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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↗

Medulloblastoma: present concepts of stratification into risk groups.

For the past two decades, staging studies have been used to stratify children with medulloblastoma into risk groups. Therapeutic approaches have been based on separation of patients into 'average-risk' and 'poor-risk' categories. The extent of disease at diagnosis has been most reproducibly shown to be of prognostic significance, but age at diagnosis and amount of residual disease after surgery or extent of resection have also been commonly incorporated into stratification schemata. Tumor histology has been variably related to outcome. Biologic markers, especially molecular genetic findings, have not yet been incorporated into risk classifications, but will likely add to the understanding of medulloblastoma and may significantly alter concepts of staging and treatment.

Cerebellar Neoplasms↗

Molecular profiling of breast cancer: portraits but not physiognomy.

Breast cancers differ in response to treatment and may have a divergent clinical course despite having a similar histopathological appearance. New technology using DNA microarrays provides a systematic method to identify key markers for prognosis and treatment response by profiling thousands of genes expressed in a single cancer. Microarray profiling of 38 invasive breast cancers now confirms striking molecular differences between ductal carcinoma specimens and suggests a new classification for oestrogen-receptor negative breast cancer. Future approaches will need to include methods for high-throughput clinical validation and the ability to analyze microscopic samples.

Breast Neoplasms↗

Mastocytosis: the great masquerader.

Variants of mastocytosis can present with puzzling cutaneous and systemic symptoms and signs that can result in an erroneous diagnosis of idiopathic urticaria or idiopathic anayphylaxis. The molecular basis of mastocytosis is now better understood, with updated classification based on distinct growth factor and oncogene abnormalities. Elicitation of a full history and careful attention to the skin examination will usually provide the clinician enough information to deduce that the condition is not simply chronic idiopathic urticaria.

Adult↗

The 41st Annual Meeting of the American Society of Clinical Oncology. Orlando, FL, USA, 13-17 May, 2005.

Nearly 29,000 scientists from all over the world gathered at the 41st Annual Meeting of the American Society of Clinical Oncology (ASCO). The programme included the presentation of new data encompassing all the fields of cancer research, including cancer prevention, treatment and biology. Special sessions were added to summarise and discuss achievements in the field of translational research on biologically targeted therapies. Rational drug design based on tumour biology and genetics represents a promising strategy to overcome the limitations of conventional chemotherapy. Increased knowledge in the field of molecular oncology, genetics and progress in technology are revolutionising tumour classification, prognostication, prediction and therapy. However, at present, for most of the diseases, improvements brought about by the newer therapies are small, although clinically meaningful. This review will briefly address some of the most interesting data presented at ASCO 2005.

Humans↗

Wallinia chavarriae n. sp. (Trematoda: Macroderoididae) in Astyanax aeneus (Gunther, 1860) and Bryconamericus scleroparius (Regan, 1908) (Osteichthyes: Characidae) from the Area de Conservación Guanacaste, Costa Rica.

Wallinia chavarriae n. sp. is described from the small-bodied characids Astyanax aeneus and Bryconamericus scleroparius in the Area de Conservación Guanacaste, northwestern Costa Rica. The species differs from W. valenciae in possessing an acetabulum that is smaller than the oral sucker and vitelline follicles that are ovoid or rounded rather than elongate and tubular. Detailed comparison between these 2 species is handicapped by the less than satisfactory condition of the type and only museum specimen of W. valenciae. Wallinia chavarriae and W. valenciae belong to a subfamily of trematodes, Walliniinae, that arguably includes Creptotrematina spp., Magnivitellum simplex, and possibly Margotrema. The morphology of walliniines suggests that they are macroderoidids, but a clearer understanding of their classification could be gained from their larval morphology or from molecular systematic studies. The host associations of a monophyletic Walliniinae would indicate diversification within 2 groups of freshwater fishes: the neotropical characids for species of Wallinia, Creptotrematina, and Magnivitellum and the endemic central Mexican goodeids for those of Margotrema. The biogeography and host associations of these parasites provide a system for studies of potential host switching and vicariance, involving the middle-American and neotropical regions.

Animals↗

von Willebrand factor: biological function and molecular defects.

The human von Willebrand factor (vWF) plays a pivotal role in the mechanisms of blood clotting and platelet thrombus formation; it also binds and stabilizes factor VIII procoagulant protein. The biological functions of vWF are dependent on distinct molecular domains responsible for the specificity and affinity for ligands. The multimeric structure of vWF provides an array of binding sites that allow multivalent interactions, thus supporting the formation of stable platelet aggregates at the site of vascular injury, particularly under flow conditions characterized by high shear stress. Quantitative and qualitative abnormalities of vWF cause the most common congenital bleeding disorder in humans, the von Willebrand disease (vWD). This review will provide an update on the recent advances toward the elucidation of structure-function relationships and the detection of molecular defects leading to vWD and will highlight the revised classification of vWD.

