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PubMed1985

Papillary carcinoma.

In addition to a description of the basic criteria for the diagnosis of papillary carcinoma, a review of discussions by all workshop participants on the illustrative cases is presented. Areas of consensus included the following: classification of mixed papillary and follicular carcinomas as papillary, regardless of follicular dominance; recognition of three morphological variants--follicular, encapsulated, and diffuse sclerosing; nonspecificity of individual histological criteria, with the necessity to utilize a combination of characteristic features as guidelines for establishing a diagnosis; citing of nuclear features as probably the most important diagnostic criteria, ie, increased N/C ratio, irregularity in outline, and paleness of staining (ground glass appearance); grading of tumors on the basis of either cytological or architectural characteristics remains of unproven prognostic value. (Gross extent of tumor at the first operation remains the most valuable single prognostic criterion.); defining small carcinomas by size rather than using the imprecise term "occult" with its variable definitions including some clinically evident tumors; classifying as undifferentiated those carcinomas presenting a mixed papillary and anaplastic appearance at the time of the first operation, and retaining the papillary designation for papillary cancers which later undergo dedifferentiation; and recognition that thyroglobulin is a constant and keratin an inconstant tumor cell marker, with the latter not specific for distinguishing papillary carcinomas from follicular carcinomas or from hyperplastic adenomas.

Carcinoma, Papillary↗
PubMed1978

[Cytological recognition of the histological types of lymphogranulomatosis in children].

Examinations of punctates and impressions of lymph nodes from 68 children with primary untreated lymphogranulomatosis permitted to develop the criteria for differential cytological diagnosis of all types and variants of lymphogranulomatosis on the basis of histogenetic analysis and clinico-morphological comparisons, according to histological classification of the WHO. This proved to be possible only after it had been assumed that the original tumor cell must be a semi-stem cell of bone-marrow origin of histiocytic-reticular shoot which normally provides for physiological regeneration of reticular network of the lymph node. It appears that such a cell is a small lymphocyte-like cell with invaginated nucleus, the so-called small cleaved cell.

Child↗
PubMedDate not supplied

Oral Candida infections--a review.

Candida species are the commonest agents of oral mycoses. They cause a variety of diseases including the new variant, erythematous candidosis, which is frequently described in HIV infection. Due to these and other reasons the classification of oral candidosis has been recently revised, and further more new therapeutic regimes have been described. Hence in this article an overview of oral Candida infections is presented with special emphasis on current concepts related to classification and treatment.

Antifungal Agents↗
PubMed1989

Pelizaeus-Merzbacher disease: an X-linked neurologic disorder of myelin metabolism with a novel mutation in the gene encoding proteolipid protein.

The nosology of the inborn errors of myelin metabolism has been stymied by the lack of molecular genetic analysis. Historically, Pelizaeus-Merzbacher disease has encompassed a host of neurologic disorders that present with a deficit of myelin, the membrane elaborated by glial cells that encircles and successively enwraps axons. We describe here a Pelizaeus-Merzbacher pedigree of the classical type, with X-linked inheritance, a typical clinical progression, and a pathologic loss of myelinating cells and myelin in the central nervous system. To discriminate variants of Pelizaeus-Merzbacher disease, a set of oligonucleotide primers was constructed to polymerase-chain-reaction (PCR) amplify and sequence the gene encoding proteolipid protein (PLP), a structural protein that comprises half of the protein of the myelin sheath. The PLP gene in one of two affected males and the carrier mother of this family exhibited a single base difference in the more than 2 kb of the PLP gene sequenced, a C----T transition that would create a serine substitution for proline at the carboxy end of the protein. Our results delineate the clinical features of Pelizaeus-Merzbacher disease, define the possible molecular pathology of this dysmyelinating disorder, and address the molecular classification of inborn errors of myelin metabolism. Patients with the classical form (type I) and the more severely affected, connatal variant of Pelizaeus-Merzbacher disease (type II) would be predicted to display mutation at the PLP locus. The other variants (types III-VI), which have sometimes been categorized as Pelizaeus-Merzbacher disease, may represent mutations in genes encoding other structural myelin proteins or proteins critical to myelination.

