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An adaptive knowledge-based model for detecting masses in screening mammogramsBovis, Keir Jonathan January 2003 (has links)
No description available.
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Caracterização das lesões impalpáveis (lesões III E IV), e das alterações em TP53 (p53) na detecção precoce do câncer de mama / Characterization of impalpable lesions (III and IV lesions), and alterations in TP53 in the early detection of breast cancerVivian Rabello Areias 07 April 2011 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / As lesões impalpáveis da mama que muitas das vezes são assintomáticas, podem corresponder à um estágio de progressão de câncer difícil de ser detectado, durante os exames de rotina de palpação da mulher. O único método possível para a descoberta dessas lesões é através dos exames de imagem da mama, de modo geral, através da mamografia, que geralmente ocorre após os 45 anos. Devido a esses fatores, lesões impalpáveis, são frequentemente, descobertas apenas quando o estágio de desenvolvimento da doença já está avançado e as intervenções terapêuticas são menos reparadoras. Com a finalidade de iniciar a caracterização de tumores impalpáveis iniciais, objetivamos analisar o perfil genético (mutação) e epigenético (metilação de região promotora) de regiões do DNA relacionadas ao
gene supressor tumoral TP53, provenientes de biópsias de mulheres residentes do Estado do Rio de Janeiro. Neste trabalho, foram investigadas 34 amostras de tecido de tumor de mama, por sequenciamento de DNA, nos exons de 5 a 8 do gene TP53. Nesta região, não foi encontrada nenhuma mutação. Este resultado pode estar relacionado ao tipo inicial de lesão, de acordo com os dados radiológicos das lesões de categorias 3 e 4 da escala BIRADS. Para verificar o estado de metilação da região promotora do gene TP53, analisamos 30 pares de amostras (sangue e tumor) de pacientes com suspeita de câncer de mama, pela técnica MSP-PCR. Nenhuma amostra tumoral apresentou alteração no estado de metilação na região promotora do gene TP53, quando comparada à amostra normal. Um motivo possível para a
disparidade de resultados em relação à outros trabalhos pode ter sido a utilização da técnica. A caracterização das lesões impalpáveis apenas foi iniciada neste trabalho, no qual pudemos constatar que a mutação em TP53 pode ser um evento mais tardio. Portanto, a lesão mamária, em suas diferentes formas, continuará a ser o assunto investigado por nosso grupo, ampliando o número de amostras e alcançando melhor conexão da conduta e dos métodos clínicos já existentes, com as novas possibilidades de diagnóstico via marcadores moleculares em tumores e fluidos biológicos / Nonpalpable breast lesions that are often asymptomatic, may correspond to a stage of progression of the cancer that is difficult to be detected during routine screening. The only
possible way for their discovery is through breast images preventive examinations, generally mammography, which usually occurs after age 45. Because of these factors, impalpable lesions are often discovered when the developmental stage of the disease is already advanced and therapeutic interventions are less aggressive.This study aimed to characterize impalpable tumors by the analysis of genetic (mutation and instability) and epigenetic (methylation of the promoter region) of DNA regions related to TP53 tumor suppressor gene from impalpable lesions extracted from biopsies of women living in the state of Rio de Janeiro. Were investigated 34 tissue samples from breast cancer by DNA sequencing in exons 5-8 of TP53.
In this region, no mutation was found, this result may be related to the initial type of injury according to data of the radiological lesions of categories 3 and 4 of scale BIRADS . In order to check the status of methylation of the promoter region of the TP53 gene, we analyzed 30 pairs from samples (blood and tumor) of patients with suspected breast cancer, by MSPPCR technique. No tumor sample showed a change in the state of methylation in the promoter region of TP53 as compared to the normal sample. One possible reason for the disparity in the results between this study and the other studies may be related with the applied techniques.
