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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↗
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↗
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↗
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↗
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↗
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 (&#x3bc; = 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↗
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↗
PubMed2000

Haemolysin-deficient variants of Streptococcus pyogenes and S. dysgalactiae subsp. equisimilis may be overlooked as aetiological agents of pharyngitis.

Variants of large colony beta-haemolytic Lancefield group A, C and G streptococci that are non-haemolytic or alpha-haemolytic on sheep blood agar have been detected in clinical specimens due to their enhanced haemolytic activity when grown on a new selective and differential blood agar medium containing colistin, nalidixic acid and pH 7.5-adjusted PIPES buffer (CNA-P). The large colony Lancefield group C and G isolates were identified as Streptococcus dysgalactiae subsp. equisimilis by API 20 Strep classification and 16S rDNA profiling. The haemolytic activity of these variants on various blood agar media, including CNA-P, was closely similar to that of known streptolysin S-defective mutants of S. pyogenes and was blocked by addition of cholesterol, a specific inhibitor of the streptolysin O family of haemolysins. As haemolysin variants could be detected in large numbers in cultures from patients with clinical symptoms of pharyngitis it is suggested that they may function as primary pathogens in such infections. The high frequency with which haemolysin variants were isolated from clinical specimens during a 3-month trial (3%, 13% and 10%, respectively, of group A, C and G streptococcal isolates) indicated that a substantial proportion of streptococcal infections may go undetected if only conventional sheep blood agar media are used in clinical laboratories for the detection of beta-haemolytic streptococci. As haemolysin variants have been implicated in the development of serious streptococcal sequelae, further investigation of the full extent of their contribution to streptococcal disease is indicated.

Antigens, Bacterial↗
PubMed1980

Ovarian neoplasms resembling sex cord tumors with annular tubules.

A clinicopathologic analysis of 6 patients with ovarian neoplasms resembling sex cord tumors with annular tubules (SCTAT) was performed. The patients' ages ranged from 20 to 43 years. Most had signs and symptoms of estrogenic hormonal imbalance; none had evidence of the Peutz-Jeghers syndrome. The tumors were unilateral in all cases and, except for one lesion of microscopic size, were from 3 to 18 cm in greatest dimension. One tumor was combined with a germinoma. Surgery alone was the primary mode of therapy in all cases. Lymph nodal metastases developed in 2 patients 7.5 and 10.5 years postoperatively. They are the first documented examples of malignant behavior recorded. At the time of last known contact, all patients were alive without demonstrable tumor for intervals from 1.5 to 16.3 years (mean, 7.8 years) after initial treatment. While the annular patterns of growth have often been attributed to Sertoli cell differentiation, histologic and cytologic features of granulosa cell tumor were observed in areas of the primary tumors and in metastatic lesions. True lumen formation was never observed in the so-called tubules. We propose classification of SCTAT as a distinctive annular and membranous variant of granulosa cell tumor in view of the morphologic similarities and comparable clinical behavior of these two neoplasms.

Adult↗
PubMed1999

Selected cutaneous vascular neoplasms. A review.

This article reviews the pathology of benign, borderline, and malignant vascular neoplasms of the skin. The classification of vascular lesions of childhood is presented. Defined variants of hemangioma (including sinusoidal, microvenular, glomeruloid, epithelioid, and targetoid hemosideric hemangioma, as well as acquired tufted hemangioma and angiofibroma) are discussed. Borderline hemangioendotheliomas are classified. Kaposi sarcoma is reviewed with an update on the role of human herpesvirus type 8 in its pathogenesis. Angiosarcoma and acquired progressive lymph-angioma are also discussed.

Biopsy, Needle↗
PubMed2000

Histologic subtyping and malignancy assessment of cutaneous squamous cell carcinoma.

