Oral leukoplakia is the most common potentially malignant oral lesion. While the clinicopathological features in white patients are well characterised, this is not the case in black people. The aim of this study is to analyse the differences in the clinicopathological features of oral leukoplakia in different racial groups in the greater Johannesburg area of South Africa, with special emphasis on the black population. Only 14% of oral leukoplakia occurred in black persons compared to 80% in white persons. In contrast to white persons, black persons were diagnosed with oral leukoplakia at a younger age; there were more males affected than females; and the proportion of idiopathic leukoplakias was greater. There were significantly more black people (23%) with non-homogenous leukoplakia oral leukoplakia than white people with non-homogenous leukoplakia (13%), but there were significantly more white people (51%) than black people (23%) with dysplastic oral leukoplakia; and while in white people the floor of the mouth was the most frequently affected site, in black people it was the buccal mucosa. This study provides important differences in the clinicopathological features of oral leukoplakia between black persons and white persons.

Thesis (M.S.)--University of Michigan, 1963. / Typescript (photocopy). Includes bibliographical references (leaves 49-51). Also issued in print.

Thesis (M.S.)--University of Michigan, 1963. / Typescript (photocopy). eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 49-51).

Thesis (M.S.)--University of Michigan, 1987.

Thesis (M.S.)--University of Michigan, 1987.

Prolifererande verrukös leukoplaki, PVL, är en ovanlig sjukdom som yttrar sig genom multipla, vita förändringar i munslemhinnan som recidiverar och med tiden riskerar att utvecklas till cancer. Diagnosen kan endast ställas kliniskt när sjukdomsförloppet pågått under lång tid och det finns heller inga effektiva behandlingsmetoder. Etiologin till sjukdomen är okänd, men idag vet man att det finns ett samband mellan cancerutveckling och vissa virustyper.Syftet med studien är att undersöka om det går att påvisa humant papillom virus, HPV, i vävnadsprover från patienter som kan misstänkas ha PVL. Urvalet bestod av 11 patientfall, där vävnadsprover från biobanken vid avdelningen för oral patologi, Malmö högskola, samlats in och studerats med kromogen in situ hybridisering. Resultaten visade en högre förekomst av HPV i biopsier tagna i det senare skedet av sjukdomen jämfört med tidigare biopsier. En specifik HPV-genotyp kunde dock inte identifieras. I denna studie har det inte varit möjligt att påvisa HPV med in situ hybridisering, i ett tidigt staddium av PVL, som en möjlig indikator på sjukdomsutveckling. / Proliferative verrucous leukoplakia, PVL, is a rare disease that is characterized by multiple and recurrent white lesions in the oral epithelium which over time may develop into cancer. The diagnosis can only be made by the clinician when the disease has progressed for a long time. There is no effective treatment. The etiology of the disease is unknown but today it is known that there is a link between cancer and certain viruses.The purpose of this study is to investigate whether it is possible to detect human papilloma virus, HPV, in tissue samples from patients who possibly are affected by PVL.The selected samples consisted of 11 cases in which tissue samples from the biobank at the Department of Oral Pathology at Malmö University, were collected and HPV was detected by chromogenic in situ hybridization. The results showed a higher incidence of HPV in biopsies taken at a later stage of the disease compared with previous biopsies. However, a specific HPV genotype could not be identified.In this study, it has not been possible to demonstrate HPV with in situ hybridization at an early state of PVL as a putative indicator of disease development

