Immunohistochemical localization of d-ß-aspartic acid in congenital and acquired middle ear cholesteatoma.

Objective/Hypothesis: Middle ear cholesteatoma is characterized by abnormal growth of the keratinizing squamous epithelium of the temporal bone. d-ß-aspartic acid is the major isomer of d-aspartic acid found in elderly tissue. We assessed the immunoreactivity to k-ß-aspartic acid of congenital and acquired middle ear cholesteatomas. Study Design: Case-control studies. Material and Methods: Tissue samples were collected from 21 patients comprising 21 ears with congenital middle ear cholesteatoma and 26 patients comprising 29 ears with acquired type. Their clinical and histopathological features were investigated. We divided the middle ear cholesteatoma samples into three layers: the perimatrix, matrix, and cystic contents. The patterns of immunoreactivity to d-ß-aspartic acid expression were then assessed immunohistochemically. Results: Two patterns of immunoreactivity to d-ß-aspartic acid were detected in middle ear cholesteatoma: infiltrative and diffuse. In congenital middle ear cholesteatoma, d-ß-aspartic acid expression was observed throughout all the layers (perimatrix, matrix, and cystic contents), and immunoreactivity to d-ß-aspartic acid was dramatically strong in all layers. The expression levels of d-ß-aspartic acid to the cystic content and perimatrix were significantly higher in congenital middle ear cholesteatoma than in the acquired type. Conclusions: This study showed the expression levels of d-ß-aspartic acid in middle ear cholesteatoma to differ significantly between congenital and acquired middle ear cholesteatoma. Our results indicate that overexpression of d-ß-aspartic acid is likely to be involved in the pathogenesis of cholesteatoma, and we speculate that d-ß-aspartic acid could be a novel biomarker for, and a therapeutic target in, congenital and acquired middle ear cholesteatoma. Level of Evidence: 4.

Perimatrix of middle ear cholesteatoma: A granulation tissue with a specific transcriptomic signature.

OBJECTIVES/HYPOTHESIS: To establish comprehensive transcriptomic profiles of cholesteatoma perimatrix tissue and granulation tissue from chronic otitis media (COM) that did not develop cholesteatoma, which can indicate molecular pathways involved in the cholesteatoma perimatrix pathology and invasiveness. STUDY DESIGN: Retrospective Case Series. METHODS: Transcriptome data were obtained from cholesteatoma perimatrix tissue and COM granulation tissue by an Illumina iScan microarray. Differentially expressed genes (DEGs) were subsequently analyzed using both bioinformatical functional annotation and network analysis. Expression of candidate genes (MMP9 and LCN2) was validated by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) on a larger group of samples. RESULTS: Analysis of the transcriptome led to the identification of 169 differentially expressed genes between investigated tissues. Bioinformatic analysis suggested that most significant biological processes involving DEGs were previously described in cholesteatoma pathology. Network analysis identified ERBB2, TFAP2A, and TP63 as major hubs of the DEGs molecular network. Furthermore, it was observed that the cellular component most significantly enriched in DEGs was extracellular space containing 47 DEGs. Using qRT-PCR, it was confirmed that mRNA levels of the major extracellular hub (MMP9) are increased, whereas its interacting molecule (LCN2) mRNA levels were decreased in cholesteatoma perimatrix tissue compared to COM granulation tissue. CONCLUSIONS: The current study approach offers an overall look at molecular mechanisms that describe the cholesteatoma entity by focusing exclusively on the perimatrix processes in comparison to COM granulation tissue. The observed differences in gene expression between cholesteatoma perimatrix and COM granulation tissue could suggest novel markers potentially influenced by the perimatrix-matrix molecular interplay, which is not present in COM without cholesteatoma. LEVEL OF EVIDENCE: NA Laryngoscope, 130:E220-E227, 2020.

Histopathological evaluation and long-term results of soft tissue preservation technique in cholesteatoma surgery.

