WHO Classification (who + classification)

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Terms modified by WHO Classification

  • who classification system

  • Selected Abstracts

    Development of the WHO Classification of Tumors of the Central Nervous System: A Historical Perspective

    BRAIN PATHOLOGY, Issue 4 2009
    Bernd W. Scheithauer MD
    Abstract The classification of brain tumors has undergone numerous changes over the past half century. The World Health Organization has played a key role in the effort. Four versions of its Classification of Tumours of the Central Nervous System have been published. The present work chronicles their progress, placing emphasis on the historical context of the earliest effort. [source]

    The 2007 WHO Classification of Tumors of the Nervous System: Controversies in Surgical Neuropathology

    BRAIN PATHOLOGY, Issue 3 2008
    Bernd W. Scheithauer MD
    Abstract Controversy surrounds the recent 2007 WHO Classification of Tumours of the Nervous System. A number of nosologic issues remain to be resolved, some a reflection of conceptual disagreement, others the result of inadequate data to permit their definitive resolution. Among these and discussed herein are (i) the nosologic place of highly anaplastic oligoastrocytic tumors, (ii) the forms and significance of microvascular changes in high-grade gliomas, (iii) the makeup of the glioneuronal tumors category, (iv) the subclassification of pineal parenchymal tumors of intermediate type, and (v) the classification of principle forms of mesenchymal neoplasms, specifically hemangiopericytoma and solitary fibrous tumor. These issues and others are the substance of this and an upcoming companion article. [source]

    The unmet treatment need of traumatized anterior teeth in selected secondary school children in Ibadan, Nigeria

    Mojirade Deborah Ajayi
    The aim of this study was to assess the prevalence of damage to permanent anterior teeth in school adolescents, the average duration of trauma and to ascertain the level of the unmet treatment need. A total of 1532 secondary school children between the ages 12 and 19 years participated in the study. They were randomly selected from public secondary schools in five local government areas in Ibadan using a multistage sampling method. Participants were examined with the aid of mouth mirrors and probes under natural light. Traumatic anterior dental injuries were recorded by the same investigator (DMA) according to WHO classification. One hundred and sixty-five participants sustained injuries to their anterior teeth. Their mean age was 15.47 ± 2.09 years, with a male to female ratio of 1.5:1. The commonest cause was fall (78.8%) with road traffic accident being the least (1.8%). The tooth most commonly injured is the upper left incisor (48.0%) closely followed by upper right central (43.1%). Enamel fracture was seen in 46.5% and enamel,dentine in 42.6% of the traumatized teeth. Most (79.4%) of the children sustained injury to one tooth only. Of the participants, only 30 (18.2%) had previous dental consultation while only nine (5.5%) consulted the dentist following the trauma; however, none of the teeth had any form of restoration. Average time elapsed between trauma and dental examination was about 3.5 years. Many participants had had injury for about 2 years before dental examination. In conclusion, there is a high unmet treatment need of traumatized anterior teeth in the study population. [source]

    Clinical investigation of traumatic injuries in Yeditepe University, Turkey during the last 3 years

    Nuket Sandalli
    Abstract,,, The aim of this study was to evaluate etiology, types of traumatic dental injuries, treatment and to determine the incidence of complications according to dental injuries in patients who referred to Yeditepe University, Faculty of Dentistry, Istanbul, Turkey. The study was based on the clinical data of the 161 traumatized teeth in 92 patients. WHO classification slightly modified by Andreasen & Andreasen for dental trauma was used. The causes and localization of trauma, traumatized teeth classification, treatment and complications were evaluated both primary and permanent teeth. The distribution of complications according to diagnosis and treatment of the injured teeth were evaluated. Of 35 (38%) girls and 56 (72%) boys with a mean age 7.6 ± 3.5 (ranging 1,14.2) participated to study and the mean followed up was 1.72 ± 1.28 years (ranging 0.10,3.8 years). From the 161 affected teeth, 69 (42.9%) were in primary teeth and 92 (57.1%) in permanent teeth. The highest frequency of trauma occurred in the 6,12 year age group. Overall boys significantly outnumbered girls by approximately 1:1.6. The most common type of injury in the primary and permanent teeth was seen as luxation (38%) and enamel fracture (20%) of the maxillary central incisors, respectively. Falls were the major sources of trauma both the primary (90%) and the permanent teeth (84%). In the primary dentition, the most common type of soft tissue injury is contusion (62.5%) and in the permanent dentition, it is laceration (49%). The most of the treatment choice was determined as examination only and extraction in primary teeth (58 and 24.6%, respectively) while it was applied as restoration and pulpectomy in permanent teeth (31.5 and 18.5%, respectively). Complications were recorded on 37 teeth (23%) with a most common type of necrosis (10.5%) and dental abscess (7.4%). Necrosis was more frequent in luxation whereas dental abscess were in crown fracture with pulpal involvement in both dentitions. The study showed that boys were more prone to dental traumas than girls. Falls were more frequent trauma type with a high complication risk. It reveals that the time of the immediate treatment showed the important predisposing factors that increase the success of treatment and decrease the risk of complication. The correct diagnosis of dental injuries is more important for eliminating the occurrence of complications. [source]