BACKGROUND: Squamous cell carcinomas (SCCs) of the skin have a wide range of histologic subtypes and there are indications of differences in prognosis. OBJECTIVE: The morphologic variety of SCCs with respect to its biological behavior and the further course of disease is analyzed, with emphasis on histopathologic criteria, briefly quoting the main clinical and pathogenetic aspects. METHODS: Referring to the international tumor classification of the World Health Organization, histologically different carcinoma variants are presented and discussed, based on a review of the literature regarding each subtype, and also including the desmoplastic SCC type. RESULTS: Histologically, common invasive SCCs are most frequently found, while metastases mainly occur in tumors of high thickness and poor differentiation. The immature spindle cell carcinoma type resembles sarcoma and may grow rapidly with an aggressive clinical course. Lymphoepithelioma-like carcinoma of the skin is extremely rare and its histogenesis remains to be elucidated. Thus far, one case with metastasis and lethal outcome has been reported. As details determining the progression ability have so far only been scanty and partially contradictory, more investigations are necessary, especially for acantholytic SCCs and invasive SCCs developing from Bowen's disease, whereas verrucous carcinomas can be categorized as low malignancy neoplasms. Desmoplastic SCCs, especially with large tumor thickness, should be separated from other SCC subtypes due to their high risk of local recurrence and metastatic spread. CONCLUSION: The future outcome of SCCs of the skin is significantly influenced by their histologic grade and tumor thickness. In addition, subtyping represents another valuable histopathologic tool for improving the assessment of malignancy.

Bowen's Disease↗
PubMed1998

The role of alternative splicing of the adhesion molecule, CD44, in lymphoid malignancy.

AIM: To investigate the expression of CD44 isoforms containing variant exon 6 (v6) in a well characterised cohort of patients with non-Hodgkin's lymphoma (NHL) and chronic lymphocytic leukaemia (CLL), and to correlate this with phenotype and disease course. METHODS: Cryostat sections of OCT embedded diagnostic nodal material from NHL patients and cryopreserved mononuclear preparations from CLL patients were used as sources of RNA. After reverse transcription, PCR was carried out with amplimers positioned at either side of the variant exon insertion site to amplify all possible CD44 isoforms. Those isoforms containing v6 were identified after Southern blotting and hybridisation with a radiolabelled oligonucleotide. RESULTS: Of 32 NHL samples analysed, 16 did not express CD44 isoforms containing v6, six expressed an isoform containing exon v6 alone, and 10 expressed v6 long isoforms which contained exon v6 in addition to other variant exons. These data did not correlate with lymphoma classification, disease staging, or the presence or absence of extranodal disease. However, those patients expressing v6 long CD44 isoforms had a worse overall survival than those that did not. The plateau of the survival curves was 50% compared with 82%. No v6 long isoforms were detected in the 21 CLL samples investigated. CONCLUSIONS: The expression of v6 long CD44 isoforms is associated with aggressive disease in NHL, independent of grade, stage, or presence of extranodal disease.

Alternative Splicing↗
PubMed1990

A new von Willebrand factor (vWF) defect in a patient with factor VIII (FVIII) deficiency but with normal levels and multimeric patterns of both plasma and platelet vWF. Characterization of abnormal vWF/FVIII interaction.

The patients with inherited bleeding diathesis related to quantitative, structural, and/or functional abnormalities of von Willebrand factor (vWF) are said to have von Willebrand's disease (vWD). We report here the clinical and laboratory features of a 50-year-old woman with a life-long history of excessive bleeding. Her particular laboratory data are factor VIII (FVIII) deficiency, subnormal bleeding time, and the presence of all plasma and platelet vWF multimers in normal amounts. Infused with FVIII/vWF concentrate, she showed a persistent increase in FVIII that led us to discard hemophilia A carrier or "acquired hemophilia" diagnoses. vWF devoid of FVIII purified from normal and patient's plasma by immunoaffinity on anti-vWF monoclonal antibody (MoAb) was immobilized onto polystyrene tubes that were further incubated with purified normal FVIII. The bound FVIII was evidenced using radiolabeled anti-FVIII MoAb. The data showed that the patient's vWF, in contrast to vWF purified from normal plasma, was unable to bind FVIII. Furthermore, no inhibitor of FVIII/vWF interaction was evidenced in incubating purified normal vWF with the patient's plasma before the addition of FVIII and anti-FVIII MoAb. These results support the concept that the bleeding diathesis of this patient appears to be due mainly to her abnormal vWF preventing FVIII/vWF interaction. This abnormality, which is not yet described in present classification of vWD, could be considered as a new variant of vWD.

Factor VIII↗
PubMedDate not supplied

Von Willebrand factor and von Willebrand's disease: a complex protein and a complex disease.

Von Willebrand factor is a complex protein which is important in several ways for normal hemostasis. Von Willebrand's disease results when there is either a quantitative or qualitative disorder of von Willebrand factor. In this review, the structure and function of von Willebrand factor are discussed. Additionally, the current laboratory and clinical classification of von Willebrand's disease and closely related variants are outlined.

Factor VIII↗