Amino Acid Sequence↗
PubMed1986

The Mayer-Rokitansky syndrome: pathogenesis, classification and management.

Agenesis of the vagina in karyotypic female subjects may be accompanied by other defects of the urogenital system. We describe 8 cases that exemplify nearly all variants in the group of müllerian and renal anomalies that we identify as the Mayer-Rokitansky syndrome. We trace the association of system defects to errors of formation of the wolffian body. This structure is the progenitor of the gonad and wolffian duct, which although temporary in the female subject, gives rise to the ureter and is the path finder of the müllerian system. Errors of formation or premature atrophy of the wolffian duct, or intrinsic müllerian organizers lead to the array of anomalies in this syndrome. Vaginal agenesis was found to be associated with müllerian, renal or ovarian defects in numerous embryological combinations. We propose a müllerian classification, and describe the current diagnostic modalities and techniques of surgery.

Abnormalities, Multiple↗
PubMed2005

The Rheology of Blood Flow in a Branched Arterial System.

Blood flow rheology is a complex phenomenon. Presently there is no universally agreed upon model to represent the viscous property of blood. However, under the general classification of non-Newtonian models that simulate blood behavior to different degrees of accuracy, there are many variants. The power law, Casson and Carreau models are popular non-Newtonian models and affect hemodynamics quantities under many conditions. In this study, the finite volume method is used to investigate hemodynamics predictions of each of the models. To implement the finite volume method, the computational fluid dynamics software Fluent 6.1 is used. In this numerical study the different hemorheological models are found to predict different results of hemodynamics variables which are known to impact the genesis of atherosclerosis and formation of thrombosis. The axial velocity magnitude percentage difference of up to 2 % and radial velocity difference up to 90 % is found at different sections of the T-junction geometry. The size of flow recirculation zones and their associated separation and reattachment point's locations differ for each model. The wall shear stress also experiences up to 12 % shift in the main tube. A velocity magnitude distribution of the grid cells shows that the Newtonian model is close dynamically to the Casson model while the power law model resembles the Carreau model. ZUSAMMENFASSUNG: Die Rheologie von Blutströmungen ist ein komplexes Phänomen. Gegenwärtig existiert kein allgemein akzeptiertes Modell, um die viskosen Eigenschaften von Blut wiederzugeben. Jedoch gibt es mehrere Varianten unter der allgemeinen Klassifikation von nicht-Newtonschen Modellen, die das Verhalten von Blut mit unterschiedlicher Genauigkeit simulieren. Die Potenzgesetz-, Casson und Carreau-Modelle sind beliebte nicht-New-tonsche Modelle und beeinflussen die hämodynamischen Eigenschaften in vielen Situationen. In dieser Studie wurde die finite Volumenmethode angewandt, um die hämodynamischen Vorhersagen dieser Modelle zu untersuchen. Um die finite Volumenmethode zu implementieren, wurde die Fluiddynamiksoftware Fluent 6.1 verwendet. In dieser numerischen Studie wurde gefunden, dass die unterschiedlichen hämorheologischen Modelle unterschiedliche Resultate für die hämodynamischen Grössen vorhersagen, von denen bekannt ist, dass sie die Entstehung von Arteriosklerose und die Bildung von Thrombose beeinflussen. Es wurde gefunden, dass die relative Differenz der axialen Geschwindigkeit bis zu 2% und die der radialen Geschwindigkeit bis zu 90% in unterschiedlichen Abschnitten der T-Verbindung beträgt. Die Grösse der Strömungszirkulationszonen und ihrer dazugehörigen Trennungs- und Vereinigungspunkte differieren für jedes Modell. Die Scherspannung an der Wand erfährt ebenfalls eine Verschiebung im Hauptrohr von bis zu 12%. Der Verlauf der Geschwindigkeit auf den Gitterzellen zeigt, dass das Newtonsche Modell mit Bezug auf die Dynamik dem Casson-Modell nahe ist, während das Potenzgesetzmodell dem Carreau-Modell ähnlich ist. R#ENTITYSTARTX000E9;SUM#ENTITYSTARTX000E9;: La rhéologie de l'écoulement sanguin est un phénomène complexe. Présentement, il n'y a pas de consensus universel sur le modèle qui représente la propriété visqueuse du sang. Cependant, parmi la classification générale des modèles non-Newtoniens qui simulent le comportement du sang avec différents degrés de précision, il y a plusieurs différences. Les lois de puissance, les modèles de Casson et Carreau sont des modèles non-Newtoniens populaires et ont un effet sur les quantités hémodynamiques sous plusieurs conditions. Dans cette étude, la méthode de volume fini est utilisée pour explorer les prédictions hémodynamiques de chacun de ces modèles. Pour implémenter la méthode de volume fini, le logiciel de calcul de dynamique des fluides Fluent 6.1 a été utilisé. Dans cette étude numérique, les différents modèles hémorhéologiques tendent à prédire des résultats différents pour les variables hémodynamiques qui sont reconnues comme ayant un impact sur la genèse de l'artériosclérose et de la thrombose. Une différence jusqu'à 2% dans l'amplitude de la vélocité axiale et une différence jusqu'à 90% dans la vélocité radiale sont découverts dans différentes sections d'une géométrie de type jonction en T. La taille des zones de re-circulation d'écoulement et les localisations des points de séparation et de rattachement qui leur sont associées, diffèrent pour chacun des modèles. La contrainte de cisaillement aux parois présente également un déplacement de 12% dans le tube principal. La distribution de l'amplitude de vitesse dans les cellules du maillage montre que le modèle Newtonien est dynamiquement proche du modèle de Casson tandis que le modèle en loi de puissance ressemble au modèle de Carreau.

