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PubMedDate not supplied

Cytodiagnosis of classic lobular carcinoma and its variants.

The well-known cytologic features of lobular carcinoma traditionally consist of modest cellularity and small, atypical cells lying singly or in small groups. However, lobular carcinoma is a common pitfall in the cytodiagnosis of breast lesions. Knowledge of its varied histologic appearance can help to prevent diagnostic difficulties. Among 55 consecutive cases of breast needle aspirates with histologic follow-up, 9 lobular carcinomas were identified. The surgical material was examined for the following histologic variants: (1) classic, (2) solid, (3) alveolar, and (4) mixed; it was correlated with the cytologic findings. Pure, classic lesions were the most likely cause of false-negative diagnoses. Two of nine lobular carcinomas were diagnosed as benign due to scant cellularity and cell smallness. Four of nine were cytologically misclassified as ductal type due to more abundant cellularity and larger cells. This could be attributed to the predominant alveolar or solid patterns present in three cases. Only three of nine were accurately classified as lobular carcinoma, and all had a significant classic histologic element. Another important feature that is highly suggestive of lobular carcinoma is the presence of cytoplasmic vacuoles. They were overlooked in three of four cases. This study suggested that the traditional cytologic features of lobular carcinoma are present only in tumors with a predominantly classic histologic pattern. Awareness of the variant patterns and their cytologic features, including more abundant cellularity, larger cells and clusters, and cytoplasmic vacuoles, will aid in correct classification.

Biopsy, Needle↗
PubMed2001

[Immunological classification of 112 adult acute leukemia patients].

OBJECTIVE: To explore the criteria and significance of immunological classification in adult acute leukemias. METHODS: One or two color monoclonal antibodies directly labeled with immunofluorescence were used to analyse the surface and cytoplasma antigens by flow cytometry, and an antibody integral system was developed for the immunologic classification. RESULTS: One hundred and twelve adult acute leukemia cases were detected. (1) The undifferentiated phenotype account for 0.9%, simple 51.8%, variant 38.4% and mixed lineage 8.9%. (2) The abnormal expressions of antigen in variant and mixed lineage phenotype were CD7, CD33, CD10, CD13, CD19 and CD20, by order of decreased level. CONCLUSION: The strict, numerical diagnostic criteria was very convenient and useful for immunophenotyping of adult acute leukemia.

Acute Disease↗
PubMedDate not supplied

Myotonia levior: contribution to the nosography.

Two family are described affected by a mild myotonic syndrome, characterized by almost exclusively presence of myotonic phenomenon, in absence of symptoms as muscular weakness, hypotrophy or hypertrophy ("myotonia levior"). The nosographic classification of this disease in the congenital myotonias is today uncertain, and it could be a case of a low expressivity variant of the dominant form (Thomsen disease), or the heterozygotic phenotype of the recessive form (Becker disease). Family history, clinical and electrophysiological data obtained in the patients seem to support first hypothesis, providing an useful element for a correct genetic counselling in these cases.

Adult↗
PubMed1993

[Pathologic conclusion about the cause of death].

The author compares the rules of the pathology diagnosis formulation with the requirements of the International classification of diseases and suggests ending the pathology epicrisis with a separate paragraph "Pathology conclusion about the cause of death". 8 variants of such conclusion are suggested taking into consideration different construction of diagnosis (monocausal, bicausal, multicausal).

Cause of Death↗
PubMed1995

A distinct subtype of M4/M5 acute myeloblastic leukemia (AML) associated with t(8:16)(p11:p13), in a patient with the variant t(8:19)(p11:q13)--case report and review of the literature.

Acute myeloblastic leukemia (AML) with t(8:16) or its variant t(8:V) has been rarely reported. A high proportion of patients are infants and children, often with a bleeding tendency and disseminated intravascular coagulopathy (DIC). Only one-third of the de novo patients remain in the first complete remission following multiagent chemotherapy and bone marrow transplantation (BMT). Morphocytochemically, the disorder is classified as an M5, M4, or M4/M5 variant. In the presented case, with the variant t(8:19)(p11:q13), comprehensive light and electron microscopic blast cell characterization showed monocytic and granulocytic features compatible with the M4 subtype (on the monocytic predominance range of the French-American-British classification scale). Although hemophagocytosis, one of the hallmarks of the disease, was rare in our patient, numerous autophagic vacuoles were present. Immuno- and genotyping showed a myelomonocytic phenotype with no evidence of early progenitor antigen expression or mixed leukemia. These results and those of previous reports support the high specificity of t(8:16) or its variants to the unique M4/M5 type leukemia and the role of a gene on 8p11 in this specific transformation.

