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PubMedDate not supplied

Hürthle cell (oxyphilic) papillary thyroid carcinoma: a variant with more aggressive biologic behavior.

The latest World Health Organization International Classification defines papillary thyroid carcinoma by its "follicular cell differentiation...as well as characteristic nuclear changes". However the oxyphilic (Hürthle cell) papillary carcinoma have nuclei which generally resemble the nuclei seen in oxyphilic follicular carcinomas, and such oxyphilic papillary tumors may behave more aggressively than typical papillary cancers. To further characterize these rare tumors, we identified during a 32-year period 22 patients with oxyphilic papillary cancer and compared them with 1,084 patients with typical papillary cancers and 57 patients with oxyphilic follicular cancers treated by the Mayo surgical group during the same time period. Although typical papillary and oxyphilic papillary cancers were comparable with regards to patient age, tumor size and extent, TNM stage, and prognostic score (AGES), there were significant differences. Compared to typical papillary tumors, oxyphilic papillary cancers had fewer neck nodal metastases at primary diagnosis (5% vs 40%, p less than 0.0001), were more often DNA non-diploid (71% vs 21%, p less than 0.001), and after 10 postoperative years had higher rates of both tumor recurrence (28% vs 11%, p less than 0.0001) and cause-specific mortality (1.7% vs 4%, p less than 0.0005). In these four important respects the oxyphilic papillary cancers more resembled the oxyphilic follicular cancers. For oxyphilic follicular cancers, the frequency of initial neck nodal metastases was 7% (cf 5%); 83% of the oxyphilic follicular tumors were non-diploid (cf 71%), and at 10 years postoperatively the tumor recurrence and cause-specific mortality rates were 28% and 18%, insignificantly different from 28% and 17% seen with the oxyphilic papillary cancers.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1996

Pyoderma gangrenosum: classification and management.

Pyoderma gangrenosum (PG) has four distinctive clinical and histologic variants. Some have morphologic and histologic overlapping features with other reactive neutrophilic skin conditions. PG often occurs in association with a systemic disease, and the specific clinical features of the skin lesion may provide a clue to the associated disease. Management of PG depends on its type and severity and usually requires aggressive local and systemic treatment.

Humans↗

PubMedDate not supplied

Feature selection for descriptor based classification models. 2. Human intestinal absorption (HIA).

We show that the topological polar surface area (TPSA) descriptor and the radial distribution function (RDF) applied to electronic and steric atom properties, like the conjugated electrotopological state (CETS), are the most relevant features/descriptors for predicting the human intestinal absorption (HIA) out of a large set of 2934 features/descriptors. A HIA data set with 196 molecules with measured HIA values and 2934 features/descriptors were calculated using JOELib and MOE. We used an adaptive boosting algorithm to solve the binary classification problem (AdaBoost.M1) and Genetic Algorithms based on Shannon Entropy Cliques (GA-SEC) variants as hybrid feature selection algorithms. The selection of relevant features was applied with respect to the generalization ability of the classification model, avoiding a high variance for unseen molecules (overfitting).

Humans↗

PubMed1997

Stevens-Johnson syndrome and toxic epidermal necrolysis are severity variants of the same disease which differs from erythema multiforme.

A new classification, based on the pattern and distribution of cutaneous lesions, separates erythema multiforme major from Stevens-Johnson syndrome. A retrospective re-classification of 76 cases supported the validity of that separation by demonstrating differing causes and pathology. Another prospective international case-control study found differing demographic characteristics and risk factors between erythema multiforme major on the one hand and Stevens-Johnson syndrome or toxic epidermal necrolysis on the other. Erythema multiforme major was mainly related to Herpes virus infection, while Stevens-Johnson syndrome and toxic epidermal necrolysis were associated with drug reactions.

Diagnosis, Differential↗

PubMed2000

Childhood epilepsy with occipital paroxysms: clinical variants in 134 patients.

