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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↗

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↗

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↗

PubMed2001

Variations of the arterial pattern in the upper limb revisited: a morphological and statistical study, with a review of the literature.

A total of 192 embalmed cadavers were examined in order to present a detailed study of arterial variations in the upper limb and a meta-analysis of them. The variable terminology previously used was unified into a homogenous and complete classification, with 12 categories covering all the previously reported variant patterns of the arm and forearm.

Aged↗

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↗

PubMed2025

CAKL: Commutative algebra k-mer learning of genomics.

Despite the availability of various sequence analysis models, comparative genomic analysis remains a challenge in genomics, genetics, and phylogenetics. Commutative algebra, a fundamental tool in algebraic geometry and number theory, has rarely been used in data and biological sciences. In this study, we introduce commutative algebra k-mer learning (CAKL) as the first-ever nonlinear algebraic framework for analyzing genomic sequences. CAKL bridges between commutative algebra, algebraic topology, combinatorics, and machine learning to establish a new mathematical paradigm for comparative genomic analysis. We evaluate its effectiveness on three tasks-genetic variant identification, phylogenetic tree analysis, and viral genome classification-typically requiring alignment-based, alignment-free, and machine-learning approaches, respectively. Across eleven datasets, CAKL outperforms five state-of-the-art sequence analysis methods, particularly in viral classification, and maintains stable predictive accuracy as dataset size increases, underscoring its scalability and robustness. This work ushers in a new era in commutative algebraic data analysis and learning.

Journal Article↗

PubMed1997

Cell proliferation in salivary gland adenocarcinomas with myoepithelial participation. A study of 78 cases.

We used three markers of cell proliferation mitotic counts, mitotic index and expression of proliferating cell nuclear antigen--to assess the proliferative activity of a series of 78 low-grade salivary adenocarcinomas with myoepithelial participation classified according to: their histological type, the predominant architectural type, and the predominant cytological type. The series included adenoid cystic carcinomas (40), epithelial-myoepithelial carcinomas (19), polymorphous low-grade adenocarcinomas (12) and basal cell adenocarcinomas (7). The proliferation indicators were found to be similar in the first three groups, being significantly lower than in the last. Tumours formed by basal cells had statistically significant higher mitotic indexes than those predominantly composed of clear cells of myoepithelial type and ductal cells. Tubular tumours, irrespective of the histological classification of the neoplasm, had proliferation indexes similar to those found in cribriform neoplasms. Solid tumours, whether formed by ductal or clear myoepithelial-type cells, had higher indexes than the neoplasms with differentiated (cribriform and tubular) patterns. The highest mean values for every proliferation indicator used were found in tumours with solid organization that were predominantly formed by basal cells. These results agree with the hypothesis that cell proliferation is inversely related to neoplastic differentiation. The identification of the prevalent cell phenotype and architecture may extend our knowledge from adenoid cystic carcinoma, whose solid variant carries a worse prognosis, and supports that the usual classification of this group of salivary adenocarcinomas would benefit to be complemented with information on tumour architecture and cellular composition.

Adenocarcinoma↗

PubMed1976

[Epithelial tumors of the liver (histology, histogenesis, classification)].

Under study were 120 epithelial hepatic tumors. The problems of histology, histogenesis, classification, morphogenesis of hepatic tumors are being under consideration from the point of view of modern oncology with due account of tumor progression and its development in tumor field. Various trends of differentiation with isolation of histologic variants of epithelial tumors of the liver have been shown. The histological classification is suggested.

Adenocarcinoma↗

PubMed1986

Immunohistochemical study of small cell lung carcinoma; with special reference to the neuroendocrine markers aromatic L-amino acid decarboxylase and gastrin-releasing peptide.

Forty-seven surgically resected small cell lung carcinomas (SCLC) were immunohistochemically studied by using antibodies to various neuroendocrine and epithelial markers. SCLC was shown to be subdivided into two categories, with and without the immunoreactive neuroendocrine markers aromatic L-amino acid decarboxylase, gastrin-releasing peptide, serotonin, chromogranin A and neurofilament protein. Neuron-specific enolase (NSE) and creatine kinase BB isoenzyme (CK-BB), which are also considered to be neuroendocrine markers, had a tendency to be widely distributed in the SCLC with a neuroendocrine marker, but the immunoreactivity for both NSE and CK-BB varied in the SCLC without neuroendocrine markers. Therefore they were not included in the classification. Epithelial markers keratin, involucrin and epithelial membrane antigen were frequently observed in the SCLC with neuroendocrine markers, but less so in the SCLC without neuroendocrine markers. The data are discussed briefly in relation to "classic and variant" forms of SCLC in vitro and to a recently proposed histological classification of SCLC.

Aromatic-L-Amino-Acid Decarboxylases↗

PubMed1991

Structural and antigenic polymorphism of the 35- to 48-kilodalton merozoite surface antigen (MSA-2) of the malaria parasite Plasmodium falciparum.

Merozoite surface antigen MSA-2 of the human parasite Plasmodium falciparum is being considered for the development of a malaria vaccine. The antigen is polymorphic, and specific monoclonal antibodies differentiate five serological variants of MSA-2 among 25 parasite isolates. The variants are grouped into two major serogroups, A and B. Genes encoding two different variants from serogroup A have been sequenced, and their DNA together with deduced amino acid sequences were compared with sequences encoded by other alleles. The comparison shows that the serological classification reflects differences in DNA sequences and deduced primary structure of MSA-2 variants and serogroups. Thus, the overall homologies of DNA and amino acid sequences are over 95% among variants in the same serogroup. In contrast, similarities between the group A variants and a group B variant are only 70 and 64% for DNA and amino acid sequences, respectively. We propose that the MSA-2 protein is encoded by two highly divergent groups of alleles, with limited additional polymorphism displayed within each group.

Amino Acid Sequence↗

PubMed1998

World Health Organization Classification of lymphomas: a work in progress.

The World Health Organization (WHO) publishes classification handbooks for all neoplastic diseases. The last WHO Classification of leukemias and lymphomas was published in 1976. Since that time, through cytogenetics and molecular biology, it has been shown that many hematopoietic neoplasms are associated with a unique genetic profile. Similarly, the development of widely available and routinely applied monoclonal antibodies has allowed the identification of a unique immunophenotypic profile for most leukemias and lymphomas. These techniques have permitted the recognition of a number of distinct disease entities, and also enhance both diagnostic accuracy and reproducibility. The WHO Classification has been developed under the joint auspices of the European Association for Hematopathology (EAHP) and the Society for Hematopathology (SH). First organized in 1995, the Steering Committee appointed 10 committees covering T-cell and B-cell lymphomas and leukemias, myeloid and histiocytic tumors. The committees were asked to develop a list of diseases within their topic area, and to establish definitions of each disease according to established criteria. The WHO Classification uses the principles of the R.E.A.L. Classification, which defines each disease according to its morphology, immunophenotype, genetic features, postulated normal counterpart, and clinical features. Morphologic and clinical variants of individual diseases are discussed in the text, and their use is optional. The proposed classification was presented at the USCAP meeting in 1997, the site of the first joint meeting of the EAHP and SH. The presentation was followed by an open forum attended by EAHP and SH members. The Steering Committee also appointed a Clinical Advisory Committee to ensure that the classification meets clinical needs, and to resolve questions of clinical significance. The proposed WHO Classification for lymphomas is similar to the R.E.A.L. Classification for lymphomas, with minor modifications and reassessment of provisional categories based on new data since 1994.

B-Lymphocytes↗