1,720,973 research outputs found
Adenoid (acantholytic) squamous cell carcinoma of the skin.
No full textCutaneous adenoid squamous carcinoma (ASCC) is a distinctive neoplasm featuring tumor cell acantholysis. Because this lesion occasionally may prove troublesome diagnostically, we studied the clinical, histologic, and immunohistochemical features of 55 examples in order to further elucidate its characteristics. ASCC most often occurred in the skin of the head and neck in elderly patients. Of 49 patients in this series, 46 were men and 3 were women; their ages at diagnosis ranged from 25 to 90 yr, with a mean of 71. Six individuals had 2 metachronous neoplasms. ASCC generally behaved in an indolent manner, although 19\% of cases did metastasize widely and prove fatal. Tumor size of greater than 1.5 cm appeared to correlate with the risk of an adverse clinical outcome. In addition, 10 patients with ASCC of the skin subsequently developed visceral malignancies. The cutaneous neoplasms were typified by invasive, tubular or pseudoglandular profiles of polygonal cells in the dermis, with glassy eosinophilic cytoplasm and focal squamous pearl formation. Connections to the overlying epidermis were commonly apparent. Immunohistochemically, ASCC demonstrated uniform reactivity for cytokeratin, but lacked markers of specialized glandular cells. These findings militate against the interpretation that such tumors demonstrate partial adnexal differentiation, and show that immunohistology may prove helpful in the differential diagnosis between ASCC and primary or metastatic adenocarcinomas of the skin
MALIGNANT TUMOURS IN THE ARAGONESE SERIES OF SAINT DOMENICO MAGGIORE OF NAPLES (15th- 16th CENTURIES)
Full text linkCancer nowadays represents the second cause of death in advanced countries. However, there are only five cases of malignant soft tissue tumors in the paleopathological literature.1 The rarity of cancer in Antiquity is a highly debated problem and the main reasons are apparently the short life span of past populations, the scarcity of mummified remains and the technical difficulties for detecting neoplastic lesions in mummified tissues.
Three ancient malignant tumors were identified in the Renaissance mummies of the Aragonese court (15th-16th centuries), that are preserved in the Basilica of Saint Domenico Maggiore in Naples.
The autopsy performed on the natural mummy of Ferrante I of Aragon (1424-1494), revealed a well-preserved rectum. Histology showed crowded epithelial tumour cells, disposed in cords and glands, typical of a moderately differentiated mucinous adenocarcinoma. Strong immunoreactivity for pan-cytokeratin was shown and DNA analysis of K-RAS exons 1-2 demonstrated the presence of a mutation characteristic of sporadic colorectal cancer and associated with exposure to natural carcinogens present in the diet.
The histological study of the natural mummy of Prince Luigi Carafa (1511-1576) revealed an extraordinarily well-preserved colon mucosa with an evident villous adenoma and strong immune-positivity for keratins and p53. In some points, clear invasion of the polyp stalk or of the submucosa was evident: this histological picture is that of a well differentiated adenocarcinoma at stage T1.
The natural mummy of Duke Ferdinando Orsini (ca1490-1549), showed a wide destructive lesion of the right orbit and nose. Bone histology revealed large lacunae destroying the normal lamellar bone, containing clusters of cells with solid epithelial-like aspects and a darker margin “at palisade” (Fig. c, arrow), with strong positivity for pan-cytokeratin, typical of a destructive basal cell carcinoma.
The small series of mummies from Naples, composed of eleven adults (10 males and 1 female) with well three cases of cancer in individuals between 55 and 71 years of age, is very important. Despite the limited number of specimens, the cancer prevalence of 27.0% that was found is similar to the 30.9% rate in modern countries. We can hypothesize that cancer must have been frequent after 50-60 years of age, at least in the Renaissance elite classes with peculiar alimentary and life style habits, as in this series of Spanish nobles.
In conclusion, the statements according to which cancer was an extremely rare event in the past populations should be revised. Future accurate autoptic studies of mummies will be essential not only to diagnose new paleopathological cases, but also to clarify the mechanisms of ancient neoplastic progression
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Hemangiopericytoma: histopathological pattern or clinicopathologic entity?
No full textThe tumor designated by Stout and Murray as "hemangiopericytoma" (HPC) more than 50 years ago continues to represent a source of uncertainty and disagreement among pathologists. In particular, questions exist regarding the synonymity of a hemangiopericytomatous growth pattern--defined by a monomorphic population of compact polygonal or bluntly fusiform cells and a branching stromal vascular pattern with a "staghorn" configuration--and the presence of a reproducible biological entity. It has been shown repeatedly that these same histologic features may be observed at least focally in a diversity of neoplasms, including "true" hemangiopericytomas, synovial sarcomas, mesenchymal chondrosarcomas, infantile fibrosarcomas, malignant fibrous histiocytomas, malignant peripheral nerve sheath tumors, leiomyosarcomas, endometrial stromal sarcomas, solitary fibrous tumors, myofibromas, malignant mesotheliomas, thymomas, sarcomatoid carcinomas, malignant melanomas, and "phosphaturic mesenchymal tumors." Despite their potential sharing of the microscopic attributes in question, such neoplasms have individualistic clinical features and can also be distinguished from one another by specialized pathologic analyses. HPC is "defined" in that context by reactivity for vimentin, with or without CD34 and CD57, but it lacks other immunodeterminants of epithelial, neural, and myogenous differentiation. Paradoxically, this phenotype is indeed associated with the presence of myogenous-type cytoplasmic filaments in ultrastructural evaluations of HPC. Other lesions that may resemble "true" HPC--but which possess dissimilar subcellular and clinical characteristics--include solitary fibrous tumors, hemangiopericytomalike tumors of the sinonasal tract, and "infantile (congenital) hemangiopericytomas." Such observations suggest that the hemangiopericytoma is both a pathologic entity and a morphological pattern, and they emphasize the utility of adjuvant pathologic studies in this diagnostic context
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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