Adolescent↗
PubMed2004

Therapeutic options for variant renal cancer: a true orphan disease.

Variant or nonclear cell renal cell cancer is a rare disease constituting only approximately 5% to 8% of the metastatic renal cell cancer population. Pathological criteria for the three main variant subtypes, papillary, chromophobe, and collecting duct, have been specified. Nonetheless, there may be subtypes within these variants, many poorly differentiated tumors cannot be reliably classified, and expertise in recognizing specific subtypes is not widespread. Expression analysis and other molecular techniques are beginning to clarify and standardize the pathological classification scheme. Because these classifications are relatively new and the number of patients with any one subtype is limited, little is known about appropriate therapies for patients with metastatic disease. Retrospective series strongly suggest that immunotherapy is not effective in any nonclear cell subtype. Case reports suggest that cytotoxic chemotherapy used for transitional cell cancers may be helpful in patients with collecting duct cancers. A central registry of patients with variant renal cell cancer should be created in which response to various therapies is recorded. Such a registry could provide support for a more formal multi-institutional study investigating a specific drug or regimen.

Carcinoma, Renal Cell↗
PubMed1997

Induction of decision trees and Bayesian classification applied to diagnosis of sport injuries.

Machine learning techniques can be used to extract knowledge from data stored in medical databases. In our application, various machine learning algorithms were used to extract diagnostic knowledge which may be used to support the diagnosis of sport injuries. The applied methods include variants of the Assistant algorithm for top-down induction of decision trees, and variants of the Bayesian classifier. The available dataset was insufficient for reliable diagnosis of all sport injuries considered by the system. Consequently, expert-defined diagnostic rules were added and used as pre-classifiers or as generators of additional training instances for diagnoses for which only few training examples were available. Experimental results show that the classification accuracy and the explanation capability of the naive Bayesian classifier with the fuzzy discretization of numerical attributes were superior to other methods and estimated as the most appropriate for practical use.

Artificial Intelligence↗
PubMed2005

Classification of A1- and A24-supertype molecules by analysis of their MHC-peptide binding repertoires.

At the functional level, the majority of human leukocyte antigen (HLA) class I MHC variants can be classified into about ten different major groups, or supertypes, characterized by overlapping peptide binding motifs and repertoires. Previous studies have detailed the peptide binding specificity of the HLA A2, A3, B7, and B44 supertypes, and predicted, on the basis of MHC pocket structures, known motifs, or the sequence of T cell epitopes, the existence of the HLA A1 and A24 supertypes. Direct experimental validation of the A1 and A24 supertypes, however, has been lacking. In the current study, the peptide-binding repertoires and main anchor specificities of several common HLA A molecules (A*0101, A*2301, A*2402, A*2601, A*2902, and A*3002) predicted to be members of the A1 or A24 supertypes were analyzed and defined using single amino acid substituted peptides and a large peptide library. Based on the present findings, the A1 supertype includes A*0101, A*2601, A*2902, and A*3002, whereas the A24 supertype includes A*2301 and A*2402. Interestingly, A*2902 is associated with a motif and peptide binding repertoire that overlaps significantly with those of all of the A1- and A24-supertype molecules studied, representing-to our knowledge-the first report of significant cross-reactivity among molecules belonging to different supertypes.

Amino Acid Motifs↗
PubMed2003

Lipomas of the oral cavity: clinical findings, histological classification and proliferative activity of 46 cases.

Lipomas represent about 1 to 5% of all neoplasms of the oral cavity. Although relatively common, few large series of intraoral lipomas and its variants are seen in the literature. Therefore, the authors present the clinical, histological and immunohistochemical features of 46 cases of intraoral lipomas reviewed from the files of the University of Campinas Dental School from 1970 to 2001. Most of the cases affected adults, without gender predilection, and the main involved sites were the buccal mucosa (21 cases), tongue (six cases), lips (six cases) and floor of mouth (five cases). The histological analysis revealed 21 cases of lipoma, 18 fibrolipomas, four intramuscular lipomas, two minor salivary gland lipomas and one spindle cell lipoma. PCNA and ki-67 expression indexes were higher in spindle cell lipoma, intramuscular lipomas and fibrolipomas compared to common lipomas, but the differences were not statistically significant. All lesions were removed surgically and none showed recurrence, regardless of the various proliferative activities.

Adolescent↗
PubMed1991

[Thymus hyperplasia: classification, problems of patho- and morphogenesis, importance in human pathology].

