotherapy regimen cyclophosphamide, doxorubicin, procarbazine, bleomycin, vincristine, and prednisone (CAP-BOP) in patients with more extensive disease (103 patients). Ninety-one patients (83%) had B-cell lymphoma and 19 patients (17%) had T-cell lymphoma. The histologic diagnosis of diffuse mixed-cell lymphoma was significantly associated with T-cell immunophenotype (45% v 5%; P less than .001), and the diagnosis of diffuse large-cell lymphoma was significantly associated with B-cell immunophenotype (40% v 5%; P = .006). However, no significant difference in frequency of prognostic variables such as age, stage, systemic symptoms, tumor bulk, serum lactic dehydrogenase, or performance status was found between the B-cell and T-cell groups. Patients with B-cell NHL had a slightly higher complete remission rate (74% v 53%; P = NS), similar durability of complete remission (75% v 70% at 3 years; P = NS), and a slightly but not significantly better overall survival (50% v 41% at 3 years; P = NS). The slight advantage in response rate and survival for B-cell patients was related to a very poor outcome for patients with stage IV T-cell NHL. For patients with stage I to III disease, neither the complete remission rate (B-cell, 82% v T-cell, 91%; P = NS) nor overall survival (3-year survival for B cell, 58% v T cell, 73%; P = NS) were significantly different. However, with stage IV disease B-cell patients fared far better than those with T-cell NHL for both complete remission rate (67% v 0%; P = .002) and overall survival (3-year survival, 44% v 0%; P = .002). Immunophenotyping intermediate- and high-grade NHL allowed identification of a subgroup of patients who had a very poor prognosis with this treatment approach and for whom alternate therapy might be considered.

Allogeneic bone marrow transplantation in patients with lymphoma relapsing after autologous marrow transplantation

Two patients who underwent autologous bone marrow transplantation for recurrent non-Hodgkin's lymphoma relapsed at 46 and 28 days after the transplant. Both patients had an HLA-identical sibling and were treated with high-dose chemotherapy and allogeneic marrow transplantation. One patient is now 24 months after the allogeneic transplant without evidence of disease. The second patient died on day 7 with interstitial pneumonia. We conclude that high-dose therapy and allogeneic bone marrow transplantation after failure of autologous transplantation for non-Hodgkin's lymphoma is feasible and should be considered in young patients with HLA-identical siblings.

ChlVPP--an effective and well-tolerated alternative to MOPP therapy for Hodgkin's disease

The substitution of chlorambucil for nitrogen mustard and vinblastine for vincristine has been suggested to be an equally effective and well-tolerated variation of the MOPP regimen (mechlorethamine, vincristine, procarbazine, and prednisone). We treated 76 patients with advanced (i.e., Stage III, IV, or II with bulky mediastinal mass) or recurrent Hodgkin's disease with chlorambucil 6 mg/m2, procarbazine 100 mg/m2, and prednisone 40 mg p.o. daily, all on days 1-14; plus vinblastine 6 mg/m2 i.v. on day 1 and 8 of each 28-day cycle (ChlVPP). There was no maximum dose of the myelosuppressive agents. Patients who had not previously been irradiated received from 2,300 to 4,100 cGY to sites of previously bulky diseases after completing 6 cycles of ChlVPP. ChlVPP was easy to administer (i.e., 87% of patients without previous chemotherapy received greater than or equal to 80% of the planned doses of myelosuppressive drugs) and was generally well tolerated, with only occasional vomiting from procarbazine and phlebitis from vinblastine. In patients without previous chemotherapy, 49 (76%) achieved a complete remission (CR) and 7 (11%) a stable partial remission (i.e., residual, stable radiographic abnormality). With a maximum follow-up of 4 years, only one CR has relapsed for an actuarial CR durability of 97%. ChlVPP with consolidative radiation therapy to sites of bulky disease is effective in advanced Hodgkin's disease and, compared with most other available regimens, is extremely well tolerated.

Chromosomal abnormalities in indolent lymphoma

Cytogenetic studies were performed on lymph node biopsies from 60 patients with indolent (low grade) non-Hodgkin's lymphoma. Thirty-two of the 39 successfully cultured biopsies had abnormal clones. The 32 abnormal clones represented the following histologies: seven small lymphocytic lymphoma (SL), eight follicular small cleaved cell lymphoma (FSC), 14 follicular mixed, small cleaved, and large cell lymphoma (FM), and three composite lymphomas. One of the composite lymphomas had FSC/DSC (diffuse small cleaved cell) and the other two FM/DM (diffuse mixed, small cleaved and large cell). Twenty-seven of the 32 biopsies were immunologically typed, and all were B cell. The clones all exhibited more structural than numerical abnormalities, and there was no difference in the modal chromosome number of the abnormal clones found in each histology. Biopsies with no normal cells were more frequently found in the SL histology (71%) than in the two follicular lymphoma groups (54%-55%). A translocation of the 14q32 segment was the most common abnormality found in all three histologies. In the follicular lymphomas a t(14;18)(q32;q21) was seen in 52% (13 of 25) of these patients, this translocation was not observed in the SL patients. Overall 84% (21 of 25) of the follicular lymphoma patients had abnormalities of 14q32 and/or 18q21. Other specific abnormalities included anomalies of chromosome #3 in FM, an abnormal 10q in FSC and FM lymphoma, and a high incidence of +18 and chromosome #1 abnormalities in patients with t(14;18). The presence of specific chromosome abnormalities in the indolent lymphoma patients suggests a relationship between certain karyotypic features and histology.

The role of monocytes in serum sickness nephritis

We have investigated the pathogenesis of glomerular hypercellularity seen in acute serum sickness nephritis induced in rabbits with bovine serum albumin (BSA). The increase in cellularity began with the first stages of immune clearance of BSA, with a peak cellularity occuring at the time of onset of proteinuria. Although there was a significant increase in the fraction of glomerular cells incorporating [3H]thymidine, first seen at the onset of proteinuria, this increase occurred too late and was too small to explain the observed rate of increase in glomerular cellularity. On the other hand, a striking monocytic infiltration of the glomeruli was documented by electron microscopy and by staining for nonspecific esterase. This monocytic infiltration paralleled the observed course of glomerular hypercellularity and was quantitatively sufficient to explain the total increase seen. It appears, therefore, that glomerular hypercellularity seen in this model is principally a result of monocyte infiltration.

Immunoblastic lymphadenopathy with pulmonary infiltrates, hypocomplementemia and vasculitis. A hyperimmune syndrome

A detailed description of the clinical and morphologic characteristics of four patients with immunoblastic lymphadenopathy, pulmonary infiltrates, hypocomplementemia and vasculitis is presented. Noteworthy in the patients described here is the clinical similarity to patients with collagen-vascular diseases and systemic drug reactions. The frequent occurrence of pulmonary symptoms, bilateral interstitial infiltrates and pleural effusions is emphasized. The morphology suggests stimulation of the immune system by antigenic agents, and the low complement levels and the presence of vasculitis suggest that circulating immune complexes may be present. Immunoblastic lymphadenopathy may represent a syndrome in which the adenopathy is but a nonspecific part of a systemic hyperimmune response to unknown antigens. The clinical course of the patients reviewed suggests that supportive treatment and corticosteroids constitute the safest therapeutic approach.