Journal Article↗
PubMed2004

Myxofibrosarcoma of the breast as an unusual variant of malignant fibrous histiocytoma: report of a case.

Soft tissue sarcomas of the breast account for less than 1% of all malignant breast tumors. The majority of these lesions have an epithelial component and are thus classified as "cystosarcoma phyllodes." All other types of sarcomas are categorized according to the existing histological soft tissue classification. It is difficult to determine the relative frequency of the different types of breast sarcoma because there are wide variations among the reported series. We report a case of myxofibrosarcoma, a variant of malignant fibrous histiocytoma, in a 58-year-old woman.

Breast Neoplasms↗
PubMed1985

Small non-cleaved follicular center cell lymphoma: clinicopathologic comparison of Burkitt and non-Burkitt variants in Finnish material.

A retrospective clinical and histopathological analysis was made of patients with small non-cleaved-type malignant lymphoma according to the classification of Lukes-Collins. Nineteen cases were classified as the Burkitt type and 41 cases as the non-Burkitt type. The non-Burkitt type was more variable cytologically. A bimodal age distribution was seen in both subgroups. One half in both subtypes had an advanced disease (stage III-IV). Lymphadenopathy was slightly more common in the non-Burkitt type. No patient with non-Burkitt's lymphoma had mediastinal involvement (P less than 0.01). Liver and spleen were not involved by the tumor of the Burkitt type (P less than 0.005). Gastrointestinal involvement was seen in both types without differences. No statistical differences between the overall survivals of these subtypes were observed.

Adolescent↗
PubMed2002

The WHO classification of tumors of the nervous system.