    Fine-needle aspiration diagnosis of Hodgkin lymphoma using current WHO classification,Re-evaluation of cases from 1999,2004 with new proposals

    Jue-Rong Zhang M.D., Ph.D.
    Abstract With the advent of modern therapy, the differences in prognoses and treatment regimens among different subtypes of Hodgkin lymphoma (HL) have largely vanished. Stage and the presence of systemic symptoms are much more important than histologic subtypes as predictive factors. The current (2001) WHO classification markedly de-emphasizes spatial relationships as critical to the diagnosis of lymphoma and emphasizes cell morphology, immunophenotype, genetic features, and clinical information to define the disease states. This classification, thus, greatly enhances the capability of fine-needle aspiration (FNA) to accurately diagnose HL. We searched all the FNA cases in our institute in years 1999 through 2004 and found 42 cases, for which 13 were primarily diagnosed (31.0%), 2 were recurrent (4.8%), 5 were highly suspicious (11.9%), and 22 were suspicious (52.3%) for HL. On follow-up tissue biopsy, all the primarily diagnosed, recurrent, and highly suspicious cases were confirmed to be HL (100% agreement). For the 22 suspicious cases, 13 were HL (59.1%), 5 were other lymphomas (22.8%), 1 was lymphoma unclassifiable (4.5%), and 3 were reactive processes (13.6%). The effect of immunostains on the diagnosis of HL was examined, and its importance was emphasized. Analysis of demographic data and the distribution of HL subtypes demonstrate that the study sample is representative of the general HL patient population. On the basis of these results, we propose: (1) If the FNA diagnosis of HL is confirmed both by morphology and immunostains, no further tissue confirmation, subclassification and grading is necessary, and appropriate treatment regimens should follow. (2) The nodular lymphocyte predominant HL and classical HL can be differentiated by adequate immunostaining. (3) If a definitive diagnosis cannot be achieved by FNA, a second FNA or a tissue biopsy should be recommended. Diagn. Cytopathol. 2006;34:397,402. © 2006 Wiley-Liss, Inc. [source]

    Normative data of bone mineral density in an unselected adult Austrian population

    S. Kudlacek
    Abstract Background There is increasing evidence that correct interpretation of bone mineral density (BMD) measurements by dual energy X-ray absorptiometry (DEXA) requires a population-specific reference range. We therefore collected data on age-related BMD in a random sample of the normal adult Austrian population to establish an appropriate normative database. Methods We measured BMD by DEXA at five different skeletal sites in 1089 subjects, i.e. 654 females and 435 males, aged between 21,76 years, who had been recruited by 17 centres across Austria. Results Age-related bone loss was observed until age 65 years with significant changes at the lumbar spine (r = ,0·23), total hip (r = ,0·07), trochanter (r = ,0·10), femoral neck (r = ,0·30) and Ward's triangle (r = ,0·40) in the women but only at the femoral neck (r = ,0·23) and at Ward's triangle (r = ,0·40) in the men. When we calculated T scores from the BMD data of the young normal adult study population and used the T score set points according to the WHO classification of osteopenia and osteoporosis, we found that, depending on the skeletal site measured, 7·6,27·4% of the women and 16,41% of the men in our study group had low bone mass, whereas 0·6,2·7% of the female and 0·2,1·0% of the male study population were osteoporotic. However, osteoporosis was indicated in 4,9-fold more females and 5,15-fold more males when we based our estimates on the normative data provided by the manufacturers of the DEXA systems. Conclusion Our data underscore the importance of using a population-specific reference range for DEXA measurements to avoid overdiagnosis of osteoporosis. [source]