PURPOSE: In its recent proposal, the Commission on Classification and Terminology of the International League Against Epilepsy classified childhood epilepsy with occipital paroxysms (CEOP) into two syndromes with different predominant seizure types: early onset (Panayiotopoulos type) with eye deviation and ictal vomiting and late onset (Gastaut type) with initial ictal visual symptoms. We documented the clinical features of a large group of patients with CEOP to confirm whether the classification is justified. METHODS: A file review of all patients with partial-onset seizure and interictal occipital spikes referred to our pediatric seizure unit between January 1975 and May 1997 yielded 134 who met the criteria for CEOP. Data were collected with a specially developed protocol and classified according to the two International League Against Epilepsy systems: (a) seizure classification, to test age-specific differences associated with the predominant seizure type, and (b) syndrome classification, to determine whether the clusters of signs and symptoms are sufficiently delineated. RESULTS: Three groups were defined according to the predominant ictal manifestations. Group 1 (visual) consisted of 24 patients (17.9%) with ictal visual symptoms; 19 (14%) of these patients also had overlapping adversive manifestations, either as a separate seizure or as part of the same event (median age at first and last seizure, 7 years 11 months and 10 years). Group 2 (adversive) consisted of 72 patients (53.7%) with tonic eye deviation (median age at first and last seizure, 5 years 2 months and 7 years 2 months). Group 3 (nonvisual, nonadversive) consisted of 38 patients (28.4%) with various seizure spread patterns (median age at first and last seizure, 6 and 7 years 2 months). Two syndromes were identified. The Gastaut type included all 24 patients in the visual group (group 1); seizures were brief and frequent and were diurnal in 83%. The Panayiotopoulos type included all 72 patients in group 2; ictal eye deviation occurred in 100% of the patients and ictal vomiting in 44%; prolonged seizures were observed in 35% and were more frequent in patients who had ictal vomiting than in those who did not (46.8% versus 25%, respectively; p < 0.027). Seizures were infrequent; 24% of patients had a single seizure and 58% had nocturnal seizures. Onset was earlier than for the Gastaut type (p < 0.002). The 38 patients with nonoccipital manifestations did not satisfy the criteria for the complete form of either syndrome. CONCLUSIONS: The most common type of CEOP, the Panayiotopoulos type, is characterized by a cluster of signs and symptoms sufficiently delineated to justify their separate classification from Gastaut-type CEOP, despite the absence of ictal vomiting in more than 50% of the patients.

Age of Onset↗

PubMed2025

Uveal Melanoma and the Lynch Syndrome Tumor Spectrum.

IMPORTANCE: To date, no environmental factors and few therapeutic options are known for uveal melanoma (UM), the most common malignant intraocular primary tumor in adults. Identification of new predisposition factors could lead to better monitoring and possibly improved treatments of patients with UM. OBJECTIVE: To identify new genetic alterations predisposing for UM. DESIGN, SETTING, AND PARTICIPANTS: This was a prospective cohort study conducted at Institut Curie in Paris, France, among 381 consecutive patients diagnosed with UM between July 2021 and February 2023. UM was diagnosed clinically by ophthalmologists, and a senior pathologist confirmed the diagnosis when tumor or biopsy was available. All participants received genetic counseling and consented to extended genetic testing. A panel of 122 genes predisposing to cancer were analyzed by targeted sequencing on germline DNA from these patients. MAIN OUTCOMES AND MEASURES: Frequency of pathogenic variants (PVs) in genes from a targeted panel, with classification of germline PVs done according to the American College of Medical Genetics and Genomics guidelines and the French Unicancer Genetics Group. RESULTS: A total of 79 PVs were identified in 70 participants (41 female and 29 male; mean [SD] age, 60.6 [15.3] years). Among them, 21 were found in clinically relevant genes, with an enrichment in the mismatch repair (MMR) genes, involved in Lynch syndrome, a frequent predisposition to colon and endometrial cancers. This finding suggested MMR germline PVs could also predispose to UM. One tumor was available from a participant carrying a MLH1 germline PV. The tumor exhibited a monosomy 3 with loss of the wild-type allele of MLH1, located on chromosome 3. Loss of expression of MLH1 was observed by immunohistochemistry, and MMR variant signatures SBS6, ID1, and ID2 were identified from the whole-genome sequencing of this tumor, supporting the possibility that MLH1 contributes to the oncogenesis of this UM. CONCLUSIONS AND RELEVANCE: This prospective germline study on patients with UM provided evidence supporting the notion that MMR germline alterations are enriched among patients with UM and may contribute to oncogenesis of UM, and that UM may therefore be a rare tumor manifestation of Lynch syndrome.

Humans↗

PubMed2002

Classification of apocynaceae s.l. according to a new approach combining Linnaean and phylogenetic taxonomy.

A new approach to a nomenclatural system, including elements from both Linnaean and phylogenetic nomenclature, is proposed. It is compatible with the existing Linnaean system, including "standard names" corresponding to principal and secondary ranks, and uses a variant of the definitions from the Phylocode system. A new infrafamilial classification, using this nomenclatural approach, of the Apocynaceae s.l. (i.e., including the Asclepiadaceae) based mainly on analyses of rbcL and ndhF data is discussed. Twenty-one tribes and four rankless taxa are defined.

