原发性脑淋巴瘤的MRI表现特点与诊断

目的：分析颅内原发性淋巴瘤的MRI表现特点，为临床诊断与治疗提供资料。方法：回顾分析28例经病理证实颅内原发性淋巴瘤的MRI资料，所有病例均行平扫及增强扫描。结果：病灶单发6例，多发22例，分布于幕上14例，幕下4例，幕上幕下同时存在10例，大多位于深部脑白质，病灶多呈圆形或不规则形，T1WI呈低信号，T2WI呈等或高信号，瘤周水肿较轻，增强扫描病灶均呈团块状显著强化。结论：颅内淋巴瘤的MRI表现缺乏特异性，需手术或活检才可作出定性诊断。     

Fine-needle aspiration biopsy in diagnosis of follicular lymphoma: cytomorphologic and immunohistochemical analysis

Follicular lymphoma is a relatively uncommon type of non-Hodgkin's lymphoma (NHL) thought to derive from follicular center cells. There are limitations to fine-needle aspiration in the diagnosis of follicular NHL, and very few studies are available on it. We describe here the cytomorphologic features of eight biopsy-proven cases of follicular NHLs and five biopsy-proven cases of intermediate-grade NHLs. Five cases of reactive lymphoid hyperplasia (RLH) diagnosed on cytology were also studied cytomorphologically. Image morphometry was done in follicular and intermediate-grade NHLs, immunocytochemistry was done in follicular and intermediate-grade NHLs, and immunocytochemistry for bcl-2 expression was studied in five cases of follicular NHLs. The aspirate smears of follicular NHL showed the presence of higher grades, many to abundant (++ to +++) monomorphic lymphoid aggregates, with an increased number of mast cells. Lymphohistiocytic tangles and tingeable body macrophages were not observed in any of the cases. Cytomorphologically, all the cases of intermediate-grade NHL showed a predominantly monomorphic population of lymphoid cells with absent or few grades (+) of lymphoid aggregates. Image morphometric data analysis of each cell parameter for follicular and intermediate-grade NHLs were found to be statistically insignificant (P > 0.05) and hence of little help in diagnosis of follicular vs. low-grade NHLs. Immunocytochemistry for bcl-2 expression in follicular NHL showed variable results, ranging from 0-90% (expressed as bcl-2 index). Certain characteristic cytomorphological features such as the presence of monomorphic lymphoid cell aggregates and an increased number of mast cells are soft indicators for the diagnosis of follicular NHL on aspiration smears. Immunocytochemistry for bcl-2 expression may be of help in cases with clinical and cytological suspicion of lymphoma. Image morphometry has a small role in this regard.     

淋巴结血管内T细胞淋巴瘤1例报道及文献复习

目的　探讨血管内淋巴瘤 (IVL)的临床病理特征。方法　对 1例腹股沟淋巴结IVL临床、病理组织学及免疫表型进行观察分析并复习文献。结果　男性 31岁 ,不明原因高热伴消瘦 5 0天 ,右腹股沟直径 1cm淋巴结 1枚 ,B超示肝脏轻度增大 ,血LDH明显升高伴ESR及转氨酶轻度升高 ,外周血WBC 3 3× 10 7/L ,骨髓像、多种病原及各肿瘤相关抗原检测均无异常。病理活检 :腹股沟淋巴结大部分破坏 ,代之以大量扩张的中小血管 ,腔内充满大量异型淋巴样细胞 ,局部伴管壁、管周浸润并累及结外脂肪组织。瘤细胞免疫表型CD4 5、CD4 5RO、CD3阳性 ,CK、CD6 8、CD79α、CD2 0均阴性 ,血管壁及内皮细胞CD31、CD34阳性。行CHOP化疗后症状缓解 ,现仍在随访中。结论　IVL是一罕见的非霍奇金淋巴瘤 ,好发于中枢神经系统及皮肤 ,其他部位少见 ,绝大数为B细胞型 ,T型罕见 ,以浅表淋巴结活检确诊者尚无报道。临床表现有一定提示性 ,确诊靠组织病理学检查 ,部分病例对化疗敏感 ,但多数病例预后差     