    Dextropropoxyphene withdrawal from a French university hospital: impact on analgesic drug consumption

    Sabine Gaubert
    Abstract Dextropropoxyphene is a weak opioid analgesic, widely used as a step 2 analgesic (according to WHO classification) in combination with peripheral analgesics, mainly paracetamol. Recent data have underlined its poor analgesic efficacy (in comparison with paracetamol), risks of serious adverse drug reactions (i.e. hepatic reactions, hallucinations, abuse, withdrawal symptoms, hypoglycaemia), possible lethality after overdose, its risk of accumulation in patients with renal failure or in elderly people and some pharmacokinetic insufficiencies (i.e. different half-lives for dextropropoxyphene and paracetamol). Taking into account these data, the drug committee of the Toulouse University Hospital (France) decided to withdraw dextropropoxyphene from the hospital formulary since 1 June 2005. The aim of our study was to investigate the consequences of this withdrawal by comparing use of analgesic drugs in Toulouse University Hospital before (2004) and after (2006) dextropropoxyphene withdrawal (using defined daily dose for 1000 hospitalization-days as the unit measure). Before withdrawal, dextropropoxyphene (in combination with paracetamol) was the second most used analgesic drug after paracetamol alone. After dextropropoxyphene withdrawal, total consumption of analgesic drugs decreased by 4.6% (2006 vs. 2004). There was a 28% decrease in consumption of step 2 analgesics [with an increase in oral tramadol and a slight decrease in codeine (in combination with paracetamol)]. During the same period, step 1 analgesic consumption increased by 11% (mainly paracetamol) and that of step 3 analgesics slightly decreased (,8%). These results show that dextropropoxyphene withdrawal was not associated with a marked switch in prescriptions towards other analgesic drugs. This paper underlines the interest of a hospital-based drug committee to promote rational drug use. Finally, the present data allow us to discuss putative misuse of dextropropoxyphene. [source]

    Burkitt lymphoma versus diffuse large B-cell lymphoma: a practical approach

    Cristiana Bellan
    Abstract Burkitt Lymphoma (BL) is listed in the World Health Organization (WHO) classification of lymphoid tumours as an "aggressive B-cell non-Hodgkin's lymphoma", characterized by a high degree of proliferation of the malignant cells and deregulation of the c- MYC gene. The main diagnostic challenge in BL is to distinguish it from diffuse large B-cell lymphoma (DLBCL). While in children BL and DLBCL types probably do not differ clinically, and the differential diagnosis between BL and DLBCL may theoretically appear clear-cut, in adults daily practice shows the existence of cases that have morphological features, immunophenotypic and cytogenetics intermediate between DLBCL and BL, and cannot be classified with certainty in these categories. Distinguishing between BL and DLBCL is critical, as the two diseases require different management. This review summarizes the current practical approach, including the use of a large panel of antibodies, and cytogenetic and molecular diagnostic techniques, to distinguish between BL, DLBCL and the provisional category of "B-cell lymphoma, unclassificable, with features intermediate between diffuse large B-cell lymphoma and Burkitt lymphoma", now listed in the updated WHO classification. Copyright © 2009 John Wiley & Sons, Ltd. [source]

    Morphological classification and definition of benign, preneoplastic and non-invasive neoplastic lesions of the urinary bladder

    HISTOPATHOLOGY, Issue 6 2008
    R Montironi
    The morphological classification used in this essay has been based on the most recent World Health Organization (WHO) classification of tumours of the urinary system (i.e. 2004 WHO classification). It includes epithelial abnormalities and metaplasias as well as dysplasias and carcinomas in situ. The lesions are broadly subdivided into two major groups: benign, preneoplastic and non-invasive neoplastic lesions of the urothelium; and benign, preneoplastic and non-invasive neoplastic bladder lesions other than urothelial. Each of these lesions is defined with strict morphological criteria to provide more accurate information to urologists and oncologists in managing patients. There is still debate in the literature as to whether the 2004 WHO system should be the only one to be used and whether the 1973 WHO system should be abandoned. [source]

    The evolving classification of soft tissue tumours: an update based on the new WHO classification

