Isolated uncertain tympanic membrane findings. Central site of tympanic membrane cholesteatomas

Ohne Zusammenfassung     

Galectin-1, -3, -7 expressions in congenital and acquired pediatric cholesteatomas compared to external auditory canal skin

Objectives

There is a classical distinction based on clinical criteria between acquired and congenital cholesteatomas. To determine if these two types of lesions show different immunohistochemical features, we have studied the expression patterns of three distinctive galectins (animal lectins implied especially in cellular proliferation and apoptosis) in both types of cholesteatomas and compared it to their expression patterns in external auditory canal skin.

Methods

Our study is based on nine acquired and eight congenital cholesteatomas, obtained from children during ear surgery. Six specimens of normal adult auditory meatal skin served as control. Specimens were analyzed by immunohistochemistry using monoclonal antibodies with galectin-1 and galectin-3, and a polyclonal antibody with galectin-7.

Results

We did not observe any differences in the galectin distribution pattern between congenital and acquired pediatric cholesteatomas. Compared to the control group, cholesteatomas present some particular features. There was no expression of galectin-1 and a lower expression of galectin-3 in the epithelium. Furthermore, we observed a preferentially nuclear distribution of galectin-7 in cholesteatomas, whereas it is essentially cytoplasmic in the control group.

Conclusion

The data reported in this study suggest, on the basis of a lesser marked galectin-3 in cholesteatomas epithelium compared with an external auditory canal skin, that an immature keratinocytes population is at the origin of these lesions and that galectin-3 and galectin-7 play a part in the capacity as apoptosis modulators. Our study does not establish a difference in the galectin expressions of congenital and acquired cholesteatomas, but it constitutes however an additional argument in favor of the "undifferentiated" origin of keratinocytes in cholesteatomas.     

喉癌引流淋巴结中巨噬细胞对自体肿瘤杀伤活性检测

本实验采作细胞培养技术,从喉癌患者颈廓清淋巴结中提取的巨噬细胞（Mphi）作效应细胞,喉癌患者自体癌细胞及K562细胞作靶细胞,分别混合培养（两组均加PHA作为刺激原）,结果表明：喉癌患者颈部肿大淋巴结Mphi对自体癌细胞（35例）及K562细胞（30例）均有杀伤能力;此外,我们还对比了未转移淋巴结（N0组,18例）与转移淋巴结（N+组,17例）MPhi杀伤能力,结果N0组高于N+组,差异非常显著（P＜0．01）。结果提示,喉癌患者颈部引流淋巴结中尚存在着免疫活性细胞,并具有肮肿瘤免疫潜能,该实验为临床合理实施颈廓清术及将活化的Mphi应用于肿瘤免疫治疗提供理论依据。     

Detection of human papillomavirus in cholesteatomas

The presence of human papillomavirus DNA in cholesteatoma may have some role in the development of middle ear cholesteatoma as well as in papilloma. In the present study, polymerase chain reaction and in situ hybridization with human papillomavirus (HPV)-6 and ¶-11 DNA probes were used to detect the presence of HPV DNA in 32 human middle ear cholesteatomas. Only one specimen contained HPV-6 DNA. Although its occurrence may have been coincidental, it is also possible that the hyperproliferative epithelium of cholesteatomas might have some relationship with HPV infections.     

Evidence for microbial biofilms in cholesteatomas

BACKGROUND: Sessile bacteria within biofilms are highly resistant to eradication by antimicrobial agents. Previously, we have shown that the most common organisms cultured from experimentally induced cholesteatomas are biofilm formers. Additionally, the keratin "matrix" of a cholesteatoma is an ideal environment for the support of biofilm formation. OBJECTIVE: To determine if microbial biofilms occur within the keratin matrix of infected cholesteatomas. DESIGN: We evaluated the histomorphologic characteristics of 24 human and 22 experimental cholesteatomas for evidence of biofilm formation using light and transmission electron microscopy. SUBJECTS: Human tissues were collected during surgical eradication of existing cholesteatomas. Twenty-two gerbil cholesteatomas were either spontaneously occurring or induced by external auditory canal ligation and harvested several months later. RESULTS: Gram-positive and gram-negative bacteria were seen within acellular deposits among the keratin accumulations in 21 of 22 gerbil and 16 of 24 human cholesteatomas. Regions of accumulated bacteria possessed the ultrastructural appearance of typical amorphous polysaccharide biofilm matrix. CONCLUSIONS: There is strong anatomic evidence for the presence of bacterial biofilms in experimental and human cholesteatomas. The existence of bacterial biofilms within cholesteatomas may explain the clinical characteristics of infected cholesteatomas, that is, persistence and recurrence of infection, with surgical eradication being the only effective treatment.     

