Expression of serotherapy target antigens in Waldenstrom's macroglobulinemia: therapeutic applications and considerations

Monoclonal antibody (mAb) therapy (serotherapy) has been successfully used in the treatment of many B-cell malignancies, among them lymphoplasmacytic lymphoma, an uncommon disorder that includes patients with the clinicopathological diagnosis of Waldenstrom's macroglobulinemia (WM). Rituximab, a mAb directed at CD20, was recently demonstrated by us and others to induce remissions and facilitate hematological recovery in patients with WM. The expression of CD20, along with targets of other mAbs which are commercially available, currently in clinical trials, or in preclinical development, have not been extensively studied or well documented in lymphoplasmacytic lymphoma. As such, we examined by flow cytometric analysis tumor cells from a large series of patients with the histopathlogical diagnosis of lymphoplasmacytic lymphoma and the clinicopathological diagnosis of WM for expression of the serotherapy target antigens CD20, CD22, CD40, CD52, IgM, MUC1 core protein, and 1D10. These studies demonstrated antigen expression on >or=50% of bone marrow tumor cells (CD19(+), kappa/lambda light chain-restricted), respectively, from patients as follows: CD20 (98.3%), CD22 (88.3%), CD40 (83.3%), CD52 (77.4%), IgM (83.3%), MUC1 core protein (57.8%), and 1D10 (50%). Both interpatient and intrapatient tumor clone antigen expression was heterogeneous. Combined mAb therapy might be a useful approach to cope with this variation, and could be tailored to target all members of the tumor clone for an individual patient.     

Characterization of familial Waldenstrom's macroglobulinemia.

BackgroundFamilial clustering of B-cell disorders among Waldenström's macroglobulinemia (WM) patients has been reported, though the frequency and any differences in disease manifestation for familial patients remain to be defined.Patients and methodsWe therefore analyzed clinicopathological data from 257 consecutive and unrelated WM patients. Forty-eight (18.7%) patients had at least one first-degree relative with either WM (n = 13, 5.1%), or another B-cell disorder including non-Hodgkin's lymphoma (n = 9, 3.5%), myeloma (n = 8, 3.1%), chronic lymphocytic leukemia (n = 7, 2.7%), monoclonal gammopathy of unknown significance (n = 5, 1.9%), acute lymphocytic leukemia (n = 3, 1.2%) and Hodgkin's disease (n = 3, 1.2%). Patients with a familial history of WM or a plasma cell disorder (PCD) were diagnosed at a younger age and with greater bone marrow involvement.ResultsDeletions in 6q represented the only recurrent structural chromosomal abnormality and were found in 13% of patients, all non-familial cases. Interphase FISH analysis demonstrated deletions in 6q21-22.1 in nearly half of patients, irrespective of familial background.ConclusionsThe above results suggest a high degree of clustering for B-cell disorders among first-degree relatives of patients with WM, along with distinct clinical features at presentation based on familial disease cluster patterns. Genomic studies to delineate genetic predisposition to WM are underway.     

Despite apparent morphologic and immunophenotypic heterogeneity,Waldenstrom's macroglobulinemia is consistently composed of cells along a morphologic continuum of small lymphocytes,plasmacytoid lymphocytes,and plasma cells