The characterization of the nonpalpable lesions just started this work in which we could verify that the mutation in TP53 may be a later event. Therefore, the breast lesion, in its different forms, remains the subject investigated by this group. We have been worked for expanding the number of samples, so as to link the new possibilities of molecular diagnostics in clinical practice in tumors and biological fluids
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Caracterização das lesões impalpáveis (lesões III E IV), e das alterações em TP53 (p53) na detecção precoce do câncer de mama / Characterization of impalpable lesions (III and IV lesions), and alterations in TP53 in the early detection of breast cancerVivian Rabello Areias 07 April 2011 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / As lesões impalpáveis da mama que muitas das vezes são assintomáticas, podem corresponder à um estágio de progressão de câncer difícil de ser detectado, durante os exames de rotina de palpação da mulher. O único método possível para a descoberta dessas lesões é através dos exames de imagem da mama, de modo geral, através da mamografia, que geralmente ocorre após os 45 anos. Devido a esses fatores, lesões impalpáveis, são frequentemente, descobertas apenas quando o estágio de desenvolvimento da doença já está avançado e as intervenções terapêuticas são menos reparadoras. Com a finalidade de iniciar a caracterização de tumores impalpáveis iniciais, objetivamos analisar o perfil genético (mutação) e epigenético (metilação de região promotora) de regiões do DNA relacionadas ao
gene supressor tumoral TP53, provenientes de biópsias de mulheres residentes do Estado do Rio de Janeiro. Neste trabalho, foram investigadas 34 amostras de tecido de tumor de mama, por sequenciamento de DNA, nos exons de 5 a 8 do gene TP53. Nesta região, não foi encontrada nenhuma mutação. Este resultado pode estar relacionado ao tipo inicial de lesão, de acordo com os dados radiológicos das lesões de categorias 3 e 4 da escala BIRADS. Para verificar o estado de metilação da região promotora do gene TP53, analisamos 30 pares de amostras (sangue e tumor) de pacientes com suspeita de câncer de mama, pela técnica MSP-PCR. Nenhuma amostra tumoral apresentou alteração no estado de metilação na região promotora do gene TP53, quando comparada à amostra normal. Um motivo possível para a
disparidade de resultados em relação à outros trabalhos pode ter sido a utilização da técnica. A caracterização das lesões impalpáveis apenas foi iniciada neste trabalho, no qual pudemos constatar que a mutação em TP53 pode ser um evento mais tardio. Portanto, a lesão mamária, em suas diferentes formas, continuará a ser o assunto investigado por nosso grupo, ampliando o número de amostras e alcançando melhor conexão da conduta e dos métodos clínicos já existentes, com as novas possibilidades de diagnóstico via marcadores moleculares em tumores e fluidos biológicos / Nonpalpable breast lesions that are often asymptomatic, may correspond to a stage of progression of the cancer that is difficult to be detected during routine screening. The only
possible way for their discovery is through breast images preventive examinations, generally mammography, which usually occurs after age 45. Because of these factors, impalpable lesions are often discovered when the developmental stage of the disease is already advanced and therapeutic interventions are less aggressive.This study aimed to characterize impalpable tumors by the analysis of genetic (mutation and instability) and epigenetic (methylation of the promoter region) of DNA regions related to TP53 tumor suppressor gene from impalpable lesions extracted from biopsies of women living in the state of Rio de Janeiro. Were investigated 34 tissue samples from breast cancer by DNA sequencing in exons 5-8 of TP53.
In this region, no mutation was found, this result may be related to the initial type of injury according to data of the radiological lesions of categories 3 and 4 of scale BIRADS . In order to check the status of methylation of the promoter region of the TP53 gene, we analyzed 30 pairs from samples (blood and tumor) of patients with suspected breast cancer, by MSPPCR technique. No tumor sample showed a change in the state of methylation in the promoter region of TP53 as compared to the normal sample. One possible reason for the disparity in the results between this study and the other studies may be related with the applied techniques.