    HISTOPATHOLOGY, Issue 1 2006
    C D M Fletcher
    Tumour classifications have become an integral part of modern oncology and, for pathologists, they provide guidelines which facilitate diagnostic and prognostic reproducibility. In many organ systems and most especially over the past decade or so, the World Health Organization (WHO) classifications have become pre-eminent, partly enabled by the timely publication of new ,blue books' which now incorporate detailed text and copious illustrations. The new WHO classification of soft tissue tumours was introduced in late 2002 and, because it represents a broad consensus view, it has gained widespread acceptance. This review summarizes the changes, both major and minor, which were introduced and briefly describes the significant number of tumour types which have been first recognized or properly characterized during the past decade. Arguably the four most significant conceptual advances have been: (i) the formal recognition that morphologically benign lesions (such as cutaneous fibrous histiocytoma) may very rarely metastasize; (ii) the general acceptance that most pleomorphic sarcomas can be meaningfully subclassified and that so-called malignant fibrous histiocytoma is not a definable entity, but instead represents a wastebasket of undifferentiated pleomorphic sarcomas, accounting for no more than 5% of adult soft tissue sarcomas; (iii) the acknowledgement that most lesions formerly known as haemangiopericytoma show no evidence of pericytic differentiation and, instead, are fibroblastic in nature and form a morphological continuum with solitary fibrous tumour; and (iv) the increasing appreciation that not only do we not know from which cell type(s) most soft tissue tumours originate (histogenesis) but, for many, we do not recognize their line of differentiation or lineage,hence an increasing number of tumours ar placed in the ,uncertain differentiation' category. [source]

    WHO/EORTC classification of cutaneous lymphomas 2005: histological and molecular aspects

    Günter Burg
    It reflects the unique features of lymphoproliferative diseases of the skin, and at the same time it is as compatible as possible with the concepts underlying the WHO classification for nodal lymphomas and the EORTC classification of cutaneous lymphomas. This article reviews the histological, phenotypical, and molecular genetic features of the various nosological entities included in this new classification. These findings always have to be interpreted in the context of the clinical features and biologic behavior. Aim:, To review the histological, phenotypical and molecular genetic features of the various nosological entities of the new WHO/EORTC classification for cutaneous lymphomas. Methods:, Extensive review of the literature cited in Medline and own data of the authors. Results:, The WHO/EORTC classification of cutaneous lymphomas comprises mature T-cell and NK-cell neoplasms, mature B-cell neoplasms and immature hematopoietic malignancies. It reflects the unique features of primary cutaneous lymphoproliferative diseases. Conclusion:, This classification is as much as possible compatible with the concept of the WHO classification for nodal lymphomas and the EORTC classification of cutaneous lymphomas. The histological, phenotypical and molecular genetic features always have to be interpreted in the context of the clinical features and biologic behavior. [source]

    Relative frequency of intra-oral minor salivary gland tumors: a study of 380 cases from northern California and comparison to reports from other parts of the world

    Amos Buchner
    Background:, The relative frequency of individual intra-oral minor salivary gland tumors (IMSGT) is not well documented in the literature. The aim of this study was to determine the relative frequency and distribution of IMSGT in an oral pathology biopsy service and to compare the data with similar studies from different parts of the world. Methods:, Files from the Pacific Oral and Maxillofacial Pathology Laboratory of the University of the Pacific, San Francisco, California served as a source of material for this study. Files were systematically searched for all cases of IMSGT during a 20-year period. Tumors were classified according to the 2005 WHO classification of salivary gland tumors. Results:, IMSGT were identified in 380 (0.4%) cases of 92 860 accessed. This is the largest series of IMSGT from one source reported in recent years. Of the 380 tumors, 224 (59%) were benign and 156 (41%) were malignant. Of the benign tumors, pleomorphic adenoma (PA) was the most common (39.2%), followed by cystadenoma (6.3%), canalicular adenoma (6.1%), ductal papillomas (4.4%), basal cell adenoma (1.6%), and myoepithelioma (1.3%). Of the malignant tumors, mucoepidermoid carcinoma was the most common (21.8%), followed by polymorphous low-grade adenocarcinoma (7.1%), adenoid cystic carcinoma (6.3%), adenocarcinoma, not otherwise specified (NOS; 2.1%), acinic cell carcinoma (1.6%), clear cell carcinoma, NOS (1.0%), and carcinoma ex PA (0.5%). Conclusions:, Studies related to the relative frequency of individual IMSGTs from different parts of the world are difficult to compare because many studies are outdated, the number of cases is small, the list of tumors is limited, and new entities are not included. To determine the true relative frequency, more studies should be conducted, on a large number of cases from one source, by experienced pathologists in the field of salivary gland tumors. [source]

    Revision of the 1992-edition of the WHO histological typing of odontogenic tumours.

