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PubMed1998

Fournier's gangrene as first presentation of promyelocytic leukemia.

A 50-year-old male is described who presented with Fournier's gangrene as what is probably the first manifestation of a newly diagnosed acute myelogenous leukemia (AML), promyelocytic type or variant type M3 according to the FAB classification. Despite aggressive fluid resuscitation, tuned infusion of vasoactive drugs, appropriate antibiotics and extensive surgical debridement, the patient died within 24 h as a result of irreversible septic shock.

Fournier Gangrene↗

PubMed1999

Ameloblastic fibroma and related lesions: current pathologic concept.

Ameloblastic fibroma (AF) is a true mixed tumor, in which the epithelial and the ectomesenchymal elements are neoplastic. There are two rare variants of AF; granular cell AF and peripheral AF. Ameloblastic fibrosarcoma is a rare tumor, and is regarded as the malignant counterpart of the benign AF. Recent immunohistochemical study using MIB-1 shows labelling indices in the mesenchymal component of the recurrent AF and ameloblastic fibrosarcoma are quite high, in contrast with the conventional AF. Ameloblastic fibrodentinoma is a histologic variant of AF in which dentin or dentinoid tissue has formed, but there is no eveidence that ameloblastic fibrodentinoma exhibit a different biologic behavior than ordinary AF. Ameloblastic fibro-odontoma is a lesion similar to AF, but also showing inductive changes that lead to the formation of both dentin and enamel. Some lesions diagnosed as ameloblastic fibro-odontoma are probably developing odontoma, but the others should not be considered as hamartomatous in nature, since there are rare cases of ameloblastic fibro-odontoma showing true neoplastic behavior, and since the existence of malignant variant is evident. In revised WHO's classification of odontogenic tumors, the terms "ameloblastic fibrodentinoma" and "dentinoma" are used synonymously, however, there are histologic difference between several cases reported previously as "dentinoma" and ameloblastic fibrodentinoma.

Ameloblastoma↗

PubMed2005

Encapsulated columnar-cell carcinoma of the thyroid: a case report.

Columnar-cell carcinoma is a rare form of papillary thyroid carcinoma. It is a biologically aggressive variant, according to the World Health Organization classification, due to its rapid growth, high local recurrence rate, and frequent lung, brain, and bone metastases. However, recent reports indicate encapsulated tumors confined to the thyroid gland are associated with a more favorable prognosis. We report a case of encapsulated columnar-cell carcinoma occurring in the right lobe of the thyroid in a 25-year-old female and discuss the histopathologic features, differential diagnosis, and prognostic factors.

Adult↗

PubMed2002

[Unusual manifestations of autoimmune thyroiditis].

Autoimmune thyroid disease (AITD) is quite common and comprises goitrous and nongoitrous eu- and hypothyroid Hashimoto's Disease with or without preceding thyrotoxicosis, classical hyperthyroid Graves' Disease and its rarer eu- and hypothyroid variants. There is no generally accepted international classification of AITD. Important aspects of the pathogenesis of AITD have been elucidated in the past two decades. AITD may be explained by an excess of either stimulating and/or destructive/blocking immune processes or by a balanced coexistence of various of these pathological autoimmune features. The HLA (DQA1*0501) is involved in determining the susceptibility to AITD. The measurement of antibodies against thyroidal peroxidase and TSH receptor has become the cornerstone in the diagnosis of AITD. Antibodies directed against TSH receptors are stimulating (TSAb) or blocking (TSBAb). In routine measurements they are determined by a radioligand assay which does not distinguish between these two different types of antibodies. A valid interpretation of antibody results is therefore only possible in connection with the clinical findings and the results of thyroid hormone measurements. We present here four unusual cases with AITD which illustrate its complexity and summarize the present state of knowledge on this disease.

Adult↗

PubMed2001

Pathology of low- and intermediate-grade gliomas.

Under the current World Health Organization (WHO) classification, gliomas can be divided into diffuse variants such as astrocytoma, oligodendroglioma, and mixed oligo-astrocytoma versus more discrete subtypes such as pilocytic astrocytoma and other less common entities. These tumors have been assigned histologic grades ranging from I to IV to reflect expected biological behavior. The ever-growing body of literature on genetic alterations of glial neoplasms promises to augment therapeutic and prognostic information in the future. An important example is the 1p and 19q deletions in oligodendrogliomas that recently have been associated with chemosensitivity and prolonged patient survival. This article reviews the pathology of low- and intermediate-grade gliomas, highlighting practical diagnostic and prognostic issues.

Astrocytoma↗

PubMed1982

Classification of the F38 group of caprine Mycoplasma strains by DNA hybridization.