Orientador: Marcelo Macedo Crivelini / Resumo: As leucoplasias são lesões orais que podem apresentar vários aspectos clínicos e histológicos e são associadas a malignidade geralmente quando apresentam alterações displásicas. Contudo, essas transformações podem ocorrer em lesões sem displasia que apresentam aspecto clínico inocente. Por esse motivo nossa proposta foi estudar a expressão imuno-histoquímica do p53 e PCNA em leucoplasias sem displasias, buscando correlacionar os resultados apenas com o grau de queratinização epitelial. Para isso foram utilizados as leucoplasias Grau I, II e III de Grinspan, num total de 24 lesões, todas localizadas em mucosa jugal. A maior parte das leucoplasias, em seus diferentes graus de queratinização, apresentou expressão de p53 e PCNA. A marcação do p53 restringiu-se às camadas basal e parabasal, enquanto a do PCNA ocorreu em praticamente todas as camadas epiteliais. O padrão de expressão desses marcadores foi histologicamente e estatisticamente semelhante entre as lesões com esta variação de queratinização. Ficou evidente que os epitélios não displásicos das leucoplasias possuem sinais sub-microscópicos de alterações direcionadas à transformação maligna e o grau de queratinização não se correlacionou ao maior risco desse acontecimento. / Abstract: Leukoplakias are oral lesions that may have many clinical and histologic aspects and they are usually associated with malignancy when dysplastic alterations are shown. However, these transformations may occur in non dysplastic lesions that show harmless clinical aspect. For this reason, our proposal was to study the p53 and PCNA immunohistochemical expression in no dysplastic leukoplakias, trying to correlate the results with the epitelial keratinization degree only. For this, 24 leykoplakias were used, lesions with degree I, II and III of Grinspan, all located in buccal mucosa. Most of the leukoplakias showed p53 and PCNA expression in their different keratinization degrees. The p53 marking were confined at basal and parabasal layer, while the PCNA marking occurred in practically all epithelia layers. The expression pattern of these markers were histologically and estatistically similar between the lesions with this keratinization variation. It was evident that non dysplastic epithelium of leukoplakias have no visible signs of the alterations at the microscope which leads to malignant transformation, and that the keratinization degree did not correlate to greater risk of this event. / Mestre

Orientador: Marcelo Macedo Crivelini / Resumo: Tem sido descrito que cerca de 30% do total leucoplasias possui tendência à malignização, a uma taxa de 2,9% ao ano. O envolvimento concomitante de leucoplasias com Candida albicans tem sido relacionado a possíveis processos de malignidade, tornando este questionamento uma fonte de debate. O presente trabalho avaliou a expressão qualitativa de p 53, Ki-67, PCNA e AgNOR em leucoplasias associadas à Candidose. Não foram observadas diferenças significativamente estatísticas (Tukey test, p<0,05) no grupo corado por AgNOR. Esses resultados discutem a taxa de proliferação celular epitelial e, talvez, indícios de alterações genéticas malignas presentes nas leucoplasias associadas à Candidose. / Abstract: It has been described that 30% of leukoplakia with tendences to malignization, in a rate of 2,9% per year. The envolvement of leukoplakia associated to Candida albicans has been related to possible process of malignity, witch makes this question a source of debate. The aim of this study was to evaluate the qualitative expression of p53, Ki-67, PCNA and AgNOR in leukoplakia related to Candidosis. It wasþt observated statistical diferences in the AgNOR group (F test, p<0,05-ANOVA one-way). This results discuss a rate of celular epitelial proliferation and possibly genetic alterations present in leukoplakia related to Candidosis. / Mestre