We studied the clinical, morphologic, and immunophenotypic features of 26 Waldenstrom's macroglobulinemia (WM) cases, each with an IgM spike of >or=3.0 g/dL. The neoplastic cells were consistently composed of a spectrum of small lymphocytes, plasmacytoid lymphocytes, and plasma cells. Bone marrow (BM) involvement ranged from 10% to 90%, showed four histologic patterns (nodular [75%], interstitial [75%], paratrabecular [42%], and diffuse [4%]), two histologic subtypes (lymphoplasmacytic [87%] and lymphoplasmacytoid [13%]), and several cytologic variants (monocytoid [n = 2], signet-ring cell [n = 2], and hairy cell leukemia-like [n = 1]). By flow cytometry (FC), all cases expressed monoclonal surface immunoglobulin, CD19, and CD20. Most cases (58%) lacked expression of CD5, CD10, and CD23. However, variants such as CD5(+)CD10(-)CD23(-) (n = 3), CD5(+)CD10(-)CD23(+) (n = 1), and CD5(-)CD10(+)CD23(+/-) (n = 2) were seen. At last follow-up, 18 of 26 patients were alive (median survival, 94 months). Causes of death included WM (n = 1), large cell lymphoma (n = 1), acute myeloid leukemia (likely therapy-related [n =2]), and nonhematologic/unknown. When individual WM cases are compared, apparent morphologic diversity is suggested. However, every WM case is comprised of cells along a morphologic continuum from small lymphocytes to plasma cells, delineating a uniform, consistent pathology. As WM shows immunophenotypic heterogeneity, morphology must be the cornerstone of the diagnosis.     

The clinical and diagnostic relevance of CD23 expression in the chronic lymphoproliferative disease

BACKGROUND: CD23 antigen is a cell surface protein considered important in the differentiation of chronic lymphocytic leukemia (CLL) from other lymphoid leukemias. METHODS: To better clarify CD23 role as a diagnostic tool, the authors retrospectively evaluated clinical and laboratory features of 372 patients who were referred to M.D. Anderson Cancer Center with a diagnosis of CLL or B-cell chronic lymphoproliferative disease. RESULTS: Most of the patients (91%) were CD19+/CD5+. Only 6% of these CD19+/CD5+ patients were CD23-. Overall, CD23- patients had the worse prognostic features compared with CD23+ cases, including anemia (P = 0.03), massive splenomegaly (P = 0.000), high lactate dehydrogenase (P = 0.007), high beta2-microglobulin (P = 0.006), older age (P = 0.001), and male gender (P = 0.02). Surface immunoglobulin expression was moderate/strong in 19 (82%) patients, and FMC-7 was positive in 22 (96%) patients. None of the 13 patients tested for CD10 expressed the antigen. Based on morphology, of the CD23, 16 (70%) were diagnosed with mantle cell leukemia (MCL) was diagnosed in 16 (70%) CD23- patients, 3 (13%) with splenic marginal-zone leukemia, 3 (13%) with prolymphocytic leukemia (PLL) or PLL/CLL, and 1 (4%) with CLL. No cyclin D1 protein expression was noted by Western blot analysis in the one case that showed typical CLL morphology, and this patient did not require therapy. On the whole, the survival rate of CD23- patients was significantly worse than that of patients with CD23+. In contrast, 15 of 32 (49%) CD19+/CD5- patients were CD23-. CD23 negativity in this group was not associated with distinct clinical features or outcome. Eleven (73%) of these patients were classified as having splenic marginal-zone lymphoma and 4 as having follicular lymphoma. CONCLUSIONS: These data indicate that CD23 negativity is rare in typical B-cell CLL, and CD23 negativity in patients with CD19+/CD5+ is suggestive of mantle cell leukemia a more aggressive disease with poor response to conventional therapy in which newer chemotherapy regimens such as hyper-CVAD may be more effective.     

CD52 expression in Waldenstrom's macroglobulinemia: implications for alemtuzumab therapy and response assessment