    A suggestion
    Abstract Classification of odontogenic tumours is an academic excercise that has developed over the last 150 years. It was not until 1971 when a 5-year collaborated effort, organized by the World Health Organization (WHO), resulted in the first consensus on taxonomy of odontogenic tumours. The appearance of this first authoritative guide to the classification of odontogenic tumours marked the start of an era of quite intensive interest for studying this particular field of oral pathology. An updated 2nd edition of the WHO classification was published in 1992. [source]

    Clear cell ependymoma of the fourth ventricle

    NEUROPATHOLOGY, Issue 4 2004
    Masahito Katoh
    Two cases of clear cell ependymoma (CCE) of the fourth ventricle are reported in a 49-year-old woman with dysphagia and a 59-year-old woman with dizziness and gait disturbance. CCE is a relatively new variant of ependymoma added to the WHO classification of tumors in 1993. Tumor cells display an oligodendroglioma-like appearance with a clear perinuclear halo. Most infratentorial CCE tumors are located in the cerebellum. There are only three cases, including the present two cases, that have been reported to affect the fourth ventricle. [source]

    SHP-1 expression in primary central nervous system B-cell lymphomas in immunocompetent patients reflects maturation stage of normal B cell counterparts

    Yasuo Sugita
    SHP-1 is an important negative regulator involved in signaling through receptors for cytokine/growth factors, and differential patterns of SHP-1 expression in several types of B-cell lymphomas closely resemble the patterns seen in their normal B cell counterparts. In an effort to elucidate the origin of primary central nervous system lymphomas (PCNSL), the present study assessed 32 cases of PCNSL. Tumors were subclassified according to WHO classification and were evaluated by immunohistochemistry for expression of antigens associated with germinal center (GC) (CD10, Bcl-6) and non-GC stages (SHP-1, CD138). Twenty-nine cases showed diffuse large-cell centroblastic morphology, whereas three cases showed diffuse large-cell immunoblastic morphology. The immunophenotypes of PCNSL were as follows: SHP-1+/Bcl-6,/CD10,/CD138, (12 of 32 cases); SHP-1+/Bcl-6+/CD10,/CD138, (15 of 32 cases); SHP-1+/Bcl-6+/CD10+/CD138, (two of 32 cases); SHP-1+/Bcl-6,/CD10+/CD138, (one of 32 cases); and SHP-1,/Bcl-6,/CD10,/CD138, (two of 32 cases). These results indicate that PCNSL might be distinct lymphomas that originate from a late germinal center to an early postgerminal center. [source]

    The World Health Organization classification of malignant lymphoma: Incidence and clinical prognosis in HTLV-1-endemic area of Fukuoka

    Koichi Ohshima
    New insights into the pathogenesis of lymphoid malignancies have been gained through novel genetic, molecular and immunological techniques. A new classification system for lymphoid malignancies, known as the new World Health Organization (WHO) classification, has been proposed recently based on these findings. The relative incidence of the subtypes of malignant lymphoma is known to differ according to geographic location. Adult T-cell leukemia/lymphoma (ATLL) is a human malignancy associated with human T-cell leukemia virus type 1 (HTLV-1), and the Kyushu islands are an HTLV-1 endemic area. To clarify the relationship between the histological classification and prognosis of lymphoid malignancies, we reclassified previous cases in our department and summarized our previous reports using the WHO classification. Of 933 cases of lymphoid malignancies, 471 (50%) were B-cell lymphoma, 396 (42%) T/natural killer (NK)-cell lymphoma and 41 (4%) Hodgkin lymphoma (HL). Analysis of clinical outcome showed favorable prognosis for HL, intermediate for B-cell lymphoma and poor prognosis for T-cell lymphoma. Among B-cell lymphomas, the commonest type was diffuse large B-cell lymphoma (n = 281; 60%). Marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT) was diagnosed in 82 cases (17%), follicular lymphoma in 52 (11%) and mantle cell lymphoma in 24 (5%). Other less common lymphomas were Burkitt lymphoma (n= 9; 2%) and lymphoblastic lymphoma (n = 5; 1%). Using overall survival rates, the various B-cell lymphoma types could be divided into three broad groups for prognostic purposes: (i) low-risk group comprising follicular lymphoma and MALT; (ii) intermediate-risk group comprising diffuse large B-cell lymphoma and Burkitt lymphoma; and (iii) high-risk group comprising mantle cell lymphoma and lymphoblastic lymphoma. Among the T/NK-cell lymphomas, the commonest type was ATLL (n = 191; 48%), followed by peripheral T-cell lymphoma, unspecified (n = 83; 21%), angioimmunoblastic lymphadenopathy with dysproteinemia (AILD) (n = 38; 10%), anaplastic large cell lymphoma (ALCL) (n = 22; 6%). Less common types were lymphoblastic lymphoma (n = 17; 4%), nasal and nasal-type NK/T-cell lymphoma (n = 17; 4%), mycosis fungoides (MF) (n = 9; 2%) and other rare types. With respect to clinical prognosis, T/NK-cell lymphomas fell into three groups: (i) relative low-risk group comprising ALCL, AILD, MF and lymphoblastic lymphoma; (ii) relative intermediate-risk group comprising NK/T-cell lymphoma and unspecified lymphoma; and (iii) extremely high-risk group comprising ATLL. Among the lymphoblastic lymphomas, B-cell type and T-cell type lymphomas exhibited different clinical outcomes. We conclude that the histological, phenotypic and genotypic classification of the new WHO system should be beneficial for the clinical approach to these tumors. [source]

