Diffuse intermediate lymphocytic lymphoma. A clinicopathologic study and comparison with small lymphocytic lymphoma and diffuse small cleaved cell lymphoma

Controversy has recently arisen as to whether diffuse intermediate lymphocytic lymphoma (ILL) should be considered a low-grade or an intermediate-grade non-Hodgkin's lymphoma for clinical purposes. Therefore, the authors performed a clinicopathologic study to determine the biologic course of diffuse ILL (40 cases) and compared it with small lymphocytic lymphoma (SLL; 51 cases) and diffuse small cleaved cell lymphoma (DSCCL; 14 cases). They found that patients with diffuse ILL having pseudofollicular proliferation centers (PC) had a significantly longer median survival (84 months) than those without PC (46.5 months; P = 0.03). The median survival of patients with SLL was 72 months, whereas those with DSCCL had a median survival of only 18 months. Based on these findings, the authors conclude that diffuse ILL with PC should be included in the low-grade category of SLL for clinical purposes, whereas diffuse ILL without PC (true diffuse ILL) should be considered an intermediate-grade non-Hodgkin's lymphoma. True diffuse ILL is similar to centrocytic lymphoma in the Kiel classification and should be accorded a similar status in a modified Working Formulation.     

Establishment of a novel B-lymphoma cell line, CTB-1, with strong Pas antigen expression having chromosomal translocation (14;22)

We established a new lymphoma cell line, designated CTB-1, from pericardial effusion of a patient with diffuse large B-cell lymphoma. This cell line showing vigorous growth ability has undergone 260 passages over a period of 34 months in suspension culture, and is heterotransplantable to nude mice. The cultured cells were positive for CD10, CD19, CD20, CD21, HLA-DR, and surface IgG kappa, and negative for T cell antigens. Chromosomal analysis revealed a t(14;22)(q32;q11) that is consistent with original lymphoma cells. CTB-1 cells show the high cell surface expression level of Fas antigen/APO-1. However, ligation of Fas antigen with anti-Fas monoclonal antibody (clone CH-11) did not induce apoptosis of CTB-1 cells. This suggests that Fas itself or the downstream signaling pathways of Fas may be impaired in this cell line. This new cell line may provide a useful in vitro system to study the biology and pathogenesis of B-cell lymphoma which is independent of Fas-mediated apoptosis.     

HLA-DR protein status predicts survival in patients with diffuse large B-cell lymphoma treated on the MACOP-B chemotherapy regimen

Loss of major histocompatibility class II (MHC class II) molecules on diffuse large B-cell lymphoma (DLBCL) has been associated with poor survival; however, none of these reports analysed a uniformly treated patient cohort. This study was designed to validate one MHC class II antigen, HLA-DR, as a prognostic marker in patients uniformly treated with the MACOP-B regimen. Immunostaining results were correlated with the international prognostic index (IPI) score and overall survival (OS). Of the 97 cases, 82 had interpretable staining. Of these, 52 expressed HLA-DR (median OS, 16.2 years) while 30 were negative (median OS, 4.2 years, P = 0.037). The IPI was also predictive of OS in the study group (P = 0.023). A Cox multivariate model established both IPI (P = 0.031) and HLA-DR (P = 0.04) as independent predictors of OS. This is the first demonstration of the prognostic relevance of HLA-DR in a uniformly treated DLBCL patient group.     

Malignant lymphomas of follicular center cell origin in man. VI. Large cleaved cell lymphoma

Between 1970 and 1986 61 patients with large cleaved cell lymphoma (LCCL) were observed and treated. Median age was 56, and there were slightly more women than men (ratio, 1.4:1). Forty-four cases (72%) had both a nodular and diffuse pattern; eight cases were nodular; nine cases were diffuse. Forty-three patients (70%) had Stage III or IV disease; four patients were Stage I (7%); 14 were Stage II (23%). Bone marrow was involved in 15 of 56 evaluable patients (27%). The median survival was 57 months. It was significantly shorter in symptomatic patients (median, 20 months) than in asymptomatic patients (median, 66 months; P = 0.002). Survival time was also shorter in Stage III and IV patients (median, 46 months) compared with Stage I and II patients (median, 100+ months; P = 0.032). Survival was independent of the disease pattern, marrow involvement, age, gender, and surface immunoglobulin heavy or light chain. Among Stage III and IV patients, survival was the same in patients who received therapy initially and in those who were treated expectantly. Among 10 advanced-stage patients who did not initially receive therapy, the median time to beginning therapy was 17 months; five patients received no therapy for 40 to 96 months. Among 14 advanced-stage patients receiving therapy regarded as curative in aggressive lymphoma, 50% experienced a complete remission (CR). However, unlike other aggressive large cell lymphomas, long-term, relapse-free survival was observed in only 9% of patients as the majority of CRs were associated with relapse rather than cure. Despite the fact that it is a large cell lymphoma, LCCL is best regarded as an indolent lymphoma.     