The new World Health Organization (WHO) classification of nervous system tumors, published in 2000, emerged from a 1999 international consensus conference of neuropathologists. New entities include chordoid glioma of the third ventricle, cerebellar liponeurocytoma, atypical teratoid/rhabdoid tumor, and perineurioma. Several histological variants were added, including tanycytic ependymoma, large cell medulloblastoma, and rhabdoid meningioma. The WHO grading scheme was updated and, for meningiomas, extensively revised. In recognition of the emerging role of molecular diagnostic approaches to tumor classification, genetic profiles have been emphasized, as in the distinct subtypes of glioblastoma and the already clinically useful 1p and 19q markers for oligodendroglioma and 22q/INI1 for atypical teratoid/rhabdoid tumors. In accord with the new WHO Blue Book series, the actual classification is accompanied by extensive descriptions and illustrations of clinicopathological characteristics of each tumor type, including molecular genetic features, predictive factors, and separate chapters on inherited tumor syndromes. The 2000 WHO classification of nervous system tumors aims at being used and implemented by the neuro-oncology and biomedical research communities worldwide.

Humans↗
PubMedDate not supplied

[Star-gait measured by craniocorpography: pattenrs, classification, physiopathological considerations and clinical utility].

The results of craniocorpographic recordings in the Babinski-Weil test are discussed, focusing on the star-shaped variant. The variants of star-shaped gait are defined as posterior, centered, advanced, forward, extreme, and lateral. In 22 healthy individuals and 60 patients, star-shaped gait was the most common deviation. Extreme star-shaped gait was the most frequent variant in the healthy subjects and the backward variant was the most frequent in the patient group.

Evaluation Studies as Topic↗
PubMed1996

Relation of basal coronary tone and vasospastic activity in patients with variant angina.

OBJECTIVE: To examine the vasoconstrictor response to ergonovine and the vasodilator response to isosorbide dinitrate in spastic and non-spastic coronary segments from 31 patients undergoing serial angiographic follow up of variant angina. METHODS: Coronary angiograms and ergonovine provocation tests were repeated at an interval of 45 (SD 15) months apart. While all 31 patients showed a positive response to ergonovine initially, vasospastic responsiveness persisted in only 16 patients at follow up (group 1) and not in the other 15 patients in whom symptoms of variant angina had resolved (group 2). Mean luminal diameter of 170 normal or near normal entire coronary segments (American Heart Association classification) were measured (a) at baseline, (b) after the administration of ergonovine, and (c) after the administration of isosorbide dinitrate, during both the initial and follow up angiograms using a computer based quantitative angiography analysis system (CAAS II). RESULTS: In vasospastic patients (initial and follow up angiograms in group 1, and initial angiogram in group 2), basal tone was significantly higher in spastic segments compared to adjacent segments or segments in non-spastic vessels. The diagnostic sensitivity and specificity at 20% increase in basal coronary tone for the prediction of vasospasm were 77% and 73%, respectively. CONCLUSIONS: Coronary artery tone may change in proportion to the activity of variant angina over several years. Contrary to some previous reports, the estimation of basal coronary tone may be useful in the assessment of vasospastic activity in patients with variant angina.

Angina Pectoris, Variant↗
PubMed2026

Optical genome mapping enhanced by refined variant interpretation in pediatric acute lymphoblastic leukemia.

Reliable detection of structural variants (SVs) and copy number variations (CNVs) is crucial in the contemporary diagnostics of pediatric B-cell acute lymphoblastic leukemia (B-ALL). However, limitations of commonly used conventional and molecular cytogenetic methods may hinder the accurate genetic characterization of patients. Optical genome mapping (OGM) offers a reliable alternative by enabling high-resolution, genome-wide detection of CNVs and SVs. Chromosomal aberrations were screened using OGM in 51 children with B-ALL. The results were compared with those of karyotyping, fluorescence in situ hybridization (FISH), digital multiplex ligation-dependent probe amplification (digitalMLPA), and targeted RNA sequencing (RNA-seq). OGM data showed high congruency with karyotyping and FISH findings, detecting clinically relevant variants beyond G-banding results and unraveling a complex KMT2A fusion undetected by FISH. Gene fusions involved in complex ETV6::RUNX1 translocations, but not detected by RNA-seq, were confirmed using FISH. Normalization of OGM copy number values with DNA-index-improved concordance with FISH-derived copy numbers in near-tri/tetraploid cases. In the peripheral regions of OGM variants (fringe-zones), a novel evaluation strategy called 'FriZone' was applied, which significantly improved the concordance between OGM and digitalMLPA. In addition, a co-segregation analysis revealed strong associations between ETV6::RUNX1 fusion and deletions of ETV6, RAG2, and NR3C2. OGM uncovered complex rearrangements undetected by widely used methods in 15% of cases, improving genetic classification and risk stratification in 10% of the patients. The FriZone analysis and normalization by DNA-index provide a refined, more accurate approach to OGM variant interpretation, facilitating the efficient application of OGM in clinical diagnostics. © 2026 The Author(s). The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Humans↗
PubMed2003