    Prodromal myeloproliferative neoplasms: The 2008 WHO classification,

    Hans Michael Kvasnicka
    The concept of prodromal chronic myeloproliferative neoplasms has been endorsed by the WHO classification implicating a stepwise evolution of disease. Histology of the bone marrow (BM) and borderline to mildly expressed clinical features play a pivotal role for diagnosing prefibrotic-early primary myelofibrosis. By lowering the platelet count for essential thrombocythemia and regarding BM morphology, early manifestations are tackled. Pre-polycythemic stages of polycythemia vera with a low hemoglobin level at onset are diagnosed by positive JAK2V617F mutation status, a low erythropoietin value, and characteristic BM features. The revised WHO classification incorporates hematological, morphological, and moleculargenetic parameters to generate a consensus-based working diagnosis. Am. J. Hematol., 2010. © 2009 Wiley-Liss, Inc. [source]

    Immunohistochemical appearance of HNE-protein conjugates in human astrocytomas

    BIOFACTORS, Issue 1-4 2005
    Kamelija Zarkovic
    Abstract Gliomas are tumors originating from astrocytes, oligodendrocytes or ependimal cells. Those of astrocytic origin are the most widespread of primary brain tumors and account for more then 60% of all CNS neoplasms. The current state of knowledge on the associations between tumor etiology and oxidative stress suggests that environmental factors that cause oxidative stress could also induce and promote cancer, especially in case of hereditary predisposition. Among mediators of oxidative stress, lipid peroxidation product 4-hydroxynonenal (HNE) is of particular relevance in oncology, as it is known to act as a growth-regulating factor and a signaling molecule. The aim of present study was to investigate by immunohistochemistry the presence of HNE-modified proteins in different types of astrocytoma. Our study comprised 45 astrocytic tumors. These tumors were graded in accordance with the WHO classification as diffuse astrocytomas (DA), anaplastic astrocytomas (AA) and glioblastomas (GB), while each group comprised 15 tumors. Slides of paraffin-embedded tumor tissue were stained with hematoxylin-eosin or were prepared for immunohistochemistry with monoclonal antibodies to HNE-histidine conjugate. Positive immunohistochemical reaction to HNE was analyzed semi-quantitatively. HNE positivity was proportional with malignancy of astrocytomas. The weakest presence of HNE-histidine adducts was found in DA, followed by AA and GB. Lowest intensity of HNE immunopositivity was present in tumor cells of almost all DA, predominantly around blood vessels. In malignant variants of astrocytoma, AA and GB, HNE positivity was moderate to strong, and diffusely distributed in all tumors. [source]

    The new World Health Organization classification of haematopoietic and lymphoid tumours: a dermatopathological perspective