The efficacy of monoclonal antibody therapy is determined, at least in part, by the extent to which the target antigen is expressed. This is a complex issue in Waldenstrom's macroglobulinemia (WM) as it is a disorder characterized by plasma cell differentiation and therefore target antigen expression may differ between the B-cell and plasma cell compartments of the disease. In order to assess this in the context of alemtuzumab therapy, the authors used multiparameter flow cytometry to determine CD52 expression in the B-cells and plasma cells of patients with WM. CD52 expression was demonstrable in the B-cells of all cases, with a median of 99% of cells (range, 81%-100%) expressing the antigen compared with the isotype control (n = 47). Antigen density was very similar to that seen in chronic lymphocytic leukemia (median mean fluorescence intensity [MFI], 1249; range, 175-3170). Antigen expression was, however, significantly lower in the plasma cells (median MFI, 235; range, 31-1814) in all but 1 of the cases assessed (n = 21). The clinical significance of this was assessed by examining serial bone marrow samples from patients receiving alemtuzumab as part of an ongoing clinical trial. In 4 of 5 patients, alemtuzumab therapy successfully eradicated clonal B-cells from the bone marrow, but residual plasma cells remained evident in 2 of these patients. The implications of these findings for monoclonal antibody therapy in WM are discussed.     

淋巴浆细胞性淋巴瘤/华氏巨球蛋白血症10例临床病理学特征分析及MYD88基因突变检测

背景与目的：淋巴浆细胞性淋巴瘤/华氏巨球蛋白血症（lymphoplasmacytic lymphoma/Waldenström macroglobulinemia,LPL/WM）是罕见的B细胞惰性淋巴瘤,其诊断常需要与其他小B细胞性肿瘤作鉴别。本研究皆在探讨LPL/WM的临床病理学特点,并观察MYD88基因突变在此类肿瘤中的检出频率。方法：分析10例LPL/WM病例的临床资料、组织学形态和免疫组织化学表型,并以聚合酶链反应（polymerase chain reaction,PCR）扩增及直接测序法检测肿瘤标本MYD88基因的状态。结果：10例患者均为男性,中位年龄61岁。患者多表现为乏力和贫血,均有不同程度的IgM型免疫球蛋白血症和肿瘤骨髓累及。淋巴结活检标本光镜检查显示淋巴结结构部分存在,特别是可以见到开放的淋巴窦。肿瘤由数量不等的浆细胞、小淋巴细胞及浆样淋巴细胞组成。骨髓活检标本也可见到相同形态的细胞浸润。免疫组织化学染色显示,10例肿瘤细胞均呈CD20弥漫阳性并限制性表达免疫球蛋白轻链κ,6例瘤细胞表达CD23,2例部分瘤细胞表达CD5,未见病例表达CD10,Ki-67增殖指数在5%~30%之间。另外,2例LPL/WM在其病灶中尚可见到较多的IgG4阳性反应性浆细胞浸润。所有LPL/WM病例肿瘤组织均有MYD88 L265P突变检出,而对照组其他小B细胞性肿瘤均为阴性结果。结论：LPL/WM多具有典型的临床病理学形态,但偶亦可出现异常表型。MYD88 L265P作为LPL/WM的特征性遗传学特点,其检测的引入可使此类肿瘤的诊断和鉴别有更可靠的依据。     

Differential diagnosis of Waldenstrom's macroglobulinemia from other low-grade B-cell lymphoproliferative disorders

Waldenstrom's macroglobulinemia (WM) is a rare lymphoproliferative disorder (LPD) characterized by lymphoplasmacytic infiltration of the bone marrow (BM) and/or occasionally other tissues and by the presence of a serum monoclonal IgM. The disease belongs to the lymphoplasmacytic lymphoma (LPL) subtype. Whether WM is indeed a separate entity or is merely an IgM-secreting subtype of low-grade B-cell lymphoma is still controversial. In our series of 67 patients, WM has a long median overall survival of 110 months, and the male/female ratio is 1.2/1. Clinical features include a wide spectrum of manifestations, many of which may be common to other LPDs. Differential diagnosis is based on: (1) clinical and laboratory features (anemia, organomegaly, lymphadenopathy, IgM paraproteinemia), (2) cell morphology (lymphocytes, lymphoplasmacytes, few plasma cells), (3) histopathology of bone marrow or lymph node, (4) immunophenotype (CD5 expression and the intensity of CD5, CD20, and CD79b antigens may help in discrimination from other LPDs and atypical CLL), and (5) characteristic genetic features (present in other LPDs). Based on the former, diagnosis is usually easy. It may be harder in LPL cases not secreting IgM. We consider that WM should be, for the time being, handled as a separate entity. Further studies are necessary.     