Soft learning vector quantization.

Learning vector quantization (LVQ) is a popular class of adaptive nearest prototype classifiers for multiclass classification, but learning algorithms from this family have so far been proposed on heuristic grounds. Here, we take a more principled approach and derive two variants of LVQ using a gaussian mixture ansatz. We propose an objective function based on a likelihood ratio and derive a learning rule using gradient descent. The new approach provides a way to extend the algorithms of the LVQ family to different distance measure and allows for the design of "soft" LVQ algorithms. Benchmark results show that the new methods lead to better classification performance than LVQ 2.1. An additional benefit of the new method is that model assumptions are made explicit, so that the method can be adapted more easily to different kinds of problems.

Costs and Cost Analysis↗
PubMed2026

Transverse testicular ectopia with fused vas deferens: A systematic review.

BACKGROUND: Transverse testicular ectopia (TTE) with fused vas deferens is an extremely rare anomaly, often diagnosed intraoperatively. Current TTE classifications do not address internal ductal variations, limiting surgical guidance. OBJECTIVE: To systematically review cases of TTE with fused vas deferens, summarize presentation, operative strategies, outcomes and identify patterns that highlight the need for classification refinement. METHODS: A PRISMA 2020-compliant systematic review (PROSPERO; CRD420251247785) was performed across PubMed, ScienceDirect and citation of included articles through December 2025. Case reports and series confirming fused vas deferens were included. Data extracted comprised demographics, presentation, imaging, surgical approach, and outcomes. Quality assessment used JBI checklists. RESULTS: 12 studies (16 patients) were included. Most presented with unilateral inguinal hernia (62%) and contralateral undescended testis (68%); 81% were diagnosed intraoperatively. Anatomical patterns included common/proximal fused vas (87%), Y-shaped fusion (6%), and long-loop vas (6%). Trans-septal orchidopexy was the preferred approach, with preservation of vas integrity. Postoperative outcomes were favorable; long-term follow-up was limited. CONCLUSION: TTE with fused vas deferens represents a distinct variant requiring careful intraoperative recognition. We propose a Type IV TTE category for internal ductal fusion to guide surgical planning and classification refinement. Further accumulation of case-based evidence may help clarify its anatomical patterns and operative implications.

Humans↗
PubMed1982

North american Burkitt-type ALL with a variant translocation t(8;22).

A variant translocation, t(8;22) (q24;q12), was found in bone marrow (BM) and long-term cultured peripheral blood (PB) cells obtained from an American boy with Burkitt-type acute lymphoblastic leukemia (ALL-L3, French-American-British classification). Surface marker studies revealed a monoclonal immunoglobulin A (sIgA) with a lambda chain (74%) on the PB cells in a sample containing 74% blast cells. A table summarizing the cases with variant translocations in Burkitt diseases [Burkitt lymphoma (BL) and ALL-L3] is presented, and review of the published data indicates that, generally, the survival of patients with t(8;22)-type BL and ALL-L3 is short and comparable to that of patients with the more common translocation, t(8;14). There appears to be no relationship between t(2;8) or t(8;22) and a specific heavy-chain sIg. The karyotypes of the BM cells and those of the long-term cultured PB cells, though retaining t(8;22), differed from each other. Chromosomal analyses using cells from long-term culture may reveal karyotypic changes in addition to those seen on direct analysis. The key karyotypic anomaly in Burkitt-type diseases appears to be the breakage of chromosome #8 at band q24.