Apocynaceae↗

PubMed1988

Multilobated non-Hodgkin's lymphoma. A clinicopathologic entity.

Multilobated non-Hodgkin's lymphomas (NHL) have recently been recognized as an NHL variant. During a period of 10 years we observed 30 individuals with NHL in which more than 30% of the malignant cells had a characteristic multilobation. The immunologic phenotype was determined in 14 of these cases. One was of T-cell lineage, and the others exhibited B-lymphoid markers. Sixty-eight percent of the patients presented with extranodal localizations. In the clinical follow-up a complete remission was observed in 78% of patients with a mean duration of 37 months (range, 5 to 120 months). The actuarial survival after 5 years was 45%. From these data we conclude that multilobated NHL are comparable to diffuse, large cleaved-cell NHL of an intermediate grade malignancy according to the Working Formulation or are comparable to the diffuse centrocytic-centroblastic NHL according to the Kiel classification. The neoplastic cells are to be considered as variants of follicle center cells, but the clinicopathologic correlation indicates that multilobated NHL represent a distinct nosologic entity.

Adolescent↗

PubMed1989

[The genetics of rheumatic diseases: genetic basis of the classification of multifactorial diseases].

Examination of the pattern of hereditary predisposition allows a more precise determination of pathogenetic relationships between individual clinical forms and variants of multifactorial diseases (MFD), as well as assessment of the possibilities and approaches to a genetic classification to be made. The construction of genetic classifications is based on the identification of differences in the type of inheritance, the study of the progeny in families where both parents have the same or different forms of the disease, the results of the marker adhesion test, and the genetic correlation coefficients. The study has made use of some clinical forms of rheumatic diseases, whose relationships are a subject of controversy among the clinicians, as splitting phenotypes. Segregation analysis of the selected clinical forms of rheumatic diseases and genetic correlation coefficients obtained within the framework of a quasi-continuous model provide no indication that these forms can be isolated as independent nosologic entities. Possible phenotype splitting into individual subtypes and the potentialities of a marker approach to the construction of genetic MFD classifications are demonstrated, with rheumatoid arthritis associated with HLA antigen Dr 4 taken as an example.

Classification↗

PubMed2003

Epstein-Barr virus-associated anaplastic large cell variant of diffuse large B-cell-type non-Hodgkin's lymphoma with concurrent p53 protein expression.

In the new World Health Organization (WHO) classification of malignant lymphoma, anaplastic large cell lymphoma of B-cell phenotype is classified either as the anaplastic large cell variant of diffuse large B-cell lymphoma or as Hodgkin's lymphoma. A 71-year-old Japanese man developed fever and generalized lymphadenopathy. Biopsy of the right axillary node revealed morphology of malignant lymphoma in which large cells with abundant cytoplasm and pleomorphic nuclei were scattered among small lymphocytes. Immunostaining with various monoclonal antibodies revealed the large cells to be CD79+, CD20/L26+, CD45RO/UCHL-(1-), CD3-, CD10-, CD30+, NPM/ALK-, EMA-, CD15-, and bcl-(2-). Amplification of the J region of the immunoglobulin heavy chain by polymerase chain reaction revealed a single rearranged band. Therefore the diagnosis of anaplastic large cell variant of diffuse large B-cell lymphoma, stage IIIB, was made from the standpoint of the new WHO classification of malignant lymphoma. Biopsy led to findings of Epstein-Barr virus (EBV)-associated lymphoma with positive in situ hybridization results for EBV small RNAs, positive results of immunostaining with EBV latent membrane 1 antibody, and negative results of immunostaining with Epstein-Barr nuclear antigen 2. Results of immunostaining of the mass with p53 antibody also were positive for lymphoma cells. The findings in this case may suggest a close relationship between p53 expression and latent EBV infection.

Aged↗

PubMed1994

Withdrawal akathisia: case reports and a proposed classification of chronic akathisia.

Two patients with akathisia developing only after neuroleptic dosage reduction or withdrawal are described. The literature dealing with tardive or chronic akathisia is reviewed with an emphasis on the existence of variants including the occurrence of symptoms upon withdrawal of the causative drug. A classification of tardive or chronic akathisia syndrome is proposed.

Adolescent↗

PubMed1999

Somatization in Family Practice: Comparing 5 Methods of Classification.