Cyclin D3 is a predictive and prognostic factor in diffuse large B-cell lymphoma.

Cyclin D3 is an important regulator for transition from G(1) to the S phase of the cell cycle. Cyclin D3 expression is associated with cell proliferation in lymphoid tissues, but its impact on clinical outcome in non-Hodgkin's lymphomas has not been studied. Therefore, we determined the clinical relevance of cyclin D3 expression in patients with diffuse large B-cell lymphoma. We examined the relation between cyclin D3 expression at diagnosis and response to conventional polychemotherapy and overall survival in 81 previously untreated patients with diffuse large B-cell lymphoma. Cyclin D3 expression was assessed by immunohistochemistry. Cyclin D3 immunostaining ranged from 0-100% (median, 30%) of the lymphoma cells. Patients with high (>or=50% cyclin D3-positive lymphoma cells) cyclin D3 expression had a more advanced clinical stage (P = 0.003) and more often had extranodal disease in more than one site (P = 0.007) than patients with low cyclin D3 expression. Patients with high cyclin D3 expression had a significantly lower complete response rate (17% versus 74%; P < 0.001) and a shorter overall survival (3-year survival rate, 18% versus 74%; P < 0.001) than those with low cyclin D3 expression. Multivariate analyses that included cyclin D3 and the International Prognostic Index demonstrated that cyclin D3 expression had independent effects on the complete response rates and overall survival of the patients. In conclusion, high cyclin D3 expression is an independent predictive and prognostic factor associated with poor clinical outcome in patients with diffuse large B-cell lymphoma.     

Ki-1 antigen expression defines a favorable clinical subset of non-B cell non-Hodgkin's lymphoma

Immunohistochemical and immunophenotypic analyses were performed on 278 cases of karyotypically abnormal non-Hodgkin's lymphoma (NHL). Excluding cases of lymphoblastic lymphoma or mycosis fungoides, 20 cases showed evidence of non-B cell lineage. T cell lineage was proven by genotypic and immunophenotypic analyses in 15 of the 20 cases; five were of ambiguous lineage. All of the non-B lineage cases were of diffuse histology with a large cell component (DLCL). Twelve cases expressed the Ki-1 antigen; five of these cases also demonstrated a translocation with a break at 5q35. Patients with Ki-1 positive DLCL and t(5q35) had a younger median age compared with non-B cell DLCL without t(5q35). The Ki-1 positive patients had a higher frequency of skin involvement and lower incidence of bone marrow involvement compared with Ki-1 negative DLCL. Survival analysis was performed on 86 cases of B cell DLCL and 18 cases of non-B cell DLCL which were serially ascertained prior to receiving cytotoxic chemotherapy. Median duration of complete remission was significantly longer in the B cell compared with the non-B cell DLCL groups; there was only a trend for decreased overall survival in the non-B cell group. Among the subset of non-B cell lymphomas, overall survival of patients with Ki-1 expressing DLCL was significantly longer than those with Ki-1 negative DLCL, who had a median survival of less than a year. These results show that immunophenotypic, immunohistochemical, and cytogenetic markers can define subsets of patients with non-B cell lymphomas with differing clinical characteristics and outcome.     