Representatives of groups of mycoplasmas which have antigens in common with Mycoplasma mycoides (as demonstrated by different serological tests) were compared by nucleic acid hybridization. Determinations of DNA homology were performed by filter hybridization as well as hybridization in solution; no differences were revealed between the two methods. Genetic relatedness was not demonstrated between M. primatum and strain F38. The antigenic similarities between strain F38 and the type strain of M. primatum (HRC292) may be due to common epitopes. DNA from strain F38 hybridized with DNA from M. capricolum (California kid) to 80%, but only to about 40% with the two M. mycoides subspecies, a result which can justify the classification of the F38 group as a variant of M. capricolum. The representative strain of bovine serogroup 7 of Leach was equally distant from F38, M. capricolum and the two subspecies of M. mycoides (approximately 60% hybridization).

Animals↗

PubMed2004

Clear cell ependymoma of the fourth ventricle.

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.

Brain Neoplasms↗

PubMed1990

Episodic paroxysmal hemicrania: a further case and review of the literature.

Episodic paroxysmal hemicrania was delineated as a clinical entity only two years ago, separating patients whose attacks remained grouped in bouts lasting weeks, from those who started irregularly and lapsed into chronicity or began and continued in the chronic state. A further case of the episodic variety and a review of the nine previously recorded cases is reported. The division into episodic and chronic variants of paroxysmal hemicrania conforms with the classification of cluster headache. The similarity of the two conditions is emphasised although the response to indomethacin in paroxysmal hemicrania is a special feature.

Adult↗

PubMed1993

Human immunodeficiency virus-associated systemic lymphomas may be subdivided into two main groups according to Epstein-Barr viral latent gene expression.

PURPOSE: We report a pathologic characterization of human immunodeficiency virus (HIV)-associated systemic lymphomas, including the association of Epstein-Barr virus (EBV) in different categories. PATIENTS AND METHODS: Eighty-seven HIV-associated non-Hodgkin's lymphoma (NHL) were classified according to classic NHL classification and a recent description of morphologic variants of high-grade B-cell NHL. Seventy-one cases were immunophenotypically-genotypically characterized, whereas, in 49 representative cases, the association of EBV was assessed by nonisotopic in situ hybridization (ISH) and the immunohistochemical demonstration of latent membrane protein-1 (LMP-1). In addition, 14 Hodgkin's disease (HD) cases, occurring in patients with HIV infection, were investigated for the frequency of LMP-1 expression. RESULTS: Most lymphomas were of B-cell derivation and showed a blastic cell morphology, with (1) small noncleaved cells (SNCCs; 36 cases), (2) large noncleaved cells (10 cases), and (3) immunoblasts, usually polymorphic (12 cases). Moreover, 12 cases were classified as anaplastic large-cell (ALC) Ki-1-positive (Ki-1+) lymphoma. Combined ISH studies (for viral DNA and EBV RNA [EBER]) and immunohistologic demonstration of LMP-1 suggested that there were differences in viral latent gene expression between ALC Ki-1+ or immunoblastic lymphomas (usually EBV+, LMP-1+), and EBV-infected cells of SNCC lymphomas, which did not show LMP-1 expression. A high proportion (10 of 14) of LMP-1+ HD cases was found. CONCLUSION: Differences in EBV association and LMP-1 expression were found between a major group of HIV-associated systemic NHL with blastic cell morphology, including SNCC lymphoma and its variants, and anaplastic cell lymphomas. A proportion of immunoblastic (polymorphic) lymphomas was different in viral latent gene expression from other blastic cell systemic lymphomas. It is concluded that only a group of these lymphomas (most ALC Ki-1+ and HD cases, along with a nonnegligible fraction of immunoblastic lymphomas) seems to be linked etiopathologically to EBV.

Gene Expression Regulation, Viral↗

PubMed2000

[Pleuropulmonary blastoma in children: diagnosis and results of surgery and complex treatment].

This is a report on a retrospective study of experience had with complex treatment of pleuropulmonary blastoma in ten children aged 2-11 years, covering a 27-year period. In all patients diagnosis is made on the ground of clinical symptomatology, imaging methods and histological findings. All patients undergo surgery, as follows: tumor extirpation (n = 3), lobectomy (n = 2) and pneumonectomy (n = 5). Three deaths occur in the early postoperative period (30%). In the remainder postoperative chemotherapy is conducted. Histologically the solid variant (type 3 according to Dehner's classification) is predominant. There are three recurrences (42.8%) among the cases with simple tumor extirpation (2) and lobectomy (1), followed by successful pneumonectomy (two patients) and atypical pulmonary resection (one patient). At long-term follow-up, five patients (50%) are still alive for periods ranging from 1 to 11 years postoperatively. Pleuropulmonary blastoma is a surgical rarity in children. The most important factors for long-term survivorship are both radical surgery, and adequate chemotherapy.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed2002

Developmental anomalies and disabilities associated with hypospadias.