The characterization of the nonpalpable lesions just started this work in which we could verify that the mutation in TP53 may be a later event. Therefore, the breast lesion, in its different forms, remains the subject investigated by this group. We have been worked for expanding the number of samples, so as to link the new possibilities of molecular diagnostics in clinical practice in tumors and biological fluids
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Grau de subestimação histopatológica por Core biopsy de lesões não-palpáveis da mama / EXTENT OF UNDERESTIMATION HISTOPATHOLOGICAL CORE BIOPSY BY INJURY NON-PALPABLE BREAST.Gonçalves, Aline Valadão Britto 31 March 2011 (has links)
Objective: The purpose of this study was to determinate the rate of underestimation of core biopsy (CB) of nonpalpable breast lesions, under image guidance, with validation at surgical excision histologic examination at Instituto Nacional de Câncer (INCA). Materials e methods: We retrospectively reviewed 352 CB that were submmited to surgery, from February 2000 to December 2005, and which histopathologic findings were at INCA database system. CB results were compared to surgical findings and underestimation rate was determined by dividing the number of lesions that proved to be carcinoma at surgical excision by the total number of high risk lesions and intracuctal carcinoma evaluated with excisional biopsy. Clinical, imaging, core biopsy and pathologic features were analyzed to identify factors that affect the rate of underestimation. Results: All patients were female, which mean age was 56,1 years old (26-86). Mass lesion was the most frequent finding (71,3%), being 69,9% less than 20mm, as well as BI-RADS® 4 (71,0%). The main guidance was stereotactic (57,1%), all using 14-gauge needles. The mean number of core samples was eight (4-22), being 99,7% at least five samples. The patients tolerated CB in 99,1% of cases, but bleeding occurred in 6,6%. The inconclusive CB findings occurred in 15,6%, (55/352). It was benign in 26,4%, high risk lesion in 12,8% and malignant in 45,2%. The segmentectomia was the more frequent surgery (70,2%), being benign in 26,7%, high risk in 18,2% and malign in 55,1%. There was agreement between CB and surgery in 82,1% (Kappa = 0,75). False-negative rate was 5,4% and the lesion was completely removed in 3,4%. Underestimation rate was 9,1%, and was associated with BI-RADS® 5 (p = 0,049), microcalcifications (p < 0,001) and stereotactic guidance (p = 0,002). All underestimated cases were less than 20 mm of diameter and there were at least five fragments. Underestimation rate of high risk lesions was 31,1% and there was no significant associations. Atypical ductal hyperplasia underestimation rate was 41,2% and there was not associations. Papillary lesions underestimation was 31,2% and was associated with stereotactic guidance (p = 0,036). Phyllodes tumor underestimation was 16,7% but it was not possible to make associations. There was one lobular neoplasia case that was concordant to surgery. Ductal carcinoma in situ underestimation was 41,9% and there was not significant associations. Conclusions: The core breast biopsy under image guidance is a reliable procedure but it remains the recommendation of surgical excision for high risk lesions detected at CB as well as it was not possible to assess clinical, imaging, core biopsy and pathologic features that could predict underestimation and avoid excision. Representative samples are much more important than number of fragments. / Objetivo: Determinar o grau de subestimação de core biopsy (CB), guiada por imagem, de lesões impalpáveis da mama e que foram subsequentemente submetidas à exérese cirúrgica no Hospital do Câncer III/ Instituto Nacional de Câncer (INCA). Materiais