Diffuse large cell lymphoma with discordant bone marrow histology. Clinical features and biological implications

In patients with diffuse large cell lymphoma (LCL), bone marrow involvement at the time of diagnosis is a poor prognostic sign. Since 1980, the authors have encountered 13 patients LCL who had simultaneous bone marrow involvement by small cleaved cell lymphoma (11 cases) or mixed small and LCL (two cases), a phenomenon known as "discordant" or "divergent" bone marrow histology. The patients ranged in age from 33 to 85 years (median, 61 years) and presented most commonly with Stage III or IV disease, independent of bone marrow involvement. Seventy-seven percent achieved complete remission (CR) with combination chemotherapy; 50% of these eventually relapsed and died of their disease. One patient died of unrelated causes. No recurrences of low-grade lymphoma were observed, as judged either by clinical behavior or rebiopsy. The survival of the patients with discordant bone marrow histology was compared with that of patients with LCL with or without bone marrow involvement by LCL. Of the 11 patients with discordant marrow histology followed for a minimum of 2 years, four (36%) are long-term survivors; this is comparable to the 2-year survival of patients with LCL without bone marrow involvement (45%). In contrast, 89% of patients with bone marrow biopsy specimens positive for LCL died within 18 months from the time of diagnosis (mean survival, 5.7 months). All diffuse LCL tested were of B-lineage. The authors attempted to determine whether the presence of discordant bone marrow histologic types indicated an underlying low-grade B-cell lymphoma in these patients by evaluating the peripheral blood of the long-term survivors for the presence of clonal excess. Of the three surviving evaluable patients tested, one had evidence of clonal excess in the peripheral blood. For patients with LCL who have a simultaneous bone marrow biopsy positive for low-grade lymphoma (discordant marrow histology), survival is no different from that of patients with negative marrows, and markedly better than that for patients with marrows positive for diffuse LCL. The biological significance of discordant bone marrow histology is not clear at this time.     

Establishment of Epstein-Barr virus-negative diffuse large cell lymphoma cell line with an 8;22 chromosomal translocation

A new human B-cell lymphoma cell line was established from a pleural effusion of a patient with a diffuse large cell lymphoma which originated from an ileocecal tumor. The cell line, designated KAL-1, has been passaged 280 times over a period of 22 months. This cell line was successfully maintained in a chemically defined serum-free medium; its doubling time is approximately 24 h. Immunologically, the cells were demonstrated to express IgM lambda on the cell surface and to react with monoclonal antibodies to B-cell antigen including B1, B4, HLA-DR, and common acute lymphoblastic leukemic antigen but not with B2 and all the T-cell markers. Immunoglobulin gene analysis revealed rearrangements of both JH and C lambda. These data indicate that this cell line represents the B-cell lineage at the immature B-cell stage. This cell line was negative for Epstein-Barr virus nuclear antigen and had no detectable Epstein-Barr virus genome in cellular DNA. Chromosome analyses revealed that the cells carried an 8;22 chromosome translocation, reminiscent of variant type Burkitt's lymphoma. However, there was no histological evidence for Burkitt's lymphoma. Molecular studies showed that KAL-1 had deregulated high constitutive expression of c-myc. This cell line was demonstrated to be highly tumorigenic when injected into athymic nude mice. This tumor model should provide clues about the molecular mechanism involved in the pathogenesis of B-cell malignancy and appears to be a useful in vivo model for the study of molecular events during B-cell differentiation and therapeutic investigations.     

弥漫大B细胞淋巴瘤中PTEN蛋白表达的临床意义

 目的　研究PTEN蛋白在弥漫大B细胞淋巴瘤（DLBCL）中的表达情况,探讨PTEN蛋白表达与DLBCL预后的关系。方法　采用免疫组化方法检测40例原发结内DLBCL患者肿瘤组织中PTEN蛋白的表达情况。应用Kaplan-Merie生存分析、Log-Rank差异显著性检验和Logistic回归分析进行统计学分析。结果　PTEN蛋白阳性组16例,阴性组24例。PTEN蛋白阳性组和阴性组患者的2年总体生存率差异无统计学意义（57.7 %比62.5 %,P >0.05）,两组患者的生存率随时间的延长均逐渐减低,PTEN阳性组的生存率低于阴性组,但两组的生存曲线差异无统计学意义（P >0.05）。PTEN蛋白表达与DLBCL分子分型无相关性（P >0.05）。PTEN蛋白表达与患者年龄、体力状态、病情分期、乳酸脱氢酶（LDH）及结外受侵无相关性（P >0.05）,回归分析表明,DLBCL中PTEN蛋白表达不是疾病的保护因素,国际预后指数（IPI）是疾病的危险因素（OR＞1）。此外,PTEN蛋白细胞核表达占15 %（6／40）,核表达的例数在PTEN蛋白表达阳性组和阴性组间差异无统计学意义（1∶1）。结论　DLBCL中PTEN蛋白表达高低与预后无相关性,IPI仍是判断其预后的指标。     