PURPOSE: The incidence of developmental anomalies and disabilities associated with hypospadias is still a matter of controversy and data on this issue are sparse. We describe our experience with and evaluation of developmental anomalies and disabilities in a population in which posterior hypospadias was the most common anomaly. MATERIALS AND METHODS: We reviewed the records of 356 patients who underwent hypospadias repair from January 1986 through April 2000. Collected data included the Barcat classification of the hypospadias anomaly, anatomical penile variants, associated urogenital and extra-urogenital anomalies, and associated disabilities of physical and mental development. RESULTS: Of the 356 patients 234 (65.7%) had posterior, 88 (24.7%) anterior and 34 (9.6%) mid hypospadias. Anatomical variants, including penoscrotal transposition, bifid scrotum and micropenis, occurred predominantly in patients with posterior hypospadias, while penile torsion was present exclusively in the other 2 groups. Inguinal hernia, which was the most common urogenital anomaly, was distributed evenly among the 3 groups with a prevalence rate of 12.4%. Undescended testis in 26 cases (7.3%) was most often associated with posterior hypospadias. In order of frequency associated extra-urogenital anomalies included congenital heart disease in 19 cases (5.3%), musculoskeletal anomalies in 11 (3.1%), anorectal malformation in 6 (1.7%), cleft palate in 3 and other in 7. In 21 patients (5.9%) associated disorders were related to physical and mental development, including growth retardation in 6, cerebral palsy in 2 and psychological disorders that significantly impaired patient bodily function, behavior and performance in 11. Most extra-urogenital anomalies or disorders were associated with posterior hypospadias. CONCLUSIONS: Posterior hypospadias was the most common anomaly in this study. It was associated with a high rate of extra urogenital anomalies, and physical and psychosocial disabilities. The significance of the latter findings with respect to the development of affected patients needs further clarification.

Abnormalities, Multiple↗

PubMed2005

Genotyping of Uruguayan Human adenovirus isolates collected between 1994 and 1998.

Adenoviruses are one of the most frequent causative agents of acute lower respiratory infections in infants and young children. Twenty-three adenovirus isolates from nasopharyngeal aspirates of children hospitalized for acute lower respiratory infections in Uruguay between 1994 and 1998 were studied by restriction enzyme analysis. The genomic analysis showed that 60.9% (n = 14) of isolates belonged to the species Human adenovirus C (HAdV-C) and 31.9% (n = 9) to the species Human adenovirus B (HAdV-B). Whereas some isolates could be classified according to the published profiles into genotype or genomic variant, others displayed migration patterns not allowing classification. Eight isolates (89%) of HAdV-B corresponded to the Ad7h genotype that has been associated with severe and fatal pneumonia and necrotizing bronchiolitis in children in South America. The isolates of HAdV-C showed a great variability in accordance with the data published earlier.

Adenovirus Infections, Human↗

PubMed1991

Histopathologic features of high-grade non-Hodgkin's lymphomas in acquired immunodeficiency syndrome. The French Study Group of Pathology for Human Immunodeficiency Virus-Associated Tumors.

High-grade B-cell non-Hodgkin's lymphomas are observed in 5% to 10% of patients with acquired immunodeficiency syndrome. To describe their histologic subtypes, a group of pathologists was formed. One hundred thirteen cases were reviewed and classified according to the Working Formulation, the updated Kiel classification, and a recent description of morphologic variants of high-grade B-cell non-Hodgkin's lymphoma. Three major types of intermediate- or high-grade lymphomas were observed: (1) large-cell or centroblastic mainly polymorphic lymphomas with a component of immunoblasts (35 cases); (2) immunoblastic lymphomas with plasmablastic and plasmacytic features in most cases (33 cases); and (3) small non-cleaved cell Burkitt's or non-Burkitt's lymphoma (41 cases), with 15 cases fitting typical criteria of Burkitt's lymphoma and 26 heterogeneous cases in which the size and shape of the cells and the presence of plasmablastic features varied. The most frequent pathologic sites of involvement at presentation were the lymph nodes, gastrointestinal tract, bone marrow, brain, oral cavity, and muscles. A comparison between the histologic type and the site of involvement showed that most cases involving lymph nodes, bone marrow, or muscles were small noncleaved cell Burkitt's or non-Burkitt's lymphomas, while those that affected the gastrointestinal tract, brain, and oral cavity were centroblastic or immunoblastic lymphomas with consistent plasmacytic differentiation. In 10 cases, previous persistent generalized lymphadenopathy syndrome was present. In 13 cases, the lymphomatous proliferation was associated with follicular or diffuse hyperplasia seen on the same lymph node biopsy specimen or in another lymph node.