BACKGROUND: It has been suggested that patients with somatoform disorders are high utilizers of medical care, yet interpretation of studies has been difficult because of variant methods of diagnosis. The goal of this study was to compare 5 different methods of classification on the same group of subjects and to examine prevalence rates of somatoform disorders and medical utilization. METHOD: Subjects completed a demographic questionnaire in the physician's office and the somatization section of the Diagnostic Interview Schedule (DIS) by telephone. Subsequently, their medical charts were examined. Using the 5 methods of diagnosis, somatizers were compared with nonsomatizers for level of utilization of medical services. The setting was a medical school-based family practice residency training center. Participants were 119 patients waiting to see their family doctors. The main outcome measures were prevalence of somatization symptoms and chart information (utilization, number of health problems). RESULTS: One subject met the Diagnostic and Statistical Manual (DSM-IV)-based DIS criteria for somatization disorder. With the Bucholz modification for scoring the DIS, 10 subjects were diagnosed with somatization disorder. With the abridged Escobar criteria of 6 symptoms, 7 subjects met diagnostic criteria, while 28 met the criteria for multisomatoform disorder of 3 symptoms, as suggested by Kroenke. The diagnosis of undifferentiated somatoform disorder, requiring only 1 unexplained symptom, was obtained by 94 of the subjects. CONCLUSION: Findings from this study revealed widely divergent prevalence rates of somatoform disorders, depending on methods of diagnosis used. Correlation with rates of medical utilization is suggested as an external criterion for validating diagnostic methods.

Journal Article↗

PubMedDate not supplied

Histological classification of chronic hepatitis.

The 1968 classification of chronic hepatitis distinguished cirrhotic and non-cirrhotic stages, and classified the disease according to the histological degree of disease activity into chronic persistent and chronic aggressive (active) varieties. This seemed appropriate at a time when the aetiology of chronic hepatitis was unknown, and presumed to be auto-immune. Immunosuppressive treatment was reserved for more severe variant of the disease, thus validating the usefulness of the classification. Over the past thirty years, several aetiologies were discovered for chronic hepatitis: the hepatitis viruses B, D, C, and G, side-effects of several therapeutic drugs, and autoimmune hepatitis. This progress created a growing need for a new or adapted classification of chronic hepatitis, since different aetiologies require divergent therapeutic approaches. In 1994, proposals for a new classification of chronic hepatitis came from two international organizations: the International Association for the Study of the Liver and the World Congresses of Gastroenterology. The essence of the proposals includes: primary classification according to aetiology, and determination of disease severity (grading) and stage of progression (staging). Several semiquantitative scoring systems for histological grading and staging of liver biopsies from patients with chronic hepatitis are available. Semiquantitative scoring is useful in the evaluation of new treatment regimens, and in comparing pre- and posttreatment biopsies. It is not indicated in the routine reporting of liver biopsies.

Biopsy↗

PubMed2026

Exploring the Melanoma and Pancreatic Cancer Phenotype of a Potential CDKN2A Founder Variant, I49T (c.146T>C; p.Ile49Thr), in Individuals of Predominantly Mexican Ancestry.

PURPOSE: Pathogenic/likely pathogenic variants (P/LPVs) in the CDKN2A gene cause an increased risk of melanoma (MEL) and pancreatic cancer (PANC). The CDKN2A variant I49T (c.146T>C), reported to be recurrent in Hispanics, has conflicting pathogenicity classifications at laboratories, affecting clinical care. Multiple genetics clinics collaborated to explore cancers associated with I49T. METHODS: Institutional clinical databases were queried for the CDKN2A variants, I49T, known P/LPVs, and c.-2G>A (a benign variant [BV]), and history of PANC and MEL was abstracted. A combination of statistical tests was used to investigate cancer history associations. RESULTS: Data on 203 individuals, with qualifying CDKN2A variants detected on multigene testing between 2012 and 2023, were analyzed (I49T, n = 101; known CDKN2A P/LPVs, n = 57; BV, n = 45). Those with I49T were 91% less likely to have MEL than known CDKN2A P/LPVs (odd ratio [OR] = 0.089 [95% CI, 0.031 to 0.025]; P < .001) and were also less likely to have PANC (OR = 0.45 [95% CI, 0.14 to 1.41]; P = .17). However, mean age at PANC diagnosis for I49T was 56.0 years, significantly younger than known CDKN2A P/LPVs (μ = 71.0 years; P = .026). CONCLUSION: In the largest I49T study to date to our knowledge, MEL was significantly less frequent compared with known CDKN2A P/LPVs. Although a nonsignificant trend was observed for less PANC in I49T than known P/LPVs, individuals with I49T presented with PANC at a significantly younger age than those with known CDKN2A P/LPVs. The presence of I49T in Hispanics of mostly Mexican ancestry supports that it is a founder variant, relevant to understanding cancer risk in a large proportion of Hispanics in the United States.