The goal of cholesteatoma surgery is total removal of the cholesteatoma matrix and prevention of recurrence. Preservation of soft tissue in the attic is reported to improve post-operative middle ear aeration, and thus prevents recurrence. However, the histology and nature of the preserved tissue have rarely been reported. The aim of this study is to clarify the histology of the preserved soft tissue in cholesteatoma surgery, and to show its relationship to the clinical course. Surgical specimens were obtained from ten patients with pars flaccida-type cholesteatoma. In these patients, cholesteatoma occupied the attic and the mastoid cavity. The cholesteatoma was removed so as not to expose the bone in the attic. After the removal of the lesions, soft tissue was harvested from the floor of the attic, using cupped forceps. The specimens were fixed with 10 % formalin, and stained with hematoxylin-eosin. The patients were followed-up for 8 years after the surgery. No patients showed post-operative inner ear disturbance or facial nerve palsy. In one patient, residual lesion was found during the revision surgery. The area of residual lesion was not explored during the first operation. Two other patients showed recurrent cholesteatoma in the pars tensa; one of these patients had accompanying otorrhea. The other seven patients showed no residual or recurrent cholesteatoma 8 years after the surgery. The histological examination showed that the harvested tissue was mainly composed of collagen fiber and fibroblasts. Ciliary epithelial cells were found in one patient. In three patients, cysts of mucosal remnants (glandular cysts), were embedded in the connective tissue. Two of these three patients experienced recurrent cholesteatoma, while the other seven patients were without recurrence at follow-up. Preservation of soft tissue behind the cholesteatoma matrix is a safe technique if the surgical field is fully visible. In most cases, the preserved tissue was fibrous connective tissue and lacked the characteristics of mucosa. The glandular cysts in the preserved soft tissue seem to be related to the recurrence of cholesteatoma.

Correlação da cadeia ossicular no transoperatório com achados histológicos de colesteatomas / Hystology findings' correlation between the ossicular chain in the transoperative and cholesteatomas

A Otite Média Crônica é definida pela presença de alterações teciduais inflamatórias irreversíveis na fenda auditiva. As lesões ossiculares são as mais prevalentes. OBJETIVO: Correlacionar o grau de comprometimento da cadeia ossicular, visualizada no transoperatório, com o grau histológico de inflamação e com a espessura da perimatriz de colesteatomas. TIPO DE ESTUDO: Estudo transversal. MÉTODOS: Descrições cirúrgicas de 71 pacientes foram revisadas. Colesteatomas coletados e fixados em formol 10 por cento e preparadas uma lâmina em Hematoxilina-Eosina e outra em Picrossírios. A leitura foi "cega", através de imagens digitais, no ImageProPlus. A análise estatística foi realizada através do coeficiente de Spearman, sendo considerados como estatisticamente significativos os valores de P≤0,05. RESULTADOS: Havia algum envolvimento da cadeia ossicular em 65 casos. O ossículo mais freqüentemente afetado era a bigorna, seguida pelo estribo e pelo martelo. Ao aplicarmos o coeficiente de Spearman entre o grau de comprometimento da cadeia ossicular com a idade do paciente à cirurgia, a espessura da perimatriz e o grau histológico de inflamação não foram detectadas correlações. CONCLUSÃO: Os nossos achados indicam que é praticamente universal o acometimento da cadeia ossicular na presença de colesteatoma. Não foi encontrada correção entre a erosão ossicular e os achados histológicos.

Chronic otitis media is hystopathologycaly defined as the presence of irreversible inflammatory tissue changes in the middle ear. Ossicular lesions represent the most prevalent change. AIM: to correlate the degree of ossicular chain changes seen during surgery with the inflammatory histological degree and the thickness of the cholesteatoma perimatrix. STUDY DESGN: Cross-sectional study. METHODS: Seventy-one descriptions of surgeries done in patients submitted to tympanomastoydectomy were reviewed. Cholesteatoma were collected and fixed in 10 percent formaldehyde. Two slides were made for each cholesteatoma, one stained with HE and another with picrossirius. Images were obtained from light microscopy and digitally processed and "blindly" analyzed using Image Pro-Plus Software. For statistical analysis we used Spearman's coefficient. Differences were considered statistically significant if P≤0.05. RESULTS: the ossicular chain was involved in 65 cases. The incus was the most frequently affected bone, followed by the stapes and the malleus. When the Spearman's coefficient was employed considering ossicular chain change degree with patient's age by the time of surgery, perimatrix thickness and histological degree of inflammation, correlations were not established. CONCLUSION: Our findings indicate that ossicular chain changes are practically universal when a cholesteatoma is present. We didn't find correlations related with bone erosion and cholesteatoma's histological findings.