Expression of Hla-Class II Antigen in Gastric Carcinomas: Its relationship to histopathological grade, lymphocyte infiltration and five-year survival rate

To investigate whether the expression of HLA-DR antigen in gastric carcinomas is associated with the survival rate, we studied 70 cases of gastric carcinoma using a monoclonal antibody. Forty-seven cases (67%) stained positively, including 31 differentiated carcinomas, and 16 undifferentiated carcinomas. A close correlation was found between expression of HLA-DR antigen and differentiation of the tumor cells. Marked lymphocyte infiltration was seen in the HLA-DR antigen positive cancers. In advanced gastric cancers, the 5-year survival rate of patients with HLA-DR antigen positive cancers was significantly higher (67.5%) than that of patients with HLA-DR antigen negative cancers (40%). The data suggest that the expression of HLA-DR antigen in gastric carcinomas may reflect the degree of tumor cell differentiation, and influence the host immune response and prognosis.     

Multidrug resistance (MDR-1) expression in AIDS-related lymphomas.

P-glycoprotein is a product of the multidrug resistance (MDR-1) gene. In non-Hodgkin's lymphoma, less than 20% of untreated de novo lymphomas express MDR-1 compared with approximately 50% after failure of chemotherapy. We wished to study the expression of MDR-1 in AIDS-related non-Hodgkin's lymphoma (AIDS-NHL). Tissue biopsies from 50 patients with newly diagnosed AIDS-NHL were studied by immunohistochemical analysis using C494, a monoclonal antibody specific for the MDR-1 isoform of P-gp. MDR-1 expression was correlated with patient demographics, lymphoma characteristics, response to chemotherapy, and survival. Forty-six males and four females with a median age of 38 years (range 26-63) were studied. A prior AIDS-defining opportunistic infection was reported in 35 patients (70%). The median CD4+ lymphocyte count was 69/mm(3) (range 0-920). Thirty-two patients (63%) had received prior anti-HIV therapy, including a protease inhibitor in five (10%). Pathologic types consisted of diffuse large cell in 13 (26%), immunoblastic in 13 (26%), small non-cleaved in 22 (44%), and high grade not otherwise specified in two (4%). The majority of patients (76%) had stage III/IV disease. Pre-treatment lymphoma tissues from 33 patients (66%) stained positively for MDR-1. MDR-1 positive patients had a significantly lower complete remission rate compared to MDR-1 negative patients (33 versus 65%, P=0.042). Duration of complete response was significantly longer in MDR-1 negative patients compared with MDR-1 positive patients (not reached versus 9.9 months, P=0.003). Strategies to overcome MDR-1 expression may be important for initial treatment in patients with AIDS-NHL.     

儿童系统性EB病毒阳性T细胞淋巴组织增殖性疾病临床病理分析

目的 探讨儿童系统性EB病毒阳性T细胞淋巴组织增殖性疾病(CSEBV+T-LPD)的临床病理特征及免疫表型.方法 通过免疫组织化学、原位杂交、基因重排技术,分析11例CSEBV+T-LPD患者临床病理特征,并进行随访.结果 临床特征:男性5例,女性6例,中位年龄13岁(3~19岁),中位病程6个月(3~25个月).其中4例诊断为淋巴瘤,男女各2例,中位年龄15岁,中位病程4.5个月.11例患者主要症状有反复持续发热(10例)、多发淋巴结肿大(10例)、脾大(7例)、肝大(4例).组织病理学特征:4例淋巴瘤患者表现为淋巴细胞片状或弥漫性增生,细胞体积中等偏大,增生细胞较单一;7例良性病变者增生细胞较混杂,增生淋巴细胞散在其中,体积中等偏大或大.免疫表型:全部患者增生细胞大多数为T细胞,均强弱不等地表达CD3ε.2例淋巴瘤患者、1例良性病变者中CD8单阳性,4例淋巴瘤患者、1例良性病变者有T细胞抗原丢失.全部患者EBV-EBER阳性.T细胞受体(TCR)基因检测:3例淋巴瘤患者、1例良性病变者检测到克隆性重排.病理分级:淋巴瘤患者均为A3级,良性病变者1例为A2级、6例为A1级.结论 CSEBV+T-LPD是一系列涵盖不同发展阶段的疾病谱,诊断需结合临床特征、病理形态、免疫表型、EBV-EBER原位杂交及TCR基因检测等综合分析.患者年龄偏大,增生细胞较单一、 弥漫或片状,CD8单阳性,T细胞抗原丢失尤其CD5、EBV-EBER高表达,TCR克隆性重排,病理分级为A3级等因素对于鉴别良、恶性病变可能有重要提示意义.     