Burkitt Lymphoma↗
PubMed2005

Clinicopathologic and molecular correlations of necrosis in the primary tumor of patients with renal cell carcinoma.

BACKGROUND: The presence of histologic necrosis in the primary tumor of patients with renal cell carcinoma (RCC) has been suggested to be an important predictor of survival. The authors investigated the relation of tumor necrosis to other clinicopathologic factors known to be important prognostic indicators for patients with RCC. METHODS: The records of 311 patients undergoing treatment for RCC were evaluated for basic clinicopathologic information including TNM classification, nuclear grade, Eastern Cooperative Oncology Group (ECOG) performance status (PS), disease recurrence, and survival. The presence and extent of histologic necrosis of the primary tumors was recorded and correlated with clinicopathologic factors, carbonic anhydrase IX and Ki-67 expression, disease recurrence, and survival. RESULTS: The presence of necrosis in the primary tumor of patients with RCC compared with patients with RCC without necrosis was associated with higher T classification (P < 0.0001), the presence of lymph node disease (P = 0.009), the presence of metastases (P < 0.0001), higher grade (P < 0.0001), greater mean tumor size (P < 0.0001), an ECOG PS score > or = 1 (P = 0.007), higher University of California-Los Angeles Integrated Staging System (UISS) category (P < 0.0001), and higher Ki-67 expression (P < 0.0001). The extent of necrosis in the primary tumor was associated with the presence of lymph node disease (P = 0.009) and the presence of metastases (P < 0.0001), and correlated with higher T classification (sigma = 0.31, P < 0.0001), poorer ECOG PS (sigma = 0.18, P = 0.002), higher grade (sigma = 0.33, P < 0.0001), greater tumor size (sigma = 0.40, P < 0.0001), higher UISS category (sigma = 0.37, P < 0.0001), and higher Ki-67 staining (sigma = 0.32, P < 0.0001). Patients with the presence of necrosis in the primary tumor demonstrated a lower 5-year disease-specific survival compared with patients without necrosis in the primary tumor (36% vs. 75%; P < 0.0001). Multivariate analysis demonstrated that T classification (P < 0.0001), distant metastases (P < 0.0001), and ECOG PS (P < 0.0001) were independent predictors of DSS, whereas the presence of necrosis was not (P = 0.1100). Substratification into localized and metastatic disease demonstrated that the presence of necrosis was an independent predictor of survival in patients with localized (P = 0.025), but not metastatic (P = 0.44), disease. The extent of necrosis was not an independent predictor of survival (P > 0.05). Patients with the presence of necrosis in the primary tumor had a lower 5-year disease recurrence-free rate compared with patients without the presence of necrosis (62% vs. 92%, P < 0.0001). CONCLUSIONS: The presence of necrosis in the primary tumor was associated with adverse prognostic factors such as high T classification, presence of lymph node disease and metastases, high grade, large tumor size, and poor ECOG PS. The extent of necrosis was found to be associated with the presence of lymph node disease and metastases and correlated with higher T classification, higher grade, greater tumor size, poorer ECOG PS, and higher UISS category. The presence of this histologic variant was an independent predictor of poor survival in patients with localized, but not metastatic, disease. In addition, Ki-67 expression served as a valuable surrogate marker for the presence of histologic tumor necrosis.

Adenocarcinoma, Clear Cell↗
PubMed1988

Two new esterase D (ESD) variants revealed by isoelectric focusing in agarose gel.

Using isoelectric focusing in thin-layer agarose gel (AGIF) with the narrow pH range of 4.5-5.4, a high resolution of esterase D (ESD) isozyme banding patterns has been achieved. Some variant phenotypes which could not be distinguished from common ESD types by conventional electrophoresis have shown different patterns after AGIF. The IEF method permitted the distinction of two further variants in the ESD system, tentatively named ESD Rehren and ESD Ravensburg. We recommend, therefore, that for the classification of ESD phenotypes a high resolution IEF technique should be used.

Alleles↗