Mast cells in Waldenstrom's macroglobulinemia support lymphoplasmacytic cell growth through CD154/CD40 signaling.

Bone marrow (BM) mast cells (MC) are commonly found in association with lymphoplasmacytic cells (LPC) in patients with Waldenström's macroglobulinemia (WM). We therefore sought to clarify the role of MC in WM. Co-culture of sublethally irradiated HMC-1 MC, KU812 basophilic cells, or autologous BM MC along with BM LPC from WM patients resulted in MC dose-dependent tumor colony formation and/or proliferation as assessed by ³H-thymidine uptake studies. Furthermore, by immunohistochemistry, multicolor flow cytometry and/or RT-PCR analysis, CD40 ligand (CD154), a potent inducer of B-cell expansion, was expressed on BM MC from 32 of 34 (94%), 11 of 13 (85%), and 7 of 9 (78%) patients, respectively. In contrast, MC from five healthy donors did not express CD154. By multicolor flow cytometry, CD154 was expressed on BM LPC from 35 of 38 (92%) patients and functionality was confirmed by CD154 and CD40 agonistic antibody stimulation, which induced proliferation, support survival and/or pERK phosphorylation of LPC. Moreover, MC induced expansion of LPC from 3 of 5 patients was blocked in a dose dependent manner by use of a CD154 blocking protein. These studies demonstrate that in WM, MC may support tumor cell expansion through constitutive CD154-CD40 signaling and therefore provide the framework for therapeutic targeting of MC and MC-WM cell interactions in WM.     

Developing diagnostic criteria in Waldenstrom's macroglobulinemia

Waldenstrom's macroglobulinemia (WM) is a poorly characterized B-cell lymphoproliferative disorder. There are a relatively limited number of detailed clinicopathological assessments, while the majority of clinical trials have been nonrandomized, single-institution phase II studies. Unfortunately progress in this disorder has been hindered by a lack of universally accepted diagnostic criteria. It is clear that criteria incorporating clinical, morphological, immunophenotypic, and, ultimately, genotypic parameters are needed for future clinical trails. Following a detailed clinicopathological assessment of 111 patients and a review of the published literature the following diagnostic criteria were proposed for WM: IgM monoclonal gammopathy of any concentration, bone marrow infiltration by small lymphocytes, plasmacytoid cells and plasma cells in a diffuse, interstitial or nodular pattern, and a surface Ig(+)CD19(+)CD20(+)CD5(-)CD10(-)CD23(-) immunophenotype.     

24例华氏巨球蛋白血症临床分析

目的 华氏巨球蛋白血症(Waldenstr(o)m's macroglobulinemia,WM)是一种特殊类型的非霍奇金淋巴瘤,其发病率极低,国内外相关数据较为缺乏.本研究旨在探讨WM的临床特点、预后因素及诊治方法. 方法 回顾性分析2011-01-01-2016-01-01郑州大学人民医院诊治的24例WM患者临床资料. 结果 24例WM患者,男16例,女8例,男女比例为2∶1,年龄42~79岁,中位年龄62.5岁;贫血(20例,83.3%)是最常见的临床表现,中位血红蛋白水平75(46~145) g/L;中位IgM水平32.9(6.4~79.3) g/L,其中κ型18例(75%),λ型6例(25%).16例患者行流式细胞术检测,13例(81.3%)表现为sIgM+CD5-CD10-CD19+CD20+CD22+CD23-.全组中位无进展生存时间(PFS)为7.5(1~51)个月.单因素分析结果显示,年龄、血红蛋白(Hb)、血小板(PLT)、β2微球蛋白(β2-MG)、IgM水平、白蛋白(ALB)、血清肌酐(SCr)、乳酸脱氢酶(LDH)、C反应蛋白(CRP)和合并重度免疫不全麻痹影响患者PFS,应用含有利妥昔单抗或硼替佐米的化疗方案组PFS相对较长.多因素分析结果显示,年龄(P=0.008)、IgM水平(P=0.028)和SCr(P=0.005)与预后相关. 结论 WM好发于老年男性,以IgM κ型多见,具有惰性B细胞淋巴瘤的特点,年龄、IgM水平和SCr是影响WM预后的独立危险因素,利妥昔单抗或硼替佐米的应用有望延长PFS.     