Lennert's lymphoma. A clinicopathologic study with emphasis on phenotype and its relationship to survival

In this report we describe the results of a clinical and immunohistochemical analysis of 11 consecutive patients with the specific clinicopathologic entity of Lennert's lymphoma (non-Hodgkin's malignant lymphoma with a multifocal epithelioid histiocytic reaction [MLEH]) evaluated at the Arizona Cancer Center. Detailed immunophenotyping of ten patients showed that seven patients (73%) had an activated "novel" T-cell phenotype, indicative of peripheral T cell lymphoma (PTL). Additionally, six of these seven PTL patients had T-helper (Leu-3) antigen expression to the exclusion of T-suppressor (Leu-2) expression. Three patients, in complete contrast, had a B-cell lymphoma with monoclonal immunoglobulin expression. The B-cell MLEH were morphologically indistinguishable from T-cell MLEH. Clinically, the initial diagnosis proved difficult; ten of the 11 patients were initially misdiagnosed, most often as another lymphoid disorder or as granulomatous disease (mean delay of 10 months in diagnosis from onset of symptoms). The median survival of all patients was 20 months (1 to 45+ months) with two apparent subgroups: those who had rapid progression of disease with a median survival of 5 months, all of T-cell phenotype; and a small group whose median survival has not yet been reached, all of B-cell phenotype. Our results suggest that the immunophenotype, B-cell versus T-cell, may be a major predictor of survival, with B-cell MLEH patients having a longer survival than those of T-cell type.     

HLA-DR antigen and bax protein expression in patients with primary non-Hodgkin's gastric lymphoma

Primary gastric lymphoma represents a rare gastrointestinal malignancy with an unclear prognosis. The aim of this study was to determine the prognostic significance of HLA-DR antigen and bax expression in patients with primary non-Hodgkin's gastric lymphoma. We immunohistochemically studied bax protein and HLA-DR antigen expression in 36 B-cell, MALT-type primary gastric lymphoma patients diagnosed and treated in our department from 1990 to 1995. Ten non-malignant gastric tissue specimens were used as benign controls. Clinicopathological and survival data were correlated with the staining results. HLA-DR antigen expression was observed in 33 gastric lymphoma patients (91.7%). Positive bax staining was found in 24 gastric lymphomas (66.7%) and in none of the benign cases studied. In the univariate analysis, those gastric lymphoma patients who expressed HLA-DR antigen in more than 15% of their tumor cells, presented a significantly improved 5-year survival rate (75% vs. 37.5%, p = 0.04). Furthermore, gastric lymphoma patients who were bax(+)/HLA-DR(+) had a statistically better overall survival compared to those who were bax(-)/HLA-DR(-) (82.4% vs. 25%, p = 0.01). HLA-DR antigen expression was associated with a favorable clinical outcome. Its expression improved the predictive value of bax protein expression in non-Hodgkin's gastric lymphoma patients. The combined use of these markers permits the identification of a high-risk group of patients that may benefit from a more aggressive therapeutic approach.     

