滤泡树状突细胞的超微结构及其与淋巴细胞的关系

本文利用HRP-抗HRP特异地标记了大鼠脾脏滤泡树状突细胞(FDC)。在透射电镜下观察了FDC的超微结构及其与淋巴细胞的关系。FDC外形不规则;核常染色质性,外形亦不规则,可呈分叶状;胞质呈一窄带环绕核周,发出树枝状突起;突起自起始部即变窄,分支、卷折,穿行在淋巴细胞之间。FDC周围常见淋巴母细胞,其突起常与淋巴母细胞指状小突起紧密相嵌;淋巴母细胞内线粒体相对集中在靠FDC突起的一侧。这提示FDC与淋巴母细胞之间存在某种功能联系,可能与FDC呈递抗原,刺激淋巴细胞使其发生母细胞化有关。     

HISTOLOGICAL AND FINE STRUCTURAL STUDIES ON PIGMENTED NEUROECTODERMAL TUMOR OF INFANCY

Pigmented neuroectodermal tumor of infancy originating from the anterior maxilla in a two-month-old male has been studied by light and electron microscopy. The tumor is characterized histologically by two types of neoplastic cells embedded in considerable amounts of fibrous stromal tissue. The first type of cell is cuboidal to columnar in shape with an epithelial appearance having abundant cytoplasm; either scanty or a heavy accumulation of melanin pigment is observed in the cytoplasm. These cells are aligned along the cleft-like space or arranged in small ductal structures. Electron microscopy shows the characteristic features of melanocytic cells having a varying degree of asynchronous maturation of melanosomes. The second type of cells is small and round in shape and has a hyperchromatic nucleus and scanty cytoplasm, resembling neuroblastic cells or lymphocytes. Electron microscopy reveals cytoplasmic processes resembling immature neurits which protrude into the intracellular space; a small number of secretory granules having a central core surrounded by a single limiting membrane are observed in the cytoplasm and cytoplasmic processes.     

滤泡树突状细胞肉瘤的临床病理观察

目的 探讨和分析滤泡树突状细胞肉瘤(FDCS)的临床病理特点及鉴别诊断.方法 应用组织学、免疫组织化学(EnVision法)标记及EBER原位杂交,对8例FDCS进行临床和组织病理学分析,并复习相关文献.结果 8例FDCS中男性5例,女性3例,平均年龄50岁.发生部位淋巴结4例,扁桃体、鼻咽部、肝、脾各1例.组织学:瘤组织呈席纹状、束状、弥漫性、旋涡状或结节状,肿瘤细胞呈合体样,境界不清,胞质较丰富,均质嗜伊红或细颗粒状,核呈卵圆形、短梭形或圆形,染色质稀疏或呈空泡状、点彩状,核仁明显,核分裂象多少不等,肿瘤细胞间见有散在淋巴细胞混杂.间质内可见假血管腔及血管周围淋巴鞘现象.其中肝脏1例以大量小淋巴细胞弥漫分布为背景,梭形或卵圆形的瘤细胞散在分布其中,瘤细胞核染色质细腻,部分区域细胞有轻度异形,核不规则、空泡状,有核仁.免疫组织化学瘤细胞均表达CD21、CD35、clusterin,部分表达CD68、上皮细胞膜抗原、S-100及内皮生长因子受体,Ki-67不同程度表达.EBER两例表达.结论 FDCS是一种非常少见的恶性肿瘤,易复发和转移,明确诊断需要结合病理形态学和免疫表型.     