CD56 expression predicts occurrence of CNS disease in acute lymphoblastic leukemia

We examined the pre-treatment bone marrow samples from 200 consecutive adult patients with acute lymphoblastic leukemia (ALL) treated on various protocols at the University of Texas, M.D. Anderson Cancer Center between 1986 and 1998. Standard MFC techniques were used to determine CD56 expression on the leukemia blasts cells. The expression of CD56 was correlated with clinical characteristics at diagnosis, response to therapy, survival and disease-free survival.Blast expression of CD56 (> or = 20% of leukemic blasts) was seen in 16 (8%) of patients, with a median expression of 67% (range 20-99%). CD56 expression was associated with a higher incidence of central nervous system (CNS) disease at diagnosis (19% versus 4%; P=0.016). Incidence of CNS disease at any time was higher in patients with CD56+ disease (31% versus 14%; P=0.057). Among the 109 patients uniformly treated with the hyperCVAD regimen, CD56 expression was associated with a statistically significant higher incidence of CNS disease (33% versus 9%; P=0.026). CD56 expression in ALL is uncommon but may predict a higher risk for CNS disease. If these results are confirmed, CD56 expression could be used in combination with other high-risk features (e.g. lactate dehydrogenase (LDH), S-phase fraction, mature B-cell phenotype) to design a risk-oriented approach to CNS prophylaxis.     

Immunohistochemical expression of CD23 and CD40 may identify prognostically favorable subgroups of diffuse large B-cell lymphoma: a Nordic Lymphoma Group Study.

PURPOSE: In search for subgroups of diffuse large B-cell lymphoma (DLBCL) with different histogenetic origin and prognosis, as has been described by gene expression profiling, we examined tumor specimens from 125 patients with DLBCL, uniformly treated by either cyclophosphamideAdriamycin-vincristine-prednisone or methotrexate, doxorubicin, cyclophosphamide, vincristine, prednisone, and bleomycin in a multicenter trial set by the Nordic Lymphoma Group 1989-1994. EXPERIMENTAL DESIGN: Bcl-6, CD10, and CD40 were chosen as markers for a germinal center phenotype, CD23 as a marker of pre/early germinal center origin, and CD138 as a marker for postgerminal center origin. In addition, expression of the apoptotic regulators bcl-2 and bax was analyzed. Immunohistochemical analysis was performed using the EnVision method. RESULTS: CD10 was positive in 51%, bcl-6 in 97%, and CD138 only in 2% of the cases. No prognostic conclusions could be drawn from analysis of these factors. CD40 was positive in 76% of the cases. This group was associated with superior time to treatment failure (P = 0.027) and overall survival (OS; P = 0.0068). By Cox regression analysis, positivity for CD40 was shown to be a prognostic factor for OS, independent of International Prognostic Index. CD23 was positive in 16% of the cases (all CD5 negative and all CD40 positive). This group showed a strong tendency for better OS (P = 0.033). CD40 expression correlated with bax but not with bcl-2 expression. CONCLUSIONS: CD23 and CD40 expression seems to be prognostically favorable in DLBCL. This may be secondary to a germinal center origin or attributable to increased apoptosis via induction of bax and/or enhanced T-cell interaction, resulting in improved autologous tumor response. Confirmatory studies are necessary.     