Keratinization of middle ear cholesteatomas

Summary A histochemical study was performed to determine the involvement of epidermal transglutaminase (ETgase) in the keratinization of middle ear cholesteatomatous lesions, and to compare it with its role in the middle ear mucosa and epidermis. In a first assay, we localized the (E)Tgase activity in situ. A second immunohistochemical assay revealed the distribution of the particulate form of ETgase, which is involved in cross-linked envelope formation. A remarkable difference between strongly keratinized epidermal tissues and the cholesteatoma matrix is the frequent observation in the latter of the remnants of (E)Tgase activity in cytosol, even in advanced stages of differentiation. As a consequence, the cell-membrane-associated ETgase activity, and thus the extent of cross-linking within the envelope, is at a lower level than expected. This aspect is reminiscent of the keratinization phenomenon manifested by thin epidermal tissues. In addition, our findings are the first to show that ETgase is a substantial marker of middle ear mucosa.This paper is dedicated to the memory of Prof. E. Gillis, deceased 3 August 1988, aged 51. His guidance will be sorely missed by those who knew and worked with him.     

Surgical treatment of pediatric cholesteatomas

OBJECTIVE:: Management of pediatric cholesteatomas remains controversial. We reviewed our 16-year experience in the surgical treatment of cholesteatomas in children and describe a treatment paradigm. STUDY DESIGN:: The authors conducted a retrospective review. METHODS:: A total of 106 mastoidectomies (86 for an acquired cholesteatoma and 20 for a congenital cholesteatoma) were performed in children 16 years old and younger from 1988 to 2003. Follow up ranged from 2 years to 12 years with a mean follow-up period of 6 years. Hearing outcomes, cholesteatoma recidivism, and dry mastoid cavity were the main outcomes measured. RESULTS:: Seven (7%) patients had revision surgery for cholesteatoma recidivism. Rates of cholesteatoma recurrence for canal all up (CWU) and canal wall down (CWD) mastoidectomy groups were similar (8% vs. 6%). The percentage of patient with good serviceable hearing (pure-tone average 相似文献   

Langerhans cells in human middle ear cholesteatomas

Summary Langerhans cells have been found in cholesteatomas for many years. It is believed that they are immunocompetent cells and have the same role in cell-mediated immunologic mechanisms in cholesteatoma as well as in skin. This study used the transmission electron microscope to observe the cellular characteristics of Langerhans cells and the apposition phenomenon of Langerhans cells with lymphocyte-like cells in human middle ear cholesteatomatous tissue. These findings are evidence for cell-mediated immune responses in middle ear cholesteatomas. In vitro Langerhans cells conditioned medium prepared from Lewis rat skin was used to show its effects on protein synthesis and the differentiation of basal cells. Since the cellular behaviour of basal cells is important in the development and pathogenesis of cholesteatoma, the present study shows that Langerhans cells may have some role in the clinical formation of a cholesteatoma. Since cells extracted from rat skin may have a different response from that of cells from human middle ear cholesteatoma, further investigations are necessary to compare the biological effects of both tissues. Correspondence to: W.-Y. Chao     

Prevalence of human papillomavirus DNA in cholesteatomas

Cholesteatomas show histomorphological features like papillary growth and koilocytosis, which are characteristic of lesions induced by human papillomaviruses (HPV). Two previous studies investigating the possible role of HPV in the development of cholesteatoma had detected HPV-6 and HPV-11 DNA with a prevalence differing from 3 to 36%. The aim of the presented study was to evaluate the prevalence of different HPV types in cholesteatomas using a sensitive detection system for HPV DNA. Twenty-nine biopsies from cholesteatomas were screened for HPV DNA with a 2-step broad-spectrum PCR (PCR and nested PCR). HPV-positive products were directly sequenced by means of a cycle sequencing approach. Sensitivity of the applied broad-spectrum PCR was 0.1 copy/genome. One out of 29 biopsies showed a positive signal on the nested PCR level. Considering the low prevalence (1/29 biopsies) of detected HPV DNA in cholesteatomas, infections with common HPV types are unlikely to be a causative factor.     