小鼠乳腺腺癌细胞系MA782/5S-8102细胞的超微结构

对小鼠乳腺腺癌细胞系MA782/5 S-8102细胞的超微结构观察,可见细胞基质电子密度不同的亮细胞和暗细胞,细胞核呈明显畸形,核大,核仁数有所增加,核内异染色质浓聚,核膜肿胀,核质比例高。细胞质内核糖体、线粒体显著增加,粗面内质网明显扩张,高尔基体、溶酶体、脂质粒及微丝清楚可见,并观察到胞内A型病毒颗粒及从细胞表面微绒毛芽生的未成熟的B型样颗粒。细胞膜褶皱,细胞表面具有较丰富的微绒毛,在相邻细胞之间可观察到桥粒。结果表明MA782/5 S-8102细胞系细胞具有明显的恶性细胞特征。本文还对所出现的病毒进行了讨论。     

Adrenal extranodal NK/T‐cell lymphoma diagnosed by fine‐needle aspiration and cerebrospinal fluid cytology and immunophenotyping: A case report

The cytologic findings of an extranodal NK/T‐cell lymphoma (NKTCL) presenting as a large adrenal mass with leptomeningeal involvement diagnosed by CT‐guided fine‐needle aspiration and cerebrospinal fluid (CSF) cytology are described. The 65‐year‐old Caucasian patient presented with progressive headache and multiple cranial nerve neuropathies. Magnetic resonance imaging showed leptomeningeal enhancement surrounding the conus medullaris and cauda equine, and a subsequent PET/CT demonstrated a large right adrenal gland mass. Fine‐needle aspiration of the adrenal mass showed occasional large pleomorphic cells with prominent nucleoli, moderate amounts of cytoplasm, and rare large cells with sparse cytoplasmic granules admixed with numerous small lymphocytes. Initial flow cytometry from this sample showed no clonal B‐cell population. Immunoperoxidase stains performed on the cell block/core specimen showed that the large atypical cells were positive for CD2, CD30, CD43 and CD56, TIA‐1, granzyme, and perforin, but for none of the other T‐cell markers used (CD3, CD4, CD5, CD8, CD45RO), which stained the abundant background lymphocytes. A CSF specimen showed similar neoplastic cells and flow cytometry showed an NK‐cell population with aberrant immunophenotype. The cytologic findings of the neoplastic cells and the extensive panel of immunoperoxidase stains allowed the diagnosis of NKTCL, which was confirmed by the subsequent flow‐cytometric immunophenotyping performed on the CSF. This is, to the best of our knowledge, the first case of NKTCL diagnosed by FNA of the adrenal gland and by CSF cytology. Diagn. Cytopathol. 2009. © 2009 Wiley‐Liss, Inc.     

In situ observation of inflammatory cell-tumor cell interaction in human seminomas (germinomas): light, electron microscopic, and immunohistochemical study.

The precise functional significance of the inflammatory cells that infiltrate seminomas remains poorly understood. The present study analyzed 15 cases of testicular and extragonadal seminomas (germinomas) by light and electron microscopy, as well as by immunohistochemical methods, with emphasis on the inflammatory cell-tumor cell interaction. Ultrastructurally, in all 15 cases the lymphocytes (mainly consisting of small lymphocytes) were found to be in intimate contact with the intact tumor cells and with those that displayed damage of varying degree. In particular, relatively early damage, such as local loss of the membrane and/or cytoplasm, occurred at the contact regions. Often, the lymphocytes penetrated deeply into the cytoplasm, even into the nucleus of the tumor cell. In spite of the severe damage to the tumor cells, the lymphocytes were themselves intact. The stromal cells contacted by lymphocytes did not show damage. The tumor cells were in contact with epithelioid cells of granulomas in six cases and scattered macrophages in 11 cases showed damage similar to that seen in tumor cells in contact with lymphocytes. The great majority of the lymphocytes were UCHL1-positive cells. L26- or Leu-7-positive cells were rarely found. The epithelioid cells and scattered macrophages were positive for MAC387. The present morphologic study suggests that the infiltrating lymphocytes, epithelioid cells (probably derived from macrophages), and macrophages may be directly cytotoxic to the tumor cells in the microenvironments of testicular and extragonadal seminomas (germinomas).     