Descrição histológica de colesteatomas adquiridos: comparação entre amostras de crianças e de adultos / Histologic description of acquired cholesteatomas: comparison between children and adults

O colesteatoma é constituído de matriz, perimatriz e conteúdo cístico. Alguns autores afirmam que, em crianças, seu comportamento clínico é mais agressivo do que em adultos. OBJETIVOS: Comparar histologicamente colesteatomas de crianças e adultos. METODOLOGIA: Foram analisados 74 colesteatomas, sendo 35 de pacientes pediátricos (<18 anos) e 39 de adultos (>18 anos). Foram avaliados o número de camadas celulares e hiperplasia na matriz; espessura, epitélio delimitante, fibrose, inflamação e granuloma na perimatriz. A análise estatística foi realizada com o programa SPSS 10.0, utilizando os coeficientes de Pearson e de Spearman, testes t e de qui-quadrado. O número de camadas celulares na matriz foi de 8,2±4,2. A hiperplasia aparece em 17 por cento, a fibrose em 65 por cento, o granuloma em 12 por cento e o epitélio delimitante em 21 por cento. A perimatriz apresentou uma mediana de 80 micrômetros (37 a 232), valor mínimo zero e valor máximo 1.926. O grau histológico de inflamação foi considerado de moderado a acentuado em 60 por cento. Ao aplicarmos o coeficiente de Spearman entre o grau de inflamação e média de camadas celulares da matriz com as variáveis sumarizadoras da medida de espessura da perimatriz encontramos correlações, significativas, com magnitudes de moderadas a grandes (rs=0,5 e P<0,0001). CONCLUSÃO: Não foram identificadas diferenças morfológicas entre os colesteatomas de adultos e crianças. Encontramos correlação entre a intensidade da inflamação e da média de camadas celulares da matriz com a espessura da perimatriz, o que pode predizer sua agressividade, mais estudos são necessários para definir o papel deste achado na patogênese do colesteatoma.

Cholesteatoma is constituted of matrix, perimatrix and cystic content. Some authors affirm that, in children, its clinical behavior is more aggressive of the than in adults. AIMS: Histologic compared cholesteatomas of children and adults. METHODOLOGY: 74 cholesteatomas been analyzed, being 35 of pediatrics patients (<18 years). The average number of cellular layers and hyperplasia in the matrix had been evaluated; thickness, delimitante epithelium, fibrosis, inflammation and granuloma in the perimatrix. The analysis statistics was carried through with program SPSS 10,0, using the coefficients of Pearson and Spearman, test of qui-square and t test. The number of cellular layers in the matrix was of 8,2±4,2. The hyperplasia appears in 17 percent, fibrosis in 65 percent, granuloma in 12 percent and the delimitante epithelium in 21 percent. The perimatrix presented a medium one of 80 micrometers (37 the 232), minimum value zero and maximum value 1.926. The histological degree of inflammation was considered of moderate the accented one in 60 percent. When applying the coefficient of Spearman enters the inflammation degree and average of cellular layers of the matrix with the variables of the measure of thickness of the perimatrix we find correlations, significant, with moderate magnitudes of the great ones (rs=0,5 and P<0,0001). CONCLUSION: Adults colesteatomas of and child had not been identified to morphologic differences between. We find correlation enters the intensity of the inflammation and of the average of cellular layers of the matrix with the thickness of the perimatrix, what it can predict its aggressiveness, more studies are necessary to define the paper of this finding in pathogenesis of cholesteatoma.