Anatomical and surgical particularities of cholesteatomas in children

Summary In children, cholesteatoma is closely related to dysfunction of the eustachian tube and evolves inside a malleable temporal bone. The importance of auditory and speech functions in such patients has caused us to use a very particular clinical philosophy. At the present time we have studied 154 cases of cholesteatomas in children under 15 years old. The following three points have been shown: the pathogenesis of a cholesteatoma can be of the primary type, secondary (due to an unfavorable extension of retraction pocket or to squamous cell migration) or even be iatrogenic; anatomical and clinical findings (with X-ray studies) predicate the treatment used; surgical treatment frequently requires a second-look operation.Presented at the First European Congress of Oto-Rhino-Laryngology and Cervico-Facial Surgery, Paris, 26–29. September     

凋亡抑制蛋白Survivin及Bcl-2在中耳胆脂瘤上皮中的表达及意义

目的研究凋亡抑制蛋白Survivin及Bcl-2在中耳胆脂瘤上皮中的表达及相互关系,探讨其表达对胆脂瘤增殖能力的影响。方法运用免疫组织化学SP法检测21例胆脂瘤标本及11例外耳道骨部正常皮肤组织中Survivin、Bcl-2的表达。结果Survivin、Bcl-2在胆脂瘤上皮的表达与正常外耳道皮肤上皮比较,不仅范围广,基底上层也有表达,而且表达水平显著增高,两者比较有统计学意义(P<0.01)。胆脂瘤上皮中Survivin表达指数与Bcl-2表达指数呈正相关(r=0.553,P<0.01)。结论凋亡抑制蛋白Survivin,Bcl-2在中耳胆脂瘤的异常表达可能在胆脂瘤的发生、发展过程中起重要作用,它们可能参与胆脂瘤上皮的凋亡调控过程,因此适当控制Survivin,Bcl-2的表达可能会更有效地控制中耳胆脂瘤的发展。     

Clinical and surgical aspects of cholesteatomas in children

A review of 101 charts of pediatric patients who underwent surgery for cholesteatoma in the Hospital das Clínicas, S?o Paulo, Brazil, showed that the peak incidence was in the 10- to 15-year-old age group (mean age, 10.7 years). A high incidence of complications (45.5%) and a significant functional impairment (air-bone gap greater than 40 dB in 49% of patients) were some of the particular features of our patients. Radical or modified radical mastoidectomies were performed in 75 cases (74.3% of cases). The open technique was chosen primarily to eradicate cholesteomatous disease, but the satisfactory functional results also achieved support our preference for this technique.     

Expression patterns of cytokeratins in retraction pocket cholesteatomas

OBJECTIVES: To investigate the patterns of cytokeratin (CK) expression in retraction pocket cholesteatoma. STUDY DESIGN: An animal model study. METHODS: Retraction pocket cholesteatomas were induced by electrocautery of the eustachian tube orifice in 24 mongolian gerbils. They were divided into normal and cholesteatoma groups of clinical stages I to IV. The antibodies to pan-cytokeratin CK 1/10, CK 5/6, CK 4, and CK 13/16 were used for immunohistochemical staining. The intensity of staining in each group as measured with densitometry was compared regarding anatomical sites and clinical stages. RESULTS: In retraction pocket cholesteatoma, CK expression was altered only at focal sites such as the pars tensa of the tympanic membrane. The change of CK expression was observed only at certain stages of cholesteatoma formation. In keratinocytes from cholesteatomas, CK 13/16 was overexpressed compared with control specimens, indicating hyperproliferation. The site with the most prominent change in retraction pocket cholesteatoma was somewhat different from that in canal ligation cholesteatoma in a previous study. CONCLUSIONS: The results suggested that aural cholesteatoma is a disease with a spectrum of pathological conditions and that the transmigration and hyperproliferation process of squamous epithelium occurs in areas adjacent to the cholesteatoma.     

Histopathological findings in parotid gland metastases from renal cell carcinoma

Metastatic tumours involving the parotid gland arising from non-head and neck origin are rare. Immunohistochemistry has improved the differential diagnosis of these lesions. Current immunohistochemical markers allow the distinction between a number of potential primary tumours (e.g., lung, kidney and breast). We present the clinical and histomorphological features of three renal cell carcinoma (RCC) patients presenting with a parotid mass, review the literature of various non-head and neck malignancies metastasizing to the parotid gland, and discuss their differential diagnosis. Two females and one male, aged 58 to 76 years, presented with a parotid tumour of renal cell origin. In one case, the parotid mass was the first clinical manifestation. In the two other cases, a nephrectomy had been performed 5-9 years earlier because of RCC. The cases showed a highly vascular parotid lesion causing difficulty in interpretation of the fine needle aspirate. Two patients underwent a superficial parotidectomy and one patient an open biopsy of the parotid gland tumour. Immunohistochemical stainings for vimentin, CD10 and PNRA were positive suggesting renal cell origin, which was later confirmed. Clinical and radiological evaluations and diagnosis by fine needle aspiration may prove difficult partly due to the vascular nature of parotid metastasis of renal cell carcinoma. Immunohistochemical staining is useful in identifying the primary tumour.