乳腺皮脂腺样癌临床病理诊断

目的探讨乳腺皮脂腺样癌的临床病理学特征及其诊断和鉴别诊断要点。方法对1例乳腺皮脂腺样癌进行光镜观察和免疫组化标记。结果癌组织由两型细胞构成：一型为未分化细胞,较基底细胞胞质丰富;另一型为较分化细胞,胞界清楚,胞体宽大,胞质丰富,有小空泡,两型细胞均可见1～3个小红核仁。癌细胞排列成不规则小叶,各小叶中两型细胞的数目和分布不一,部分似皮脂腺小叶结构。可见癌组织与残存小叶内导管上皮移行结构,部分区域伴鳞化。结论皮脂腺样癌为罕见的特殊类型乳腺癌,可能源自小叶内导管上皮皮脂腺化生。确诊须符合下列标准：①肿物位于乳腺实质内;②具备皮脂腺分化特点及恶性特征;③可见癌组织与乳腺导管上皮移行结构。     

巨噬细胞集落刺激因子受体在白血病细胞系中的表达和作用

目的 探讨巨细胞集落刺激因子受体（M－CSF－R）在人白血病细胞系中的表达及其作用。方法 采用ABC免疫酶标技术,间接免疫荧光染色,流式细胞计和蛋白免疫印迹研究了4株人白血病细胞系（J6-1,J6-2)来源于人粒－单型白血病,HL－60为来源于人急性粒细胞白血病的髓样细胞系,K562为来源于人慢性白血急变期胸水的髓样细胞系）和正常人外周单个核细胞及正常人脐带血单个核细胞M－CSF－R的分布,表达,分子大小及其作用。结果 正常人外周血单个核细胞未见M－CSF－R的表达,经PHA刺激后有低水平的表达;4株人白血病细胞系都高表达M－CSF－R,分布于细胞膜,细胞质和细胞核,J6－1,J6－2,K562和HL－60细胞质和胞核M－CSF－R（M－CSF－cnR)平均阳性率分别为52．3％,44．3％,28．0％,65．3％;胞膜M－CSF－R（M－CSF－mR)阳性率分别为78．9％,72．0％,54．9％,58．0％;高于正常人外周血单个核细胞的表达水平。HL－60细胞质和胞核中有一种相对分子质量为120000的M－CSF－R分子;4种白血病细胞表达的M－CSF－cnR的半衰期分别高于正常人脐带血单个核细胞经PHA诱导表达的M－CSF－cnR的半衰期;J6－1,J6－2,HL－60细胞表达的M－CSF－mR的半衰期亦明显延长。抗M－CSF－R单抗和人重组的M－CSF－R可溶性受体均能使4种白血病细胞的增殖阻断在G0／G1期,并能抑制其在软琼脂上形成集落的能力。结论 M－CSF－R在人白血病细胞系的表达呈异质性;胞内M－CSF－R的蓄积可能是白血病细胞M－CSF－R降解速率下降的结果,也可能是白血病细胞增殖的内源信号;M－CSF－R介导的信号是HL－60细胞增殖的重要和必要信号。     

A case report of angioimmunoblastic T cell lymphoma (AITL) with localization of neoplastic clear cells in the outer zone of germinal centers

Angioimmunoblastic T cell lymphoma (AITL) is characterized by the presence of atypical lymphocytes with clear cytoplasm and follicular dendritic cells, arborization of high endothelial blood vessels, and infiltration by inflammatory cells, such as epithelioid histiocytes, eosinophils, immunoblasts, and plasma cells. The neoplastic clear cells are localized around the high endothelial blood vessels or interfollicular areas. Recent reports have suggested that these neoplastic clear cells originate from helper T cells in germinal centers, based on their expression of CD10, PD-1, and CXCL13. We experienced a case of AITL which is histologically unique. A 61-year-old male presented to our hospital (Ogaki Municipal Hospital) with edema of his lower legs. Inguinal lymph node biopsy revealed that neoplastic clear T cells were mainly localized in the outer zone of germinal centers, specifically within the follicular dendritic cell (FDC) meshwork. Moreover, these cells were positive for CD3, CD4, CD10, CD43, CD45RO, PD-1, and weakly positive for CXCL-13. This is the first report showing that the neoplastic clear T cells were localized in the outer zone of germinal centers morphologically as well as immunohistochemically. In conclusion, this case report further supports the notion of germinal center helper T cell origin of neoplastic clear cells in AITL.     