Heparin↗

Fine-needle aspiration biopsy of lymphoproliferative disorders--interpretations based on morphologic criteria alone: results from the College of American Pathologists Interlaboratory Comparison Program in Nongynecologic Cytopathology.

CONTEXT: Diagnosis of lymphoproliferative disorders is one of the most challenging tasks faced by the cytologist. The initial cytomorphologic evaluation of lymphoproliferative lesions directs the choice of ancillary studies that ultimately lead to a diagnosis based on the World Health Organization classification system using a composite of clinical, morphologic, immunophenotypic, and molecular features. OBJECTIVE: To evaluate the ability of participating laboratories in the College of American Pathologists Interlaboratory Comparison Program in Non-Gynecologic Cytopathology to appropriately categorize lymphoproliferative lesions based solely on cytomorphologic criteria. DESIGN: Laboratory responses for lymph node aspirates were examined. All responses were based on review of glass slides without ancillary immunologic or molecular data available. The benchmarking data provided for each specific diagnosis were analyzed, with a focus on the performance for evaluation of lymphoproliferative lesions. RESULTS: Based on morphology alone, responses for lymph node aspirates in the Non-Gynecologic Cytopathology program were correct to the exact reference diagnosis for 87.1% of Hodgkin lymphoma. Non-Hodgkin lymphoma was identified in 69.5% of the large cell non-Hodgkin lymphoma cases, of which 66.8% were correctly classified as large cell type. Non-Hodgkin lymphoma was identified in 68.1% of non-Hodgkin lymphoma, other than large cell cases, and of these, 94.7% were identified as other than large cell type. CONCLUSIONS: The spectrum of specific responses was consistent for lymphoproliferative lesions, with a reasonable differential diagnosis based on cytomorphology alone, which, in practice, facilitates the appropriate choice of immunophenotypic markers and other ancillary studies.

Biopsy, Fine-Needle↗

[Pneumocystis carinii is still a dangerous opportunist. The infection is continuously a threat to immunocompromised patients].

Despite recent decrease in the incidence of Pneumocystis carinii pneumonia (PCP) among patients infected with HIV (human immunodeficiency virus), PCP remains a threat to other categories of immunocompromised patients. The article provides an outline of recent, mainly molecular genetic, findings in P. carinii research, including its new classification as a primitive fungus, host specificity and verified de novo infection in HIV-infected subjects. As the pathogen still defies propagation in vitro, laboratory diagnosis is dependent on microscopic demonstration of the organism. Diagnostic specificity can be enhanced by generating specific PCR (polymerase chain reaction) products which can be sequenced for genotyping. Findings in animal studies and epidemiological observations (e.g., in outbreaks of PCP among immunocompromised hospital patients), suggest transmission of PCP infection to be airborne. Genetic methods have been used to study the mode of P. carinii transmission. Nucleic acids of the human form of P. carinii (P. carinii f. sp. hominis) have been detected in the air of hospital wards, indicating susceptible patients to be at risk. By contrast, findings obtained with the same methods in studies of person-to-person transmission of P. carinii among clustered cases of PCP in hospitals suggest infection to be environmentally acquired. Thus, many questions remain to be answered regarding the occurrence and transmission of P. carinii infection.

AIDS-Related Opportunistic Infections↗

Modulation of cellular signaling pathways: prospects for targeted therapy in hematological malignancies.

The high remission rates observed in patients with chronic myelogenous leukemia who receive Imatinib mesylate (Gleevec) indicate that targeted therapy for hematological malignancies is achievable. At the same time, progress in cellular biology over the past decade has resulted in a better understanding of the process of malignant transformation, a better classification of subtypes of each disease on the basis of molecular markers, and a better characterization of the molecular targets for drug development. These advances have already spawned the development of such effective agents as monoclonal antibodies and specific enzyme inhibitors. This review attempts to provide a practical introduction to the complex and growing field of targeted therapy in hematological malignancies.

Antineoplastic Agents↗

Gene expression in kidney cancer is associated with cytogenetic abnormalities, metastasis formation, and patient survival.

Current diagnosis of renal cancer consists of histopathologic examination of tissue sections and classification into tumor stages and grades of malignancy. Until recently, molecular differences between tumor types were largely unknown. To examine such differences, we did gene expression measurements of 112 renal cell carcinoma and normal kidney samples on renal cell carcinoma-specific cDNA microarrays containing 4,207 genes and expressed sequence tags. The gene expression patterns showed deregulation of complete biological pathways in the tumors. Many of the molecular changes corresponded well to the histopathologic tumor types, and a set of 80 genes was sufficient to classify tumors with a very low error rate. Distinct gene expression signatures were associated with chromosomal abnormalities of tumor cells, metastasis formation, and patient survival. The data highlight the benefit of microarrays to detect novel tumor classes and to identify genes that are associated with patient variables and tumor properties.