Humans↗

PubMed2004

Association of the mitochondrial DNA 16189 T to C variant with lacunar cerebral infarction: evidence from a hospital-based case-control study.

A transition of T to C at nucleotide position 16189 in the hypervariable D-loop region of mitochondrial DNA (mtDNA) has attracted research interest for its probable correlation with increasing insulin resistance and development of diabetes mellitus (DM) in adult life. In this article, we present our observations of the positive relationship between this variant and cerebral infarction. Six hundred and one subjects in two groups-one with cerebral infarction (307 cases), the other with no cerebral infarction (294 cases)-were recruited. Their clinical features, fasting blood sugar and insulin levels, and insulin resistance index, were recorded. Patients with cerebral infarction were further categorized into four different subgroups according to the TOAST criteria for stroke classification. The results showed the occurrence of the mtDNA 16189 variant in 34.2% of patients with cerebral infarction and in 26.5% of normal controls. The difference in the occurrence rates between the two groups was statistically significant (P = 0.041). Further studies of the occurrence rate in each stroke subgroup revealed that the variant occurred at the highest frequency in the small vessel subgroup (41.5%). The difference in occurrence rate between this subgroup and the normal controls is highly significant (P = 0.006). These results correlated well with the findings of significantly increased levels of average fasting blood insulin and a higher index of average insulin resistance in the small vessel subgroup of patients harboring this mtDNA variant. Taken together, we suggest that the mtDNA 16189 variant is a predisposing genetic factor for the development of insulin resistance and may be related to various phenotypic expressions in adult life such as development of DM and vascular pathologies involved in stroke and cardiovascular diseases.

Adult↗

PubMed1996

A case of unrelenting pursuit of castration.

OBJECTIVE: Explore the limitations of the classification of body dysmorphic disorder. CLINICAL PICTURE: A chinese male relentlessly pursued castration to relieve painful erections which were never substantiated. The testes and corporaspongiosum had been removed. No psychotic symptom was prominent. TREATMENT: Cognitive therapy and psychotropics were tried. OUTCOME: The remaining corpora cavernosa was removed subsequently. CONCLUSION: The distorted somatic perception and secondary cognitive amplification (painful erections) could represent a variant of body dysmorphic disorder involving internal body image; diagnostic classifications should accommodate such a category.

Adult↗

PubMed1988

Autosomal dominant Emery-Dreifuss syndrome: evidence of a neurogenic variant of the disease.

The first German family with autosomal dominant Emery-Dreifuss syndrome (EDS) is described, with electrophysiologic and myopathologic results providing evidence of a primary neurogenic disease. According to classification of the scapulo peroneal syndrome without cardiomyopathy, we conclude that there are two variants of EDS: one myopathic, the other neurogenic in origin. Therefore, the term Emery-Dreifuss muscular dystrophy should be avoided. Instead, each case of EDS should be classified as myopathic or neurogenic with X chromosome recessive or autosomal dominant inheritance.

Adolescent↗

PubMed2001

Blastic variant of mantle cell lymphoma following interfollicular Hodgkin's lymphoma.

Infrequently, patients are diagnosed with Hodgkin's lymphoma and a morphologically distinct lymphoma. While specific subtypes of lymphomas (including Hodgkin's lymphoma) may present diagnostic difficulties, fine needle aspiration biopsy (FNAB) is sometimes useful in the evaluation and classification of these lymphoproliferative processes. We report a case of the blastic variant of mantle cell lymphoma following Hodgkin's lymphoma, interfollicular variant. A 66-year-old woman with a history of Hodgkin's lymphoma presented with increasing contralateral cervical adenopathy three years after receiving chemotherapy. FNAB with ancillary immunophenotypic characterization identified mantle cell lymphoma, blastic variant. Subsequent excisional biopsy confirmed this diagnosis and also aided in the exclusion of recurrent Hodgkin's lymphoma. In addition to identifying the previously unreported combination of blastic variant of mantle cell lymphoma and Hodgkin's lymphoma, this case emphasizes the utility of FNAB in evaluation of new masses in patient's with a previous diagnosis of Hodgkin's lymphoma.

Biopsy, Needle↗