Emperipolesis-like invasion of neoplastic lymphocytes into hepatocytes in feline T-cell lymphoma

Twelve cases of feline malignant lymphoma with emperipolesis-like invasion of neoplastic lymphocytes were examined microscopically, immunohistochemically and ultrastructurally. Intracytoplasmic invasion of neoplastic cells varied in severity between the cases, between hepatic lobules and between areas within the lobules. The number of infiltrating neoplastic cells ranged from one to several per hepatocyte. Neoplastic cells exhibited widely varying morphology from case-to-case and cell-to-cell within each case, and contained eosinophilic cytoplasmic granules in four cases. Immunohistochemical examination revealed that neoplastic cells in 11 of the 12 cases expressed one or both T-cell markers (CD3 and TIA-1). Diagnosis of T-cell lymphoma was also confirmed by assessment of clonality by polymerase chain reaction. Ultrastructural analysis revealed that the neoplastic lymphocytes were contained within an invagination of the cell membrane of the hepatocyte, rather than directly infiltrating into the cytoplasm of the cell. There was no evidence that the invasive neoplastic lymphocytes had a cytotoxic effect.     

基于影像组学的脑脊液细胞分类方法

目的：基于影像组学构建出更为高效、准确的脑脊液细胞判别模型。方法：回顾性收集3331张脑脊液细胞显微图像,其中吞噬细胞167张、单核细胞332张、淋巴细胞1081张、中性粒细胞1751张。首先在显微图像上分割出细胞核、细胞核凸包区域和细胞核凸包区域的部分细胞质,然后设计3种细胞核形状特征,即圆度、凸度、坚固性。针对细胞核、凸包区域和凸包区域的部分细胞质设计48种颜色特征。基于细胞核凸包区域提取4 676种纹理特征。结果：共提取了4 727个影像组学特征,在经过ANOVA和LASSO特征选择之后,保留了519个特征,且形状特征和颜色特征都得到了较高比例的保留（100.0%, 66.7%）。特征选择之后,利用SMOTE数据增强和SVM分类器在测试集上进行预测,各项评价指标Accuracy、Sensitivity、Specificity、Precision、F1＿score、AUC高达0.953、0.948、0.990、0.961、0.955、0.996。结论：本文提出的新的细胞显微图像特征提取方案和分类模型对细胞分类问题非常有效,且避免了细胞质分割的难题,无需分割细胞,只需分割细胞核和细胞...     

实验性变应性脑脊髓炎髓鞘脱失机制的研究

目的：探讨自身免疫性脱髓鞘疾病的中枢神经系统(CNS)髓鞘脱失发生机制。方法：采用同源脑白质匀浆建立猴实验性变应性脑髓炎(EAE)模型，并用流式细胞仪检测血和脑脊液淋巴细胞亚群的变化，用免疫组化技术和电镜观察脑组织病理变化。结果：急性EAE猴脑脊液CD4^ T淋巴细胞明显升高，CD8^ T淋巴细胞和B淋巴细胞轻度升高；颞叶深部白质有大量CD4^ T淋巴细胞和少量CD8^ T淋巴细胞浸润，而对照组均未见变化；髓鞘内板层松解和轴突髓鞘分离，而髓鞘外板层正常，轴突也保存完好，少突胶质细胞(ODC)的部分胞浆明显水肿，线粒体肿胀，嵴模糊或断裂，核部分溶解。结论：提示EAE脱髓鞘免疫因子最早攻击的靶是少突胶质细胞，而不是髓鞘本身。     