Acquired Immunodeficiency Syndrome↗

PubMed1985

[Teratoma].

The current concepts of the histogenesis of teratoma and criteria for the morphological diagnostics of its histological variants recommended by the WHO International Histological Classification of Tumours are presented.

Adolescent↗

PubMed1994

[An international attempt for standardization on terminology and methodology in hemostasis and thrombosis].

Scientific and Standardization Committee (SSC) of International Thrombosis and Hemostasis has acted its activity since 1955 for establishing international concept on terminology, methodology in the fields of blood platelets, coagulation and fibrinolysis. Among the reports from 15 sub-committee in 1993 meeting, some clinically interesting topics are reported. In von Willebrand factor (vWF) Subcommittee, new classification of von Willebrand disease including new variant of VFW which shows defect on factor VIII binding capacity, is proposed. In Control of Anticoagulation Subcommittee, the necessity of coagulation monitoring during low molecular weight heparin (LMWH) administration was discussed. For prophylaxis use, monitoring is unnecessary except patients having renal failure or high-low body weight. For the treatment of venous thrombosis once or twice monitoring every 10 days would be necessary. In Lupus anticoagulant (LA)/phospholipid dependent antibodies Subcommittee, results of 3rd international survey for LA sent to 38 laboratories in 16 countries including Japan were reported. Most laboratory used APTT and dRVVT simultaneously as screening tests. Sensitivity and specificity of confirmatory test for LA are compared; the best one was Staclot LA and the second was DVVT.

Blood Coagulation Factors↗

PubMedDate not supplied

[The morphological bases of the pathology of the cerebrospinal fluid circulatory system in gunshot wounds of the head].

Pathomorphology of structural elements of the liquor circulation system and its three components (liquor production, circulation, and outflow) in gunshot wounds of the head is discussed. Their role in the development of traumatic diseases of the brain and its complications is analyzed. Classification and characteristics of the main pathomorphological variants of liquor circulation disorders in gunshot wounds of the skull and brain are presented.

Brain↗

PubMed2026

Expert consensus on the reporting and clinical follow up of individuals with incidentally discovered germline RET variants in the UK.

Incidentally discovered pathogenic germline genetic variants refer to the finding of a pathogenic variant in a gene that is unrelated to the reason for the initial test and is not actively sought. Our clinical understanding of the risk of developing a particular medical condition and the required clinical action for a specific pathogenic gene variant is predominantly based on knowledge and information acquired from cases ascertained through a 'phenotype-first approach' rather than in clinically unselected individuals. Therefore, a modified approach is required for incidentally discovered gene variants. Data from large UK and US population-based cohorts have demonstrated that RET variants classified as moderate-risk RET variants as per the American Thyroid Association (ATA) classification have a low penetrance for medullary thyroid cancer and other RET-related conditions (e.g. phaeochromocytoma) and are not associated with excess mortality when identified incidentally in clinically unselected adult individuals. Here, we provide guidance based on multidisciplinary expert consensus opinion for the reporting and subsequent clinical surveillance and management of patients with incidentally discovered RET gene variants in the UK.

Humans↗

PubMed2004

Biology of gastrointestinal stromal tumors.

Once a poorly defined pathologic oddity, in recent years, gastrointestinal stromal tumor (GIST) has emerged as a distinct oncogenetic entity that is now center stage in clinical trials of kinase-targeted therapies. This review charts the rapid progress that has established GIST as a model for understanding the role of oncogenic kinase mutations in human tumorigenesis. Approximately 80% to 85% of GISTs harbor activating mutations of the KIT tyrosine kinase. In a series of 322 GISTs (including 140 previously published cases) studied by the authors in detail, mutations in the KIT gene occurred with decreasing frequency in exons 11 (66.1%), 9 (13%), 13 (1.2%), and 17 (0.6%). In the same series, a subset of tumors had mutations in the KIT-related kinase gene PDGF receptor alpha (PDGFRA), which occurred in either exon 18 (5.6%) or 12 (1.5%). The remainder of GISTs (12%) were wild type for both KIT and PDGFRA. Comparative studies of KIT-mutant, PDGFRA-mutant, and wild-type GISTs indicate that there are many similarities between these groups of tumors but also important differences. In particular, the responsiveness of GISTs to treatment with the kinase inhibitor imatinib varies substantially depending on the exonic location of the KIT or PDGFRA mutation. Given these differences, which have implications both for the diagnosis and treatment of GISTs, we propose a molecular-based classification of GIST. Recent studies of familial GIST, pediatric GIST, and variant forms of GIST related to Carney's triad and neurofibromatosis type 1 are discussed in relationship to this molecular classification. In addition, the role of mutation screening in KIT and PDGFRA as a diagnostic and prognostic aid is emphasized in this review.

Antineoplastic Agents↗