Quantitative analysis of bcl-2 expression in normal and leukemic human B-cell differentiation.

Lack of apoptosis has been linked to prolonged survival of malignant B cells expressing bcl-2. The aim of the present study was to analyze the amount of bcl-2 protein expressed along normal human B-cell maturation and to establish the frequency of aberrant bcl-2 expression in B-cell malignancies. In normal bone marrow (n=11), bcl-2 expression obtained by quantitative multiparametric flow cytometry was highly variable: very low in both CD34(+) and CD34(-) B-cell precursors, high in mature B-lymphocytes and very high in plasma cells. Bcl-2 expression of mature B-lymphocytes from peripheral blood (n=10), spleen (n=8) and lymph node (n=5) was significantly higher (P<0.02) in CD23(-) as compared to CD23(+) B cells, independent of the type of tissue analyzed. Upon comparison with normal human B-cell maturation, bcl-2 expression in neoplastic B cells from 144 patients was found to be aberrant in 66% of the cases, usually corresponding to bcl-2 overexpression (63%). Follicular lymphoma (FL) carrying t(14;18) and MALT lymphoma were the only diagnostic groups constantly showing overexpression of bcl-2. Bcl-2 overexpression was also frequently found in precursor B-acute lymphoblastic leukemia (84%), typical (77%) and atypical (75%) B-cell chronic lymphocytic leukemia, prolymphocytic leukemia (two of three cases), mantle cell lymphoma (55%), but not in t(14;18)(-) FL, splenic marginal zone lymphoma, Burkitt lymphoma and multiple myeloma.     

Clinicopathologic features of Waldenstrom's macroglobulinemia and marginal zone lymphoma: are they distinct or the same entity?

Waldenstrom's macroglobulinemia (WM) is considered in the World Health Organization classification as a clinical syndrome associated with monoclonal immunoglobulin (Ig) M secretion, mainly observed in patients with lymphoplasmacytic lymphoma (LPL) and occasionally with other small B-cell lymphomas. Some authors consider it a rare distinct lymphoproliferative disorder with primary bone marrow infiltration and IgM monoclonal gammopathy. As LPL shares important morphologic and immunophenotypic overlaps with marginal zone B-cell lymphomas (MZLs) in cases showing plasmacytic maturation, it remains unclear if they constitute unique or distinct entities. Both diseases are composed of lymphocytes, lymphoplasmacytoid cells, and tumoral plasma cells with a surface (s) IgM-positive sIgD+/ cytoplasmic IgMpositive CD19+ CD20+ CD27+/ CD5 CD10 CD23 phenotype, without a specific marker. Extranodal mucosa-associated lymphoid tissue (MALT) lymphoma, nodal MZL (NMZL), and splenic MZL (SMZL) are distinct entities displaying common morphologic, immunophenotypic, and genetic characteristics. MALT lymphoma is clearly distinct from LPL, although bone marrow infiltration and IgM paraprotein are not rare. Splenic MZL and NMZL are incompletely characterized, but a plasmacytoid/plasmacytic differentiation, autoimmune manifestations, and monoclonal component are frequent in both diseases. Bone marrow involvement is constant in SMZL and present in 60% of NMZLs. Molecular IgVH gene analysis has confirmed this heterogeneity, particularly within SMZL, with mutated and unmutated cases. Further studies are needed to clarify the pathogenesis of these MZLs and their relationship with LPL.     