人胃癌肿瘤浸润树突状细胞的形态学观察

目的　探讨人胃癌肿瘤浸润树突状细胞 (TIDC)的形态学特征。方法　应用免疫组织化学、光镜和电镜的方法观察人胃癌TIDC的分布和形态学变化。结果　TIDC主要分布癌周区 ,病变早期TIDC比病变晚期数量 (P <0 0 1)。电镜下 ,TIDC体积较大 ,形态不规则 ,表面有许多树突状突起 ,细胞核不规则 ,可见核仁 ,胞质内有丰富的线粒体、核糖体、高尔基复合体和内质网。TIDC与肿瘤浸润淋巴细胞 (TIL)和肿瘤接触方式和形式上呈多样性 ,一对一 ,一对多 ,或形成簇的接触方式 ,有紧密膜接触、指状膜接触和球状膜接触形式。结论　本实验提示TIDC数量多少与肿瘤的进展有关 ,TIDC与肿瘤浸润淋巴细胞和肿瘤细胞之间关系密切。     

Latent herpesvirus hominis 1 in the central nervous system of psychotic patients.

Cerebrospinal fluids (CSF) from 35 patients with senile or presenile dementia and from 13 patients with schizophrenia and related syndromes were examined in cell cultures with the aim to isolate Herpesvirus hominis 1 (HVH 1) or other viruses. Serum and CSF antibodies to HVH 1 and/or interferon in the patients indicated a recent HVH 1 antigenic or viral activity. In the CSF of two senile demented patients and of one patient with schizoaffective psychosis, agents of low virulence, causing a cytopathic effect in 3 or 4, but not more, subsequent passages were detected and identified as HVH 1 by immunofluorescence. A focus of cells containing HVH 1 antigen at the cell membrane and in cytoplasm was visualized by immunofluorescence in an explant from nucleus amygdalae from 1 of 6 patients with schizophrenia and related syndromes examined. In the original biopsy materials, various virus-like structures were found in nuclei and cytoplasm of astrocytes and neurocytes and in axons in the neuropil.     

小肠系膜淋巴结外滤泡树突状细胞肉瘤

目的 探讨淋巴结外滤泡树突状细胞肉瘤的临床病理学特征和免疫学表型。方法 对1例发生于小肠系膜的淋巴结外滤泡树突状细胞肉瘤进行光镜观察和免疫组化标记。结果 镜下显示特征性的双相性细胞结构，由旋涡状排列的胖梭形、卵圆形或多边性瘤细胞和大量混杂的小淋巴细胞组成。瘤细胞胞界不清，呈合体状。胞质淡嗜伊红色，核圆形或卯圆形，有清晰的核膜，染色质呈空泡状或点彩状，可见小核仁，灶性区域可见分叶状或多核性瘤细胞。瘤细胞核显示轻到中度的异型性，可见核分裂象。肿瘤内可见凝固性坏死灶。除与瘤细胞相混杂外，部分区域内可见淋巴细胞聚集于血管周围，形成袖套结构。免疫表型：瘤细胞表达CD21，弱阳性表达EMA，而CD35、S100蛋白、desmin和AE1／AE3等标记均为阴性，大多数小淋巴细胞表达CD45RO(UCHL-1)和CD3。结论 淋巴结外滤泡树突状细胞肉瘤是一种罕见的免疫辅助细胞中度恶性肿瘤，应予以完整切除，必要时辅以化疗和(或)放疗。     

A morphometric study on the ultrastructure of well-differentiated tumours and inflammatory mucosa of the human urinary bladder