Made available in DSpace on 2017-03-14T14:10:04Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-08-06. Added 1 bitstream(s) on 2017-03-14T14:42:46Z : No. of bitstreams: 1 000874686_20170806.pdf: 140937 bytes, checksum: e05eb81c98529a6d9585ef5947e33e5f (MD5) Bitstreams deleted on 2017-08-07T14:09:17Z: 000874686_20170806.pdf,. Added 1 bitstream(s) on 2017-08-07T14:10:21Z : No. of bitstreams: 1 000874686.pdf: 842380 bytes, checksum: 1fee33ddb0a32a78cc9d3d8bf6b6f0cf (MD5) / O carcinoma espinocelular (CEC) representa mais de 95% de todas as neoplasias malignas que acometem a cavidade oral e muitas vezes estes tumores são precedidos por alterações clínicas que apresentam um evidente potencial de transformação maligna, as quais são chamadas de desordens potencialmente malignas orais (DPMO). Dentre estas, a leucoplasia oral (LO) é a principal condição dentre as DPMOs com uma taxa de incidência igual a 3,4% e uma taxa de transformação maligna que varia de 0,2% até 17,5%. Uma forma menos reconhecida e ainda pouco compreendida de LO denominada leucoplasia verrucosa proliferativa (LVP), representa uma variante de comportamento persistente e progressivo para malignidade, com uma taxa de transformação maligna ocorrendo em mais de 70% dos casos. O diagnóstico da LVP atualmente só é possível através da observação temporal e individual de cada paciente, com a demonstração de progressão clínica e histológica das lesões para um CEC. A dificuldade no diagnóstico precoce da LVP decorre da sobreposição de características clínicas e histopatológicas, especialmente em casos de LO multifocal convencional. Portanto, foi proposto inicialmente realizar a classificação de casos multifocais de LO encontrados no Serviço de Medicina Bucal da Faculdade de Odontologia de Araraquara - UNESP, durante os anos de 1995 até 2015, segundo descrição da Organização Mundial da Saúde (OMS, 2005) e critérios diagnósticos para LVP atualmente propostos por Cerero-Lapiedra (2010) e Carrard (2013). Posteriormente, foi realizada uma análise comparativa entre as características clínicas e microscópicas de casos de LVP e LO. Os resultados deste estudo revelaram que dentre 86 casos de LO, 45 casos apresentaram o envolvimento de dois ou mais sítios orais configurando estes como casos de LO multifocal. Segundo avaliação realizada por dois observadores experientes...(Resumo completo, clicar acesso eletrônico abaixo) / The squamous cell carcinoma (SCC) represent more than 95% of all the malignant neoplasia of the oral cavity and most of times these tumors are preceded by clinical conditions that have a potential for malignant transformation called oral potentially malignant disorders (OPMD). Among these, the oral leukoplakia (OL) is the most important OPMD, with an incidence rate of 3.4% and a malignant transformation from 0.2 to 17.5%. A form less recognized and poorly understood of leukoplakia is the proliferative verrucous leukoplakia (PVL) which represents a variant with a persistent and progressive to malignancy behavior, with a malignant transformation ratio up to 70% of cases. Currently, the diagnosis of PVL is only made by the temporal and individual observation of each patient, with the demonstration of clinical and histopathological progression to an SCC. The difficult to stablish an early diagnosis of PVL comes from the overlap of clinical and histopathological features with conventional multifocal OL cases. Therefore, was initially proposed to perform a classification of multifocal OL cases found in the Oral Medicine Service from the Araraquara Dental School - UNESP, between 1995 and 2015, according to the WHO definition (WHO, 2005) and the current suggested diagnostic criteria for PVL by Cerero-Lapiedra (2010) and Carrard (2013). Lately, a comparative analysis was conducted between the clinical and microscopic features from cases of PVL and OL. The results of this study revealed that between 86 cases of OL, 45 presented involvement of two or more setting this as multifocal OL cases. According to the evaluation by two experts, 14/45 were considered true cases of PVL. The classification of the same 45 cases by the WHO definition revealed 21/45 cases as PVL, by the Cerero-Lapiedra 27/45 cases were PVL and 4/45 cases were PVL according to Carrard. Sensitivity, specificity...(Complete abstract eletronic access below)

Betel quid¡]BQ¡^chewing is recognized as a major risk factor for oral precancerous lesions¡]OPLs¡^in Taiwan. The compositions of Betel quid could cause DNA damage. X-ray repair cross complementing Group 1¡]XRCC1¡^plays a crucial role in the process of DNA repair. Polymorphisms in XRCC1 gene may affect DNA repairing ability and modulate the susceptibility of OPLs. The aim of this study was to investigate the association of XRCC1 genetic variants with the risk of BQ-related oral precancerous lesions, including oral leukoplakia¡]OL¡^ and oral submucous fibrosis ( OSF ). A total of 449 males¡]169 OL cases, 82 OSF cases, and 208 healthy controls¡^who habitually chewed BQ were recruited. The genotypes were determined by PCR-RFLP and TaqMan real-time assays. The C allele and T/C+C/C genotypes at XRCC1 -77 were associated with the reduced risk of OL ( AOR=0.54, 95%CI:0.34-0.85 and AOR=0.47, 95%CI:0.28-0.78, respectively ). The 399Gln allele and 399 Arg/Gln+Gln/Gln genotypes were associated with the increased risk of OL¡]AOR=1.94; 95%CI: 1.41-2.67 and AOR=2.64; 95%CI: 1.73-4.03, respectively¡^and OSF ( AOR=1.67; 95%CI: 1.11-2.49 and AOR=2.30; 95%CI: 1.35-3.91, respectively ). The haplotypes or diplotypes contain fewer risk alleles¡]-77T or 399Gln¡^ were with lower risk of OL¡]both Ptrend<0.001¡^and OSF (Ptrend=0.056 and Ptrend=0.040, respectively). In conclusion, our results suggest that polymorphisms of XRCC1 at -77 and 399 may be associated with the risk of OPLs.