荷EL4肿瘤小鼠模型的建立及美法仑抑瘤作用免疫机制的探讨

目的:建立荷小鼠淋巴瘤EL4的野生型C57BL/6小鼠及其裸鼠模型,探讨美法仑(melphalan)抑瘤作用的免疫机制。方法:给正常野生型C57BL/6小鼠皮下接种小鼠淋巴瘤EL4细胞,建立荷EL4肿瘤的小鼠模型。于野生型C57BL/6小鼠皮下接种瘤细胞后12d,经腹腔给荷瘤小鼠单次注射不同剂量的美法仑,找出美法仑可发挥最大的抑瘤作用,并能致使肿瘤消退、不再复发的最小使用剂量。然后再给野生型C57BL/6小鼠及其裸鼠(遗传背景相同)皮下同时接种小鼠淋巴瘤EL4细胞建立两种荷瘤小鼠模型。同样于接种瘤细胞后12d,经腹腔给两种荷瘤小鼠模型均注射可使野生型C57BL/6小鼠肿瘤消退、不再复发的最低剂量的美法仑,以正常野生型C57BL/6小鼠为对照,观察在T淋巴细胞缺陷的裸鼠体内美法仑的抑瘤作用。结果:注射7.5mg/kg美法仑治疗后,免疫功能正常的野生型C57BL/6荷瘤小鼠的肿瘤消退;而荷瘤C57BL/6裸鼠的肿瘤仍继续生长。结论:单一剂量的美法仑对荷淋巴瘤EL4小鼠具有明显的治疗作用,其作用的发挥需要T淋巴细胞的参与,可能与T细胞的杀伤作用有关。     

Real-time PCR method for the quantitative analysis of human T-cell receptor gamma and beta gene rearrangements

Analyzing the status of T-cell receptor (TCR) gene rearrangements has been an essential part of deciphering the stages of thymocyte development, understanding the β vs. γδ lineage decision, and characterizing T-cell leukemias. Methods such as PCR and quantitative Southern blotting provide useful information, but also have significant shortcomings such as lack of quantitation in the case of PCR and technical challenges in the case of Southern blotting. Here we describe a real-time PCR method that overcomes many of these shortcomings. This new method shows comparable results for the fraction of unrearranged TCRγ and TCRβ genes in human thymocytes and peripheral blood T cells as Southern blotting, and has the advantages of being simple to perform, highly quantitative, and requiring nanogram quantities of DNA. We also describe a real-time PCR method to quantitate T-cell receptor excision circles formed during TCRβ rearrangements.     

Ultrastructural study of 4 cases of Ki-1 positive large anaplastic cell malignant lymphoma

Summary The ultrastructural morphology of 4 cases of large anaplastic cell malignant lymphoma (Ana ML) is reported. Three cases were primary Ana ML and one pleomorphic large T cell lymphoma with some Ki-1 positive cells. All were confirmed by immunohistochemistry on frozen and paraffin sections. The Ki-1 and EMA positive tumour cells had an abundant cytoplasm, with no differentiation and large pale nuclei with multiple compact or dispersed nucleoli. The morphology is that of an activated cell engaged in protein synthesis and/or in the mitotic cycle. These tumour cells resemble to the Hodgkin's and monolobated Reed-Sternberg cells described in Hodgkin's disease.     

The anaplastic variant of centrocytic lymphoma is marked by frequent rearrangements of the bcl-1 gene and high proliferation indices

Ten cases of classic centrocytic lymphoma as defined in the Kiel classification system were investigated for their immunophenotype, their proliferation activity and by means of molecular diagnostics. The findings were compared to those obtained from a group of nine cases of anaplastic centrocytic lymphoma. Both groups showed virtually identical immunohistochemical characteristics with positivity for CD5 and negativity for CD10 and CD23. In the group of anaplastic centrocytic lymphoma, there were considerably higher proliferation indices as documented by staining for the Ki-67 antigen, up to 80% of the tumour cells being positive. Moreover, the cases of anaplastic centrocytic lymphoma had bcl-1 gene rearrangements in eight out of nine cases compared with three out of 10 cases of classic centrocytic lymphoma. DNA analysis was not able to detect bcl-2 gene rearrangement in any case, pointing to a difference compared with lymphomas of germinal centre origin. The coincidence of anaplastic and sometimes blast-like morphology of the tumour cells, high proliferation index and a rearranged bcl-1 gene in nearly all cases of anaplastic centrocytic lymphoma support their classification as high-grade malignant variants of centrocytic lymphoma and suggest a possible role for the bcl-1 locus not only in the origin but also in the progression of centrocytic lymphomas.     