Summary Transmission (TEM) and scanning electron microscopic (SEM) observations were performed on well-differentiated tumours and chronic cystitis in the human urinary bladder. SEM showed that the pleomorphic microvilli were present not only on the luminal surface of the tumour but also on the surface of inflammatory mucosa. The ultrastructure of six tumours and 5 cases of chronic cystitis was evaluated morphometrically. Bladder tumour and inflammatory mucosa were divided into several layers, namely outermost cells (S), subsurface cells just beneath these (S1), subsurface cells of 2 or 3 layers below (S23), intermediate cells of 2 or 3 layers above the basal cells (123), intermediate cells just above the basal cells (I1) and basal cells (Ba). Areas of nucleus, cytoplasm and cytoplasmic organelles, numbers of nucleoli, nuclear bodies, mitochondria and lysosomes together with irregularity of the cell and nucleus were estimated according to the methods of Weibel. A multi-variate analysis of variance on these variables showed that the above subdivision of layers was necessary for the comparison of tumour and inflammation. Discriminant analysis showed various differences between tumour and inflammatory mucosa. The results indicated that the Ba layer is the most effective site for differentiating the tumour from inflammation. Ba cells with large and irregular cytoplasm with an enlarged Golgi area, accompanied by many vacuolar structures, may be indicative of tumour rather than inflammation.     

Histiocytic sarcoma with interdigitating dendritic cell differentiation: A case report with fine needle aspiration cytology and review of literature

A hybrid histiocytic sarcoma‐interdigitating dendritic cell sarcoma was found in a small perinephric lymph node of an asymptomatic 80‐year‐old man, who presented a year ago with two small foci of lung metastasis found during routine chest X‐ray. Fine needle aspiration cytology demonstrated interconnecting long and thin cell processes radiating from dendrite‐like neoplastic cells with oval, enlongated, reniform, and irregular nuclei with vesicular chromatin and distinct nucleoli. Histology showed spindled epitheliod and histiocytic cells with abundant, slightly eosinophilic cytoplasm with indistinct cell borders and forming fascicles in a vague storiform pattern with interspersed T‐lymphocytes. Immunohistochemically, the neoplastic cells were strongly positive for histiocytic markers: CD163, CD68, lysozyme, and PU.1, as well as strongly positive for dendritic cell markers: S100 and fascin, but were negative for CD1a (Langerhans cell marker), CD21/CD35 (follicular dendritic cell markers), B‐cell, and T cell markers. This case is compared to the four hybrid histiocytic‐dendritic sarcomas reported since 1983. Diagn. Cytopathol. 2010. © 2009 Wiley‐Liss, Inc.     

Non-Hodgkin's lymphoma classification: ultrastructural morphometric studies for the quantification of nuclear compartments in situ

The condensed chromatin distribution in the nuclei of lymphocytes in non-Hodgkin's lymphoma (NHL) is a key element, along with nuclear size and shape, in the classification of this disease for therapeutic and prognostic purposes. This report describes the ultrastructural comparative quantification of the condensed chromatin and the interchromatinic (nuclear matrix or euchromatin) region in the nuclei of mitogen-stimulated human peripheral T lymphocytes and mouse spleen B lymphocytes, human germinal center lymphocytes, and lymphocytes in ten cases of NHL of a variety of subtypes. The sequential morphologic nuclear changes induced in lymphocytes by mitogens are reflected in human germinal center lymphocyte populations. The common features include the changes in the distribution and volume of condensed chromatin aggregates, as well as the fact that the major increments in nuclear volume during lymphocyte transformation result from increases in the volume of the interchromatinic region. In all subtypes of NHL analyzed morphometrically, subpopulations of lymphocytes were identified in which mean nuclear, condensed chromatin, and interchromatinic volumes were more or less equivalent to those of normal lymphocyte subsets in germinal centers in reactive hyperplasia. However, in NHL the abnormal cytologic characteristics of the nucleus result, at least in part, from a complex interplay of condensed chromatin distribution and amount, and the size of the interchromatinic region. Further complexity is introduced by the fact that in NHL these two nuclear compartments can independently be normal, increased, or reduced in size. Morphometric quantification of lymphocytes in NHL indicates that the interchromatinic (matrix) region of the nucleus is the key element in establishing the nuclear volume of neoplastic lymphocytes. The structural and functional, ribonucleoprotein interchromatinic region of the nucleus was visualized in normal and neoplastic lymphocytes by regressive uranyl-EDTA staining. Quantitative morphometric analysis indicates that the cytologic appearance of neoplastic lymphocytes, even within subtypes of NHL, is heterogeneous and that condensed chromatin quantity and distribution may be more critical than nuclear size in distinguishing between certain subtypes of NHL. Improvements in the classification of NHL will occur only with understanding of the alterations in the biologic mechanisms controlling gross nuclear organization and the morphologic events of the various differentiation pathways available to antigen-stimulated lymphocytes.     