e métodos: Foram revisadas retrospectivamente 352 CB que foram submetidas à cirurgia entre fevereiro de 2000 e dezembro de 2005, e cujo laudo histopatológico estava registrado no sistema interno de informação do INCA. Os resultados da CB foram comparados com os da cirurgia e a taxa de subestimação foi calculada dividindo o número de carcinoma in situ e/ou invasivo à cirurgia pelo número de lesões de alto risco ou carcinoma in situ que foram submetidas à cirurgia. Foram analisadas características clínicas, imaginológicas, da CB e patológicas que poderiam influir na subestimação. Resultados: Todas as pacientes eram do sexo feminino, com média de idade de 56,1 anos (26-86). O nódulo foi o tipo de lesão mais frequente (71,3%) com 69,9% menor do que 20 mm, bem como BI-RADS® categoria 4 (71,0%). O tipo de guia mais utilizado foi a estereotaxia (57,1%), todos utilizando agulhas 14-gauge. O número médio de fragmentos foi de oito (4-22), com 99,7% apresentando pelo menos cinco fragmentos. O procedimento foi bem tolerado em 99,1% dos casos, mas ocorreu hematoma em 6,6%. A CB foi inconclusiva em 15,6%. O laudo histopatológico da CB foi benigno em 26,4%, lesão de alto risco em 12,8% e maligno em 45,2%. A segmentectomia foi a cirurgia mais frequente (70,2%), com laudo benigno em 26,7%, lesão de alto risco em 18,2% e maligno em 55,1%. A concordância entre a CB e a cirurgia foi de 82,1% (Kappa = 0,75). Falso-negativo foi de 5,4% e a lesão foi completamente removida em 3,4%. A taxa de subestimação foi de 9,1% e esteve associada com BI-RADS® categorias 5 (p = 0,049), microcalcificações (p < 0,001) e estereotaxia (p = 0,002). Todos os casos subestimados possuíam menos de 20 mm e em todos foram retirados pelo menos cinco fragmentos. A taxa de subestimação para lesões de alto risco foi de 31,1% e não apresentou variáveis associadas à subestimação. Já a taxa de subestimação de hiperplasia ductal atípica foi de 41,2% e também não houve associações. A subestimação de lesões papilíferas foi 31,2% e apresentou associação com estereotaxia (p = 0,036). Tumor filóides foi subestimado em 16,7%, mas não foi possível estabelecer associações. Houve apenas um caso de neoplasia lobular à CB que foi concordante com a cirurgia. A subestimação de carcinoma ductal in situ foi 41,9% e também não apresentou associações relevantes. Conclusões: CB guiada por imagem é um procedimento confiável, contudo permanece a recomendação de ressecção cirúrgica de lesões de alto risco detectadas à CB. Além disso, não foi possível estabelecer características clínicas, imaginológicas, da CB e patológicas que pudessem predizer subestimação e evitar a cirurgia. Amostras representativas da lesão são mais importantes que o número de fragmentos.
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Σύγκριση των αποτελεσμάτων της κλινικής εξέτασης της μαστογραφίας της βιοψίας δια λεπτής βελόνης και των προγνωστικών δεικτών σε ογκόμορφες αλλοιώσεις του μαστούΛυκάκη, Ελένη 07 July 2010 (has links)
Στις αρχές της δεκαετίας του 80 μια νέα εποχή ξεκινά για την Μαστογραφία και τον καρκίνο του Μαστού, με τη χρήση της τεχνικής "χαμηλής δόσης Μαστογραφίας", τη σωστή ενημέρωση των γυναικών για την πρόληψη του καρκίνου του μαστού και την εφαρμογή του πληθυσμιακού ελέγχου σε ασυμπτωματικές γυναίκες, με συνέπεια να αυξήσουν τον αριθμό των μη-ψηλαφητών και μη ψηλαφητών καρκίνων μαστού που διαγιγνώσκονται σε πρώιμα στάδια (0, Ι, ΙΙ, ΙΙΙΑ κλπ) με καλλίτερη πρόγνωση και θεραπεία.
Προηγούμενες κλινικές μελέτες προσπάθησαν να συσχετίσουν τα ακτινολογικά με τα ιστολογικά χαρακτηριστικά του καρκίνου του μαστού αλλά δεν κατάφεραν να αναδείξουν σημαντικές διαφορές όσον αφορά τα ιστολογικά και βιολογικά χαρακτηριστικά μεταξύ των συμπωματικών και των μαστογραφικά εντοπιζόμενων μη ψηλαφητών καρκινωμάτων του μαστού .