Differential diagnosis of HTLV-I-associated myelopathy and multiple sclerosis in Iranian patients

Summary Two Iranian patients with chronic progressive spastic paraparesis and urinary dysfunction were referred to our hospital with the presumptive diagnosis of multiple sclerosis (MS). Routine CSF analysis and magnetic resonance imaging of the two patients were only partially characteristic of MS. Testing for antibodies to human T-cell leukemia virus type I [HTLV-1] in serum using a radioimmune precipitation assay revealed antibodies to HTLV-I in both patients. The infection with HTLV-I was confirmed by polymerase chain reaction (PCR) and liquid hybridization analysis using primers to the tax/rex region and a corresponding probe, demonstrating proviral DNA in peripheral blood mononuclear cells of both patients. On the basis of these findings demonstrating the presence of proviral HTLV-1 DNA in the two Iranian patients, the initial diagnosis of MS was corrected to that of HTLV-I-associated myelopathy (HAM). In contrast, several patients with definite MS (nine from Germany, two from Iran) with a relapsing and remitting form of the disease were tested for HTLV-1 infection by enzyme-linked immunosorbent assay and PCR, which yielded negative results. However, the mother of one HAM patient was found to be infected with HTLV-I. To support an association between HTLV-I infection and CNS disease in the two HAM patients, we analyzed the production of specific IgG antibodies within the CNS based on a simple enzyme immunoassay for viral IgG antibodies in CSF and serum. In the two HAM patients there was significant intrathecal antibody production directed against HTLV-I, but this was not found in any of the samples from MS patients. These findings demonstrate an immune reaction to HTLV-I in the CNS of HAM patients, thus confirming the association of infection and CNS disease. The demonstration of intrathecal HTLV-I antibody production also proved useful for the differential diagnosis of MS or HAM, especially in patients from areas endemic for HTLV-I.Abbreviations DTPA diethylenetriaminepentaacetic acid - ELISA enzyme-linked immunosorbent assay - HAM HTLV-I-associated myelopathy - HTLV-I human T-cell leukemia virus type I - MRI magnetic resonance imaging - MS multiple sclerosis - PBMC peripheral blood mononuclear cells - PCR polymerase chain reaction - RIPA radioimmune precipitation assay - SDS sodium dodecyl sulfate - TSP tropical spastic paraparesis     

Telomerase activity and proliferation index in aggressive mature B-cell lymphoma: comparison to germinal center phenotypic markers

Cell proliferation may be evaluated by various methods, including Ki-67 immunohistochemistry and measures of telomerase activity. Both methods would theoretically show comparable increases in a given case. To evaluate the relationship between these 2 markers of proliferation in aggressive mature B-cell lymphomas, 48 cases were studied. The study group included 5 cases of mantle cell lymphoma (MCL); 6 cases of Burkitt's/Burkitt's-like lymphoma (BL); 9 cases of follicular lymphoma, grade 3 (FLC); and 28 cases of diffuse large B-cell lymphoma (DLC). Telomerase activity was measured as total product generated (TPG) units, and TPG results for the aforementioned cases were compared to the TPG results for 10 cases of reactive follicular hyperplasia. An overlap in TPG scores between reactive cases and lymphoma cases was found. Significant differences in both log TPG (P = 0.0443) and Ki-67 (P = 0.0006) were seen in the different lymphoma types. A positive correlation between Ki-67 percentage and TPG score was identified in FLC (r = 0.9281; P = 0.0003), but a poor correlation between these 2 indicators was seen in the other lymphoma types. Cluster analysis identified distinct patterns for MCL, FLC, and BL, but heterogeneous patterns for DLC. Because increases in both Ki-67 proliferation and telomerase activity are reported in normal germinal centers (GCs), these tests were also evaluated for usefulness as markers of a GC cell phenotype. Among the FLC and DLC cases, features of a GC phenotype significantly correlated with increased Ki-67 percentage (P = 0.0152), but not with increased log TPG. An elevated log TPG correlated with CD10 expression, and elevated Ki-67 percentage correlated with both CD10 and BCL-6 expression. TPG level and Ki-67 percentage did not correlate with the presence of t(14;18) or BCL-2 protein expression. Although the proliferation patterns were fairly distinctive for MCL, FLC, and BL, these studies show that markers of cell proliferation do not by themselves,identify distinct subtypes of large cell lymphomas. With the exception of FLC, the tumors exhibited poor correlation between telomerase activity and Ki-67 proliferation index. These tests did show some correlation with expression of GC cell phenotypic markers, however.