Distinguishing adenoid cystic carcinoma from cylindromatous adenomas in salivary fine-needle aspirates: the cytologic clues and their ultrastructural basis

The utilization of fine-needle aspiration (FNA) biopsy in salivary tumors is hindered by the reluctance of many cytopathologists to report adenoid cystic carcinoma (ACC) because its cylindromatous stroma is observed occasionally in pleomorphic adenoma (PA) and basal cell adenoma (BA), and a diagnosis of ACC results in radical surgery. The aim of this study is to identify dependable features to distinguish the look-alike entities and illustrate their ultrastructural base.We compared 20 cases of ACC to 15 cases of cylindromatous PA and 9 cases of BA. All were direct smears stained with Diff-Quik, hematoxylin and eosin, Papanicolaou, or Ultrafast Papanicolaou (UFP) stain. In addition to the presence of cylindromatous pattern, the amount of cytoplasm in the neoplastic cells and nuclear features were compared. Tissue was dissected from paraffin blocks and processed for electron microscopy in selected cases.The difference in nuclear features can be distinguished in UFP-stained smears and electron microscopy. The nuclei of ACCs were heterochromatic with coarse chromatin and irregular nucleoli, whereas the nuclei of PAs were euchromatic with fine chromatin and small compact nucleoli. The nuclei of BAs were hyperchromatic but finely textured. The cytoplasm of PAs was detectable with every stain at 40x objective, but the cytoplasm of BAs required UFP stain and 100x objective to be detected. The cytoplasm of majority of neoplastic cells of ACCs are invisible, because the thin rim of cytoplasm measured <1 microm ultrastructurally, well beyond the resolution of a light microscope. Rare cohesive fragment of epithelial cells in ACC have scanty blue cytoplasm in UFP stain and can be recognized as ductal cells.In conclusion, in our analysis of salivary tumors with a cylindromatous pattern, the seemingly naked nuclei of neoplastic cells with their coarse nuclear chromatin and irregular nucleoli, as revealed by the UFP stain, reliably distinguished ACC from cylindromatous adenomas.     

Guidelines for subtyping small B-cell lymphomas in bone marrow biopsies

In this review, we summarise the patterns of bone marrow involvement by small B-cell lymphomas. Both our own experience and the literature reports on the subject show that each subtype of lymphoma can be recognised from a distinct combination of a suggestive growth pattern and a particular cytological composition. A predominantly paratrabecular infiltrate composed of centrocytes is characteristic of follicle centre cell lymphoma. In mantle cell lymphoma, prominent intertrabecular nodules, each consisting of a monotonous proliferation of small to intermediate-sized lymphoid cells with an irregular nucleus, are the most frequent finding. Marginal zone cell lymphoma displays similar intertrabecular nodules, but the infiltrates are rather loose and polymorphic, whereas the lymphoid cells exhibit monocytoid features. Diffuse infiltrates composed of small lymphocytes with clumped chromatin, of plasma cells with Dutcher bodies and of mast cells are observed in most cases of lymphoplasmacytoid lymphoma/immunocytoma. Although chronic lymphocytic leukaemia / small lymphocytic lymphoma can present with a comparable pattern of bone marrow involvement, an interstitial infiltrate of small lymphoid cells is usually observed. A comparable interstitial pattern also prevails in hairy cell leukaemia. This lymphoma subtype, however, can be readily identified by the abundant clear cytoplasm of the neoplastic cells, erythrocyte extravasation and associated abnormalities in the haematopoietic series. Received: 30 August 1999 / Accepted: 1 September 1999