Επιπλέον, αρκετοί ερευνητές φαίνεται να καταλήγουν στο συμπέρασμα ότι τα καλά προγνωστικά χαρακτηριστικά των καρκινωμάτων του μαστού που αναδεικνύονται με την προληπτική μαστογραφία σχετίζονται άμεσα ή έμμεσα με την επίδραση βιολογικών παραγόντων.
Σκοπός της παρούσας μελέτης είναι η ανάδειξη των δεικτών που σχετίζονται με την μαστογραφική απεικόνιση της κακοήθων ογκόμορφων αλλοιώσεων ψηλαφητών και μη και της επιθετικότητας της νόσου.
Μελετήθηκαν συνολικά πεντακόσιες εβδομήντα τέσσερεις ογκόμορφες αλλοιώσεις ψηλαφητές ή μη του μαστού σε πεντακόσιες εβδομήντα ασθενείς που εντοπίστηκαν κατά τη διάρκεια του μαστογραφικού ελέγχου στο εργαστήριο μας κατά την περίοδο 1994- 2004. Όλοι οι ασθενείς υποβλήθηκαν σε βιοψία δια λεπτής βελόνης (FNA) ή κατευθυνόμενη από με μαστογραφία χειρουργική βιοψία.
Η ιστολογική εξέταση ανέδειξε 410/574 (71,4%) κακοήθεις ογκόμορφες αλλοιώσεις και 164/574 (28,5%) καλοήθεις. Ανοσοϊστοχημεία πραγματοποιήθηκε σε τομές παραφίνης σε 390 από τις 410 κακοήθεις αλλοιώσεις χρησιμοποιώντας μία ποικιλία μονοκλωνικών και πολυκλωνικών αντισωμάτων ενάντια στις εξής πρωτεϊνες: ER, PR, p53, HER-2,Ki 67 και KATH D.
Οι κακοήθεις ογκόμορφες αλλοιώσεις ταξινομήθηκα από την Μαστογραφική τους απεικόνιση (σύμφωνα Breast Imaging Reporting and Dada System BI RADS) σε τρείς κατηγορίες : στην κατηγορία Β (οι αστεροειδείς κακοήθεις ογκόμορφες αλλοιώσεις) ήταν το (44,8%), στην κατηγορία Α (οι άτονες με ασαφή ή εν μέρει ασαφή όρια) το 36% και στην κατηγορία Γ (σκιάσεις και αποτιτανώσεις) που ήταν 18,2% όλων των κακοήθων ογκόμορφων αλλοιώσεων.
Η ανάλυση των αποτελεσμάτων μεταξύ της μαστογραφικής απεικόνισης των κακοήθων ογκόμορφων αλλοιώσεων και των ιστολογικών και βιολογικών χαρακτηριστικών των ανέδειξε :
Σημαντική συσχέτιση της μαστογραφικής απεικόνισης με το μέγεθος των ογκόμορφων αλλοιώσεων (p=0.01<0.05). Σημαντική συσχέτιση με το βαθμό διαφοροποιήσεως της κακοήθειας (p=0.005<0.05). Σημαντική συσχέτιση με την έκφραση των πρωτεϊνών p53 (p=0.015) και Ki -67( p=0.02).
Δεν παρατηρήθηκε σημαντική συσχέτιση της απεικόνισης των ογκόμορφων αλλοιώσεων με την ηλικία των ασθενών (p=0.08>0.05), με την ανίχνευση πυρηνικής θετικότητας για τους οιστρογονικούς (ER) και τους προγεστερονικούς(PR) υποδοχείς (p =0.4>0.05) καθώς και με τις πρωτεΐνες HER-2. και KATH D.
Επίσης παρατηρήθηκε οριακή συσχέτιση στην απεικόνιση των κακοήθων ογκόμορφων αλλοιώσεων και των λεμφαδένων.