    D.N. Slater
    Summary The World Health Organization (WHO) has published a new consensus classification of tumours of haematopoietic and lymphoid tissue, based on recognizable disease entities defined by clinical and scientific criteria. The WHO does not support the use of stand-alone organ-related classifications, such as for skin. The Royal College of Pathologists (London) has adopted the WHO classification in its minimum dataset for the histopathological reporting of lymphoma and this will be used in the National Health Service Skin Cancer Dataset. The purpose of this review is to highlight the principal primary and secondary cutaneous haematopoietic and lymphoid tumours that are defined in the WHO classification. The review also discusses selected problematical areas in the WHO classification relevant to the skin and contains suggestions to encourage a unified approach in the use of the WHO coded summary. These represent an attempt to facilitate future progress and research in the field of cutaneous lymphoma. They are perceived as possible building-blocks for wider discussion and not as alterations to the classification. The WHO classification has been compared with a road map that indicates directions for future clinical and scientific research. [source]

    Reproducibility of Diagnosis and Its Influence on the Distribution of Lung Cancer by Histologic Type in Osaka, Japan

    CANCER SCIENCE, Issue 1 2000
    Seiichiro Yamamoto
    The histologic types of lung cancer cases diagnosed in 1979,1980 (n=799) and 1987 (n=587) were independently reviewed by two pathologists in order to investigate the reproducibility of the diagnosis of the histologic type when the WHO classification (1981) was used. The specimens from 354 surgical cases and biopsy or cytology specimens from 1032 non-surgical cases were reviewed. The inter-observer agreement was 87.9% (k=0.79) for surgical cases and 81.4% (k=0.72) for non-surgical cases. When compared to the original diagnosis, the agreement was 86.8% (k=0.78) for surgical and 86.4% (k=0.79) for non-surgical cases in 1979,1980 and the agreement was 92.8% (k=0.87) for surgical and 89.1% (k=0.83) for non-surgical cases in 1987. By histologic type, no difference in the agreement was observed except for large cell carcinoma. The distribution of histologic types after the review differed only slightly (less than 6%) from the original distribution. This suggests that in Osaka, Japan, the diagnosis based on the WHO classification (1981) had only a limited influence on the distribution of histologic types, and is not a major reason for the changing trends in lung cancer incidence by histologic type. [source]

    The hTERT-protein and Ki-67 labelling index in recurrent and non-recurrent meningiomas

    CELL PROLIFERATION, Issue 1 2005
    L. Maes
    However, a number of these tumours recur even after total resection. The aim of this study is to evaluate the prognostic significance for recurrence of the human telomerase catalytic subunit (hTERT) in the cells of meningiomas. The expression of hTERT-protein can be evaluated by immunohistochemical staining using a monoclonal antibody against hTERT (clone 44F42, NCL-L-hTERT). The interdependence between tumour recurrence and cell proliferation in this study is analysed by Ki-67 immunoreactivity (clone MIB-1). Archival material from 29 non-recurrent and 32 recurrent tumours has been evaluated, including specimens from World Health Organization (WHO) stages I (n = 73), II (n = 2) and III (n = 12). Although the tumours were categorized as benign meningiomas following the WHO classification, recurrence in 22 of 50 cases did not correlate with the tumour stage. For hTERT staining, the following results were found for nucleolar and total nuclear staining, respectively: non-recurrent meningiomas, 2.9% (± 7.7) and 3.0% (± 8.0); recurrent meningiomas at first resection, 16.8% (± 19.7) and 31.6% (± 30.2). Concerning the Ki-67 labelling index (LI): for the group of non-recurrent meningiomas, results were 2.1% (± 1.7) and for the recurrent group at first resection, 1.7% (± 2.0). A significant difference was seen for the hTERT staining (P < 0.001) between the non-recurrent and recurrent meningiomas, whereas no statistical significance was found for Ki-67. In conclusion hTERT-positive meningiomas had a high incidence for recurrence. Ki-67 was a good marker of cell proliferation status of the tumours, but did not correlate with recurrence; thus, hTERT alone seemed to be a potential predictor for recurrence. [source]

    Nucleophosmin (NPM1) mutations in adult and childhood acute myeloid leukaemia: towards definition of a new leukaemia entity,