Thymus hyperplasia may be congenital (thymomegaly) and acquired (acquired thymomegaly, "tumour-like" hyperplasia, lymphofollicular hyperplasia). Congenital thymomegaly is represented by variants with hypo- and hyperfunction of an adequately formed thymus and results from the congenital neuro-endocrine disturbances. Thymomegaly with a thymus hypofunction is a marker of the immunodeficiency. Acquired thymomegaly is also represented by two variants with hypo- and hyper-function of the thymus and is in fact a "phenocopy" of the congenital one. "Tumor-like" thymus hyperplasia is a rare form of its pathology with a thymic weight reaching 800 g thus resulting in a syndrome of the mediastinum organs compression. Lymphofollicular thymus hyperplasia can not be always considered to be a thymus pathology but it is characteristic of autoimmune and infectious-allergic diseases with lymphoid follicles localizing in the hyperplastic intralobular perivascular spaces. Thymus parenchyma changes depend on the main disease and play a main role in the development of thymus dysfunction, for example, in the autoimmune diseases. Formation of lymphoid follicles in the dilated perivascular spaces is a non-specific process.

Diagnosis, Differential↗
PubMedDate not supplied

[Mitotic regimen of histologic variants infiltrating duct carcinoma of the breast].

Mitotic regimen was studied in 197 cases of infiltrating duct mammary carcinoma found at mammography screening and subdivided according to the prognostic F. Linell classification (1980) into two groups (1-tubular, duct-tubular and II-comedo-type carcinoma). Indices of the mitotic regimen and particularly mitotic index showed statistical differences in these groups. Comedo-type carcinoma with a poorest prognosis is characterized by a high mitotic index (near 20% and higher) and pronounced mitosis pathology correlated with a degree of cell polymorphism. Mitotic index of a tubular and duct-tubular carcinoma is much lower (as a rule lower than 10%) this reflecting their more favourable prognosis.

Adult↗
PubMed2004

Where and when does pancreatic carcinoma start?

The phenotypic classification of pancreatic neoplasms is based on their cellular lineage. Thus, tumors with a ductal, acinar and endocrine phenotype can be distinguished. Most pancreatic neoplasms show a ductal phenotype and can be classified as ductal adenocarcinomas. Less common tumors with a ductal phenotype are the variants of ductal adenocarcinoma, intraductal papillary-mucinous neoplasm (including colloid carcinoma), mucinous cystic neoplasm, medullary carcinoma and other rare tumors. Ductal adenocarcinomas most likely develop on the basis of ductal proliferative lesions arising in the pancreatic duct system. A recently adopted classification system for these lesions distinguishes between three grades of pancreatic intraepithelial neoplasia (PanIN). Molecular studies revealed that PanIN-2 and PanIN-3 lesions represent a distinct step toward invasive carcinoma.

Carcinoma in Situ↗
PubMed1976

Ultrastructural classification of pituitary adenomas.

Forty-eight surgically removed pituitary adenomas have been investigated by electron microscopy. Distinct differences in fine structural appearances permitted their separation into 5 classes: 1) Growth hormone, (GH)-cell tumors; 2) Prolactin cell tumors; 3) Mixed adenomas composed of GH and prolactin cells; 4) Adrenocorticotrophic-Melanocyte stimulating hormone (ACTH-MSH) cell tumors; 5) Undifferentiated cell adenomas. Densely and sparsely granulated tumors were distinguished within classes 1, 2 and 4. Although these two forms appeared to represent well defined entities, they may be variants of the same tumor differing only in pace of hormone production and/or release. Number and size of secretory granules varied considerably among tumors composed of the same cell type indicating that pituitary tumor classification cannot be based solely on granule morphology. This classification takes into account morphogenesis with emphasis on clinical features and structure-function relationship.

Adenoma, Acidophil↗
PubMed1999

Hürthle cell carcinoma: A malignancy of low-grade potential.

BACKGROUND: Hürthle cell carcinoma of the thyroid is a variant of follicular carcinoma, which has been considered by many as a more aggressive disease than the usual well-differentiated carcinoma of the thyroid. Others, however, have found Hürthle cell carcinoma to be a low-grade malignancy with little morbidity or mortality. METHODS: This is a retrospective report on all patients with Hürthle cell carcinoma diagnosed during the years 1951-1997 by the authors. The behavior of the disease and results of treatment were analyzed biostatistically and the outcome was compared with that of patients with pure follicular carcinoma treated during the same period. RESULTS: Forty-two patients were diagnosed with Hürthle cell carcinoma and 153 with follicular carcinoma during this period (2.8% and 10.3% of all differentiated carcinomas of the thyroid, respectively). The rate of local recurrence and disease-related mortality were both 9.5%, compared with 3.2% & 15.7%, respectively, for the follicular cancers. There was a trend for better outcome in patients younger than 55 years of age, in patients with tumors under 4 cm in size, and in patients treated by total thyroidectomy. Distant metastases occurred in four patients (9.5%) and were the cause of disease-related mortality in three. CONCLUSIONS: When treated assertively, Hürthle cell carcinoma of the thyroid, an oncocytic variant of follicular carcinoma, has a favorable outcome, similar to that of pure follicular carcinoma. Uniting those two entities in a future classification and reporting should be considered.