PD-L1、PD-L2、CD30、CD23和BCL-6在原发纵隔大B细胞淋巴瘤诊断和预后评估中的应用价值

目的 探讨治疗相关标志物PD-L1、PD-L2、CD30、CD23、BCL-2、BCL-6、MUM1和GATA3在原发纵隔大B细胞淋巴瘤（PMBL）诊断和预后评估中的应用价值。方法 收集PMBL的34例患者进行回顾性研究,31例非纵隔原发的非特指型弥漫性大B细胞淋巴瘤（DLBCL-NOS）作为对照组,免疫组织化学染色方法检测8种蛋白的表达情况。结果 PD-L1、PD-L2和CD30在PMBL组阳性肿瘤细胞百分比的中位数分别为70%（30%, 90%）、25%（0, 70%）和17.5%（0, 60%）,显著高于DLBCL-NOS组,差异有统计学意义（P<0.05）;CD30和CD23在PMBL组的阳性率分别为61.76%（21/34）和76.47%（26/34）,与DLBCL-NOS组之间差异有统计学意义（P=0.000）。伴有CD30或BCL-6表达的PMBL患者生存曲线尽管P>0.05,仍显示出预后差的趋势。结论 PMBL中PD-L1、PD-L2和CD30的表达水平较高,有助于精准识别更多可能对免疫或靶向治疗有反应的患者。免疫组织化学标记PD-L1、PD-L2、CD30和CD23有助于PMBL与DLBCL-NOS鉴别诊断。CD30和BCL-6作为PMBL的候选预后指标应该在更大量的样本中进一步研究。     

Prognostic value of bcl-6, CD10 and CD38 immunoreactivity in stage I-II gastric lymphomas: identification of a subset of CD10+ large B-cell lymphomas with a favorable outcome

bcl-6, CD10 and CD38 are useful markers for identifying 2 molecularly and prognostically distinct profiles of diffuse large B-cell lymphomas (LCLs), defined as germinal-center B-like and activated B-like. We investigated the prognostic role of bcl-6, CD10 and CD38 immunoreactivity in 102 gastrectomized patients with primary gastric lymphomas (PGLs). There were 41 low-grade marginal zone lymphomas of MALT-type (LGML) and 61 diffuse large B-cell lymphomas with (DLCLMLs; n = 31) or without (DLCLs; n = 30) an LGML component. bcl-6, CD10 and CD38 were significantly more commonly expressed in DLCL or DLCML as compared with LGML (50% vs. 48% vs. 17%, p = 0.0002 for bcl-6; 27% vs. 26% vs. 0%, p = 0.0004 for CD10; 45% vs. 48% vs. 13%, p = 0.0005 for CD38, respectively). CD10 immunoreactivity was independently associated with a better survival in diffuse LCL patients (5-year overall survival: 88% +/- 8% vs. 66% +/- 7%; p = 0.04); bcl-6 or CD38 immunoreactivities did not disclose any prognostic implication. Age, presence of LGML component, lactic dehydrogenase serum levels and use of chemotherapy were additional independent prognostic factors. We conclude that CD10 immunoreactivity assessment could be a clear, easy-to-interpret and reliable prognostic factor in PGL. Accordingly, patients with CD10(+) gastric large B-cell lymphomas may be at reduced risk and eligible for clinical trials evaluating more conservative therapeutic options.     

Extramedullary infiltrates of AML are associated with CD56 expression, 11q23 abnormalities and inferior clinical outcome

We evaluated the frequency and prognostic significance of extramedullary infiltrates (EMI) at presentation of acute myeloid leukemia (AML) in adult patients. Of 331 cases with de novo AML, 101(30.5%) had extramedullary infiltrates at diagnosis. The extramedullary manifestations included: lymphadenopathy, splenomegaly, hepatomegaly, gingival hypertrophy, skin infiltrates and involvement of central nervous system (CNS). Patients with EMI had a high initial WBC count and a high proportion of M4/M5 morphological variants. The complete remission rate (CR) with induction chemotherapy was lower in patients with EMI (P=0.0077) and their overall survival was also inferior (P=0.0017). Flow cytometric evaluation of the surface antigens expressed by the leukemic blasts for CD34, TdT, HLADR, CD7, CD19 and CD56 found that only CD56 expression was associated with EMI. The association of CD56 expression with lymphadenopathy was statistically significant (P=0.035). Abnormal karyotypes were found in 50.6% of patients with EMI and 49.7% of patients without EMI. Only 11q23 abnormalities were associated with specific sites of EMI; lymphadenopathy (P=0.0111) and gingival hypertrophy (P=0.0016). Our study of adult AML patients demonstrates that EMI at diagnosis is associated with CD56 expression by leukemic blasts, 11q23 karyotypic abnormalities, low complete remission rate and poor overall survival.     