    Rachel Rau
    Abstract Nucleophosmin (NPM) is a ubiquitously expressed chaperone protein that shuttles rapidly between the nucleus and cytoplasm, but predominantly resides in the nucleolus. It plays key roles in ribosome biogenesis, centrosome duplication, genomic stability, cell cycle progression and apoptosis. Somatic mutations in exon 12 of the NPM gene (NPM1) are the most frequent genetic abnormality in adult acute myeloid leukaemia (AML), found in approximately 35% of all cases and up to 60% of patients with normal karyotype (NK) AML. In children, NPM1 mutations are far less frequent, occurring in 8,10% of all AML cases, and in approximately 25% of those with a NK. NPM1 mutations lead to aberrant localization of the NPM protein into the cytoplasm, thus the designation, NPMc+ AML. NPMc+ AML is seen predominantly in patients with a NK and is essentially mutually exclusive of recurrent chromosomal translocations. Patients with NPM1 mutations are twice as likely as those who lack an NPM1 mutation to also have a FMS-like tyrosine kinase (FLT3) internal tandem duplication (ITD) mutation. NPMc+ AML is also characterized by a unique gene expression signature and microRNA signature. NPMc+ AML has important prognostic significance, as NPMc+ AML, in the absence of a coexisting FLT3-ITD mutation, is associated with a favourable outcome. NPM1 mutations have also shown great stability during disease evolution, and therefore represent a possible marker for minimal residual disease detection. Given its distinctive biologic and clinical features and its clear clinical relevance, NPMc+ AML is included as a provisional entity in the 2008 WHO classifications. There is still much to be learned about this genetic alteration, including its exact role in leukaemogenesis, how it interacts with other mutations and why it confers a more favourable prognosis. Further, it represents a potential therapeutic target warranting research aimed at identifying novel small molecules with activity in NPMc+ AML. Copyright © 2009 John Wiley & Sons, Ltd. [source]

    3462: Epithelial tumours of the lacrimal gland

    Purpose To provide an overview of benign and malignant epithelial neoplasms arising in the lacrimal gland. Methods In the normal orbit, the lacrimal gland is clinically impalpable and is situated in the lacrimal fossa posterior to the superotemporal orbital rim. The gland is not truly encapsulated and is divided into the deep orbital and the superficial palpebral lobes by the levator aponeurosis. The retrospective study of 265 epithelial tumours of the lac¬rimal gland conducted by the Armed Forces Institute of Pa¬thology (AFIP) improved our understanding of the histologic classification and clinical behavior of epithelial tumours of the lacrimal gland. The historic works of Forrest (1954) and Zimmerman (1962) alleviated confu¬sion by applying to epithelial tumours of the lacrimal gland the histopathologic classification of salivary gland tumours. Epithelial tumours originating from the lacrimal gland should be staged according to the 7th Edition of the Tumor Node Metastasis (TNM) system, which is a modification of the World Health Organization (WHO) classification of salivary gland tumours. Results The most common benign epithelial tumour of the lacrimal gland is the pleomorphic adenoma. The most common lacrimal gland carcinomas include adenoid cystic carcinoma, "carcinoma ex pleomorphic adenoma", primary adenocarcinoma & mucoepidermoid carcinoma. The regional lymph nodes include: preauricular, submandibular and cervical lymph nodes. The lung is the most common metastatic site, followed by bone and remote viscera. Conclusion Subtyping & grading of lacrimal gland epithelial tumours requires the latest WHO/AFIP classifications. Staging of these tumours should follow the 7th TNM system. Collection of datapoints is essential to identify biomarkers, which includes only nuclear N23 and MIB-1 at present. [source]

    WHO/EORTC classification of cutaneous lymphomas 2005: histological and molecular aspects

    Günter Burg
    It reflects the unique features of lymphoproliferative diseases of the skin, and at the same time it is as compatible as possible with the concepts underlying the WHO classification for nodal lymphomas and the EORTC classification of cutaneous lymphomas. This article reviews the histological, phenotypical, and molecular genetic features of the various nosological entities included in this new classification. These findings always have to be interpreted in the context of the clinical features and biologic behavior. Aim:, To review the histological, phenotypical and molecular genetic features of the various nosological entities of the new WHO/EORTC classification for cutaneous lymphomas. Methods:, Extensive review of the literature cited in Medline and own data of the authors. Results:, The WHO/EORTC classification of cutaneous lymphomas comprises mature T-cell and NK-cell neoplasms, mature B-cell neoplasms and immature hematopoietic malignancies. It reflects the unique features of primary cutaneous lymphoproliferative diseases. Conclusion:, This classification is as much as possible compatible with the concept of the WHO classification for nodal lymphomas and the EORTC classification of cutaneous lymphomas. The histological, phenotypical and molecular genetic features always have to be interpreted in the context of the clinical features and biologic behavior. [source]