Adenocarcinoma↗
PubMed1988

Histopathologic classification of small cell lung cancer. Changing concepts and terminology.

Considerable attention has been devoted to the diagnosis of small cell lung carcinoma (SCLC) and its subtypes. In the literature contradictory opinions have been published concerning the clinical implications of subtyping, largely because of the different criteria used by different pathologists. This article is a consensus report by the Pathology Committee of the International Association for the Study of Lung Cancer. The following classification of SCLC is recommended: (1) Small cell carcinoma. This subtype includes most of the tumors previously included in the oat cell and intermediate subtypes. More than 90% of untreated SCLC fall into this category. (2) Mixed small cell/large cell carcinoma. This subtype, which may be associated with a poor prognosis and response to therapy, contains a spectrum of cell types ranging from typical SCLC to larger cells having prominent nucleoli and resembling large cell carcinoma. (3) Combined small cell carcinomas. Typical SCLC elements are intimately admixed with areas of differentiated squamous cell or adenocarcinoma. This simplified classification of SCLC will facilitate uniformity in the diagnosis and further our understanding of the clinical significance of the rarer SCLC with variant morphologies.

Carcinoma, Small Cell↗
PubMed1982

Immunodeficiency and syndromes: a nosographic approach.

Immunodeficiency disorders can be classified on clinical grounds into two broad groups according to whether all features are the result of the immune defect (immunodeficiency syndromes) or whether many, even prominent, features cannot be explained by the immune defect (syndromes with immunodeficiency). X-linked agammaglobulinemia and X-linked chronic granulomatous disease are paradigmatic examples of immunodeficiency syndromes. Despite some overlap (for instance extra-immune symptoms, although minor, are present in several variants of severe combined immunodeficiency and chronic granulomatous disease) immunodeficiency syndromes and syndromes with immunodeficiency are easily distinguishable. Together with the pathogenetic classification of the WHO, the present approach to a clinical classification amplifies the operational concept of immunodeficiency also from a therapeutic point of view.

Acrodermatitis↗
PubMed2002

Histological features of hypovascular or avascular renal cell carcinoma: the experience at four university hospitals.

BACKGROUND: We aimed to evaluate the pathological features of hypovascular or avascular renal cell carcinoma (RCC), by the retrospective review of the histological features that coincide with hypovascular or avascular RCC. METHODS: Seven hundred and ninety-one patients who underwent both preoperative angiography and nephrectomy were examined. Of these patients, the 126 patients (15.9%) who showed hypovascular or avascular angiographic features were selected. Patients with hemorrhage or cyst(s), or with at least 50% necrosis or more in the tumor, and those with renal tumor metastatic to the kidney were excluded. The criteria proposed by the World Health Organization (1998) were adopted for the histological classification. RESULTS: Papillary RCC was the most frequently observed hypovascular or avascular renal tumor (44 cases; 34.9%). The vascularity differed among the variants, i.e., some cases had a basophilic and solid variant with avascular features, while the remaining cases had wide stromal organization showing hypovascular features. The second most frequently observed hyporascular or avascular RCC was chromophobe cell carcinoma (35 cases; 27.8%). No difference in vascularity was detected between variants, except for 2 cases with sarcomatoid changes (avascular features). The third most frequently observed hypovascular or avascular RCC was cyst-associated RCC (29 cases; 23%). All of the 7 RCCs originating in a cyst showed avascular features, and the remaining 22 cystic RCCs showed hypovascular features. The remaining hypovascular or avascular RCCs were cases of clear cell carcinoma accompanied by sarcomatoid changes (8 cases; 6.3%), spindle cell carcinoma (5 cases; 4.0%), and collecting-duct carcinoma (5 cases; 4.0%). CONCLUSION: Hypovascular or avascular RCC can be categorized as non-clear cell carcinoma and some clear cell carcinoma accompanied by sarcomatoid changes.

Carcinoma, Renal Cell↗