Peripheral blood CD38 expression predicts survival in B-cell chronic lymphocytic leukemia

CD38 expression was investigated in 161 untreated patients with B-cell chronic lymphocytic leukemia (B-CLL). A score system, devised ad hoc by integrating the percentage and the mean fluorescence intensity (MFI) values of CD38(+) cells, indicated that B-CLL patients with a CD38 score < or =3 are characterized by a significantly longer survival compared to those with a CD38 score >3 (P=0.0026). Thirty-seven percent of patients with a CD38 score < or =3 and 58% of those with a score >3 were dead at 10 years. Multivariate analysis indicates that only the CD38 score successfully predicts survival (P=0.0028), with an estimated 3.8-fold greater risk of death for those cases with CD38 score >3.     

Response to Brentuximab Vedotin by CD30 Expression in Non-Hodgkin Lymphoma

BackgroundThe safety and efficacy of brentuximab vedotin (BV), an antibody-drug conjugate directed to the CD30 antigen, has been assessed in several trials in patients with peripheral T-cell lymphoma (PTCL), cutaneous T-cell lymphoma (CTCL), or B-cell non-Hodgkin lymphoma (NHL). The objective of this research was to examine the relationship between CD30 expression level and clinical response to BV.Patients and MethodsWe analyzed response in patients treated with BV monotherapy in 5 prospective clinical studies in relapsed or refractory PTCL, CTCL, or B-cell NHL. CD30 expression was assessed by immunohistochemistry (IHC) using the Ber H2 antibody for 275 patients.ResultsAcross all 5 studies, 140 (50.9%) patients had tumors with CD30 expression <10%, including 60 (21.8%) with undetectable CD30 by IHC. No significant differences were observed for any study in overall response rates between patients with CD30 expression ≥10% or <10%. Median duration of response was also similar in the CD30 ≥10% and <10% groups for all studies.ConclusionsIn this analysis of studies across a range of CD30-expressing lymphomas, CD30 expression alone, as measured by standard IHC, does not predict clinical benefit from BV, making the determination of a threshold level of expression uncertain.     

Clinicopathological Correlates of IgM Paraproteinemias

IgM paraproteinemia is considered to be the major defining feature of Waldenström's macroglobulinemia (WM), but it may also occur in other B-cell lymphoproliferative disorders. In this study we have reviewed the final pathological diagnosis of 106 patients with IgM paraproteinemia investigated in our laboratories between April 1993 and May 1999. In 22 of the 106 patients (20.8%), there was no clinical or laboratory evidence of an underlying lymphoproliferative disorder, and a diagnosis of monoclonal gammopathy of undetermined significance (MGUS) was therefore made. In 60 cases (56.6%), a diagnosis of WM was made, while in the remaining 24 patients, the final diagnosis was chronic lymphocytic leukemia (n = 10), diffuse large B-cell lymphoma (n = 5), extranodal marginal-zone lymphoma (n = 3), follicular lymphoma (n = 3), and mantle-cell lymphoma (n = 3). The median paraprotein concentration in patients with WM, MGUS, and “other” lymphoproliferative disorders was 13 g/L (range, 2–54), 6 g/L (range, 3–30), and 4.5 g/L (range, 3–61), respectively. It is clear that IgM paraproteins are demonstrable in all subtypes of peripheral B-cell disorders and, although paraprotein concentrations are generally higher in WM, there is considerable overlap. Immunophenotypic criteria are therefore essential for the accurate diagnosis of WM.