Συμπερασματικά βρήκαμε ότι η κατηγορία Β με τις αστεροειδείς ογκόμορφες αλλοιώσεις είχε ευνοϊκότερη επίδραση από τ η κατηγορία Α με τις άτονες με ασαφή ή εν μέρει ασαφή όρια και με τις ογκομορφές αλλοιώσεις και αποτιτανώσεις (κατηγορία Γ).
Οι άτονες με ασαφή ή με εν μέρει ασαφή όρια κακοήθεις ογκόμορφες αλλοιώσεις(κατηγορία Α) σχετίζονται με χαμηλής διαφοροποίηση κακοήθεια (grade 3) με υπερέκφραση του p53 και Ki -67 και με αρνητικούς υποδοχείς (PR και ER). Οι όγκοι αυτοί είναι μεγάλοι όγκοι με ίδια πολλές φορές μαστογραφική απεικόνιση με εκείνη των καλοηθών ογκόμορφων αλλοιώσεων. / At the beginning of 80 a new era for the Mammography and the breast cancer started with the use of the technique "low dose Mammography", with the correct information of women for the prevention of the breast cancer and the application of mass screening in asymptomatic women, with the result to increase the number of palpable and no- palpable breast cancers diagnosed in early stages (0,I,II,IIIA etr) with better prognosis and therapy.
Previous clinical studies have attempted to correlate the radiological with the histological characteristics of breast cancer but did not succeed to show significant differences as for us the histological and biological characteristics among the symptomatic and the mammographically localized non- palpable breast cancers.
Furthermore, many investigators see to conclude that the best prognostic characteristics of breast cancers that are identified with the preventive mammography are directly or indirectly related by the effect of biological factors.
The aim of the present study is to mark out indicators that are related with the mammographic appearance of malignant palpable and no- palpable lesions and the aggressiveness of disease.
In total five hundred seventy four palpable and no- palpable breast lesions have been studied in five hundred seventy patients that were localized during the mammographic screening in our department, between 1994 to 2004. All the patients were subjered to line needle biopsy (FNA) or mammographically guided open surgical biopsy.
Histological examination showed 410/574 (71.4%) malignant lesions and 164/574 (28.5%) benign lesions.
Immunohistochemistry was performed in paraffin sections in 390 of 410 malignant lesions using a variety of monoclonal and polyclonal antibodies against the following proteins ER,PR, P53, HER-2, Ki67and KATH D.
The malignant lesions were classified from their mammographic appearance (according to Breast Imaging Reporting and Dada System BI RADS) in three categories: category A (lesions with poorly defined or partially poorly defined margins)were 36%, category B (speculated malignant lesions) were 44.8% and category C (lesions wih calcifications) were 18.2% of all malignant lesions.
The analysis of our results between the mammographic appearance of the malignant lesions and their histological and biological characteristic showed the following:
1) Significant correlation existed between the mammographic appearance and the size of the lesions (p=0.01<0.05).
2) Significant correlation existed with the degree of differentiaton of malignancy (p=0.005<0.05).
3) Significant correlation existed with over expression of proteins P53 (p=0.015). and Ki- 67 (p=0.02).
No significant correlation was observed between the appearance of lesins with the age of the patients (p=0.08>0.05), with the detection of nuclear positivity of the estrogens (ER) and progesterone (PR) receptors (p=0.4>0.05) and also with the proteins HER-2 and KATH D.
Furthermore a bode line correlation was observed between the appearance of the malignant lesions and lymph notes.
In summary, it was found that the category B patients with the speculated lesions had a more favorable effect than category A with the poorly defined or partially poorly defined limits, and the category C lesions with calcifications.
The poorly defined or partially poorly defined limits malignant lesions (category A) are related with low grade malignancy (grade 3, with over expression of P53 and Ki-67 and with negative receptors (PR and ER). These are large size lesions and are difficulty diagnosed from benign lesions.