Adult↗

[A man with oral ulcers caused by hypereosinophilic syndrome and a good response to the tyrosine-kinase inhibitor imatinib].

For the last 2 years, a 55-year-old man had painful, recurrent oral ulcers. Histological examination showed non-specific inflammation. Eosinophilia in the blood and bone marrow raised the suspicion of hypereosinophilic syndrome. No other specific organ involvement was observed. The diagnosis was confirmed by detection of the fusion gene 'FIP1-like-1-platelet-derived growth factor receptor alpha' (FIP1L1-PDGFRA) in the peripheral blood and bone marrow. Treatment with the tyrosine-kinase inhibitor imatinib resulted in a rapid response that has been maintained for more than 2 years. Hypereosinophilic syndrome is a rare haematological disorder. Until recently diagnosis was made by exclusion, and the course of disease was often fatal. Fusion of the FIP1L1 gene to the PDGFRA gene was identified recently in some patients with hypereosinophilic syndrome. The fusion results in a novel tyrosine kinase that is constitutively activated and may induce proliferation ofhaematopoietic cells. Treatment with imatinib targets this tyrosine kinase. These advances in our understanding of the molecular biology of the disease will lead to a new classification of hypereosinophilic syndrome with specific therapeutic options.

Benzamides↗

[Antenatal forms of osteogenesis imperfecta. Classification trial].

A classification of the different types of osteogenesis imperfecta is proposed. There are 3 main groups: the lethal type, the severe type and the so-called regressive type, with a more favorable course. This classification was established to allow for a more precise definition of the prognosis at the time of birth, or even in utero when diagnosis is made by ultrasonography. It should also allow for better classification of the data obtained by the study of the molecular collagen. This project is different from Sillence's one by the exclusion of type II B lethal types, which are often compatible with survival. In view of the frequent occurrence of a dominant mutation in the type II A, the more generally accepted recessive transmission is discussed.

Diagnosis, Differential↗

From bedside to bench and back. The diagnosis and biology of bullous diseases.

The history of dermatology is replete with examples where astute physicians have made key observations that have led to the recognition of distinct diseases and syndromes. While clinicians may be either lumpers or splitters, their unifying theme has been that of identifying common elements among patients to assist in their diagnosis, classification, and treatment. Light microscopy, electron microscopy, immunopathologic techniques, and molecular biology have provided dermatologists additional data to assist in their analysis of incompletely understood and poorly classified skin diseases. Application of these techniques over the past 40 years to patients with bullous diseases has led to the development of many new concepts including the following: (1) patients with bullous diseases have autoantibodies that target disease-specific antigens that represent important structural components of normal human skin; (2) autoantibodies from patients with certain bullous diseases are pathogenic in experimental animal models; and (3) some of the same structural proteins targeted by autoantibodies in patients with acquired autoimmune bullous diseases are mutated in patients with inherited bullous diseases. An overview of these concepts is the subject of this brief review.

Animals↗

[Clinical aspects and follow-up in dilated cardiomyopathy].

Dilative cardiomyopathy is a heterogeneous myocardial disease characterized by a depressed contractile function and ventricular dilation. The exercise intolerance of patients with dilative cardiomyopathy is partly explained by changes of metabolism and composition of skeletal muscle, whereas the physical findings result from progressive heart failure and cardiac remodeling. The clinical course of the disease is highly variable and prognostic indicators of progressive heart failure or cardiac arrhythmias are of little value in the assessment of cardiac risk in an individual patient. During recent years the mortality of patients with dilative cardiomyopathy was 5-15%, which appears to be lower than previously reported. The differences in mortality today and in previous years may be explained by a more precise and earlier diagnosis of the disease and possibly better treatment strategies. Patients with a severely depressed left ventricular function but a stable clinical course, a good hemodynamic response to therapy, and an oxygen uptake of > 12 ml/kg min can be followed without heart transplantation. It can be expected that the definition of the molecular causes of dilative cardiomyopathy will lead to a better classification of the patients and the development of more efficient treatment strategies.

Cardiomyopathy, Dilated↗

Autosomal dominant spinocerebellar ataxia with sensory axonal neuropathy (SCA4): clinical description and genetic localization to chromosome 16q22.1.

The hereditary ataxias represent a clinically and genetically heterogeneous group of neurodegenerative disorders. Various classification schemes based on clinical criteria are being replaced as molecular characterization of the ataxias proceeds; so far, seven distinct autosomal dominant hereditary ataxias have been genetically mapped in the human genome. We report linkage to chromosome 16q22.1 for one of these genes (SCA4) in a five-generation family with an autosomal dominant, late-onset spinocerebellar ataxia; the gene is tightly linked to the microsatellite marker D16S397 (LOD score = 5.93 at theta = .00). In addition, we present clinical and electrophysiological data regarding the distinct and previously unreported phenotype consisting of ataxia with the invariant presence of a prominent axonal sensory neuropathy.

Axons↗

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