Histopathologic, immunophenotypic, and genotypic analysis of Ki-1 anaplastic large cell lymphomas that express histiocyte-associated antigens

CD30/Ki-1 antigen expression in 243 cases of malignant lymphomas was examined using Ber-H2 monoclonal antibody. Among them 20 cases were categorized as Ki-1 anaplastic large cell lymphoma. In two of these cases histiocyte-associated markers were also expressed. In these cases histopathologic and extensive in situ immunophenotypic analyses were used with genotypic studies in the determination of cell lineage. A sinusoid histologic pattern of involvement with partial lymph node infiltration by pleomorphic neoplastic cells was noticed in the nodes from both patients. Solid areas of node replacement resembling metastatic carcinoma were seen in Patient 1. Immunohistologically, tumor cells of both cases were positive for CD30, CD25, CD71, LN3 (HLA-DR), EMA, CD45, CD74, vimentin, alpha-1-antichymotrypsin, and CD68. Patient 1 was also CD45RO+, CD43+, whereas Patient 2 was positive for alpha-1-antitrypsin and CD4 tumor cells. Genotypic studies revealed that TCR beta and TCR gamma chain genes were clonally rearranged in Patient 1, whereas no rearrangements were detected in Patient 2. This study supports the view that some Ki-1 anaplastic large cell lymphomas may express multiple histiocyte-associated antigens and confirms that this group of neoplasms have immunophenotypic heterogeneity. The results of genotypic analyses used with immunophenotyping does not exclude that the tumor cells in these cases may be of true histiocytic origin despite the Ki-1-positive phenotype.     

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.     

Liposomal encapsulated doxorubicin (Caelyx) in the treatment of relapsed aggressive non-Hodgkin's lymphoma: a phase II study

Aggressive non-Hodgkin's lymphoma (NHL), such as diffuse large B-cell lymphoma, can be cured in approximately 50% of cases, but those cases that recur and are not amenable to high-dose chemotherapy rely on palliative chemotherapy to improve symptoms and prolong life. Anthracyclines are associated with a high response rate in aggressive NHL but extended treatment results in cardiotoxicity. Liposomal encapsulated doxorubicin has been shown in other tumor types to allow for extended treatment with doxorubicin, but is associated with a low cardiac risk. The present study aimed to assess the response rate, survival and cardiac risk of patients with relapsed aggressive NHL treated with liposomal encapsulated doxorubicin. Eighteen patients with relapsed aggressive NHL were treated with liposomal encapsulated doxorubicin (40 - 50 mg/m2) for a planned six cycles. Some 83% of patients had diffuse large B-cell or mantle cell NHL. Four patients had a partial response (23%), whereas five patients had stable disease. None had a complete response. Eight patients progressed when receiving the liposomal encapsulated doxorubicin therapy. The median survival time was 34 weeks, and the median progression-free survival was 15.7 weeks. Overall survival was 50% at 6 months and 39% at 12 months. Progression-free survival was 33% at 6 months and was 28% at 12 months. The mean ejection fraction pre- and post-liposomal encapsulated doxorubicin treatment remained the same. Only one patient had a drop in ejection fraction to <50%. Liposomal encapsulated doxorubicin offers another choice to patients seeking palliation from their lymphoma recurrence with a response rate of 23% that was well tolerated and had a minimal cardiotoxic risk.     

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.     

Childhood malignant non-Hodgkin lymphomas of uncommon histology.

Uncommon histologies were identified in 36 of 1336 cases (2.7%) of newly diagnosed childhood non-Hodgkin lymphoma (NHL). Seventeen cases were classified as follicular (six cases as mixed small and large cell, nine as large cell, and two as small non-cleaved cell) and 19 cases as diffuse (18 cases as mixed small and large cell, and one as small cell lymphocytic). The follicular pattern group included a preponderance of male patients; the median age at diagnosis was 11.7 years. These children presented primarily with low-stage disease involving lymph nodes or tonsils. All patients except one achieved complete remission and remain disease-free for 11 months to 18.8 years (actuarial 5-year event-free survival, 94%). The group with diffuse histologies was similar in sex ratio, age at diagnosis (median = 12.1 years), and nodal involvement, but tended to have more advanced-stage disease. Moreover, only 14 of 19 (74%) children with diffuse intermediate-grade histologies are alive in continuous complete remission (actuarial 5-year event-free survival, 70%). These results suggest that follicular pattern childhood NHL has an excellent prognosis, whereas cases with diffuse intermediate-grade histology are prognostically similar to those with diffuse high-grade histologies.