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Uma nova abordagem de descritor de textura baseada em transformada ripplet para classificação de lesões da mamaMoreira Junior, Wagner Lopes January 2018 (has links)
Orientador: Prof. Dr. Marcelo Zanchetta do Nascimento / Coorientadora: Profa. Dra. Ana Lígia Scott / Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Engenharia da Informação, Santo André, 2018. / Nos últimos anos a ciência vem contribuindo significativamente para o avanço no diagnóstico precoce de doenças, através da análise de imagens médicas. As novas tecnologias de geração de imagens, através da digitalização, trazem a possibilidade de geração de uma gama de imagens que antes era inviável do ponto de vista econômico. Com esse avanço, a quantidade de informações que cada paciente gera é extensa, aumentando consideravelmente o trabalho de investigação manual. Por isso, a necessidade de se desenvolver soluções automatizadas para análise dessas imagens. Sem contar que essas soluções introduzem um fator de precisão mais acurado, que podem contribuir com uma segunda opinião. As abordagens no domínio da frequência para extração de características de textura, utilizadas largamente para identificação de características de imagens de mama, fazem uso da Transformada Wavelet em conjunto com outros extratores. No entanto, a Wavelet é muito eficiente para identificar características em uma abordagem 1D, o que dificulta a descrição de bordas e contornos. A Transformada Ripplet-II vem justamente para resolver tais lacunas, ou seja, demonstra ser uma técnica capaz de obter informações de textura de imagens com maior precisão, como demonstra os estudos mais recentes. Este trabalho apresenta a investigação da transformada Ripplet-II em imagens histológicas de lesões de mama, para demonstrar a eficácia dessa abordagem na distinção dos grupos de lesões benignas e malignas. O método proposto utilizou um filtro CLAHE, de equalização de histogramas, na etapa de pré-processamento, antes da extração dos descritores resultantes da aplicação da Ripplet-II. Obteve-se ainda características derivadas da Matriz de Co-ocorrência, que foram combinadas com os descritores Ripplet-II. Como resultado da classificação das imagens, utilizando-se o ReliefF como seletor e o Random Forest como classificador. Na fase dos experimentos, uma comparação foi realizada entre descritores Wavelet e Ripplet-II, com valores de acurácia de 88,46% e 96,15%, respectivamente. A aproximação proposta mostra resultados promissores como uma técnica para classificação de lesões em imagens histológicas de mama. / In recent years, science has been contributing significantly to the advance in the early diagnosis of diseases, through the analysis of medical images. The new technologies of imaging, through the digitalization, bring the possibility of generating a range of images that previously was impracticable from the economic point of view. With this advance, the amount of information each patient generates is extensive, greatly increasing the manual research work. Therefore, the need to develop automated solutions to analyze these images. Not to mention that these solutions introduce a factor of precision, that can contribute to a second opinion. Frequency approaches for extracting texture characteristics, widely used for identification of breast imaging characteristics, make use of the Wavelet Transform in conjunction with other extractors. However, Wavelet is very efficient at identifying features in a 1D approach, which makes it difficult to describe edges and contours. The Ripplet-II Transform comes precisely to solve such gaps, that is, it proves to be a technique capable of obtaining information of texture of images with greater precision, as it demonstrates the most recent studies. This work presents the investigation of the Ripplet-II transform in histological images of breast lesions, to demonstrate the effectiveness of this approach in distinguishing groups of benign and malignant lesions. The proposed method used a CLAHE histogram equalization filter in the preprocessing step before extracting the resulting descriptors from the Ripplet-II. We also obtained features derived from the Co-occurrence Matrix, which were combined with the Ripplet-II descriptors. As a result of the classification of the images, using ReliefF as selector and Random Forest as a classifier. At the stage of the experiments, a comparison was carried out between Wavelet descriptors and Ripplet II, with accuracy values of 88.46% and 96.15%, respectively. The proposed approach shows promising results as a technique for lesion classification in histological breast imaging.
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