Residual vestibular function after vestibular schwannoma surgery.

OBJECTIVES: This study aimed to assess vestibular function in 39 patients who underwent neurectomy for vestibular schwannoma. METHOD: Semicircular canal reactivity was measured by video head-impulse test using high-frequency passive head acceleration. Response gain was calculated as a ratio between the areas under the eye-velocity curve and the head-velocity curve. STATISTICAL ANALYSIS: Student t-test was used for to compare quantitative variables. ANOVA was used to test inter-group differences in categoric variables. RESULTS: In all cases, surgery-side gain on head impulse test was low, with increased gain asymmetry. A subgroup of 7 patients (18%) showed relatively high gain in vestibulo-ocular reflex on the surgery side. Caloric reaction was absent in all cases. These findings indicate that residual vestibular function can be conserved following vestibular schwannoma extirpation. CONCLUSION: Cases with moderate vestibulo-ocular reflex gain were a subgroup with partial conservation of vestibular nerve fibers. Whether this is a predictor of better functional prognosis remains to be elucidated. Higher gain correlated with less extensive surgery and sparing of the inferior vestibular nerve. Low gain correlated with complete vestibular neurectomy. This information may guide rehabilitation strategy following surgery.

Revision operations after previous stapes surgery for persisting hearing loss.

OBJECTIVES: The aim of the study was to find out the reasons of the recurrent or persisting hearing loss after previous stapes surgery indicated for otosclerosis. BACKGROUND: Revision stapes surgery is a relatively safe surgical method. Recurrent or persisting conductive hearing loss is commonly caused by prosthesis dislocation and adhesions in the oval window. Hearing loss is directly proportional to the number of previous operations. METHOD: Retrospective analysis of 48 patients after revision stapes surgery was done over a period of 4 years (2005-2008). Improvement of the hearing and the reasons of a previous surgery failure were studied. RESULTS: RESULTS were compared to the other studies. The main reason of the failed surgery was adhesions and dislocation of the prosthesis. The mean postoperative air-bone gap was 12.0 dB. A mean postoperative air-bone gap closure within 10 dB occurred in 24 cases (55.8 %), between 11-20 dB occurred in 11 cases (25.6 %) and above 20 dB in 8 cases (18.6 %). The original prosthesis was replaced with a new one in 41 (95.3 %) cases. In 2 cases (4.7 %), previous prostheses were left in place and fixed by a ionomer glass cement to the long process of incus. CONCLUSION: Revision stapes surgery is a relatively safe surgical procedure allowing to improve hearing. The number of previous stapes surgery deteriorates hearing (p < 0.05) (Tab. 4, Ref. 20).

Immunohistochemical fingerprinting of the network of seven adhesion/growth-regulatory lectins in human skin and detection of distinct tumour-associated alterations.

Glycans of natural glycoconjugates are considered as a source of biological information relevant to cell adhesion or growth. Sugar-based messages are decoded and translated into responses by endogenous lectins. This mechanism assigns a functional dimension to tumour-associated changes of glycosylation. Consequently, it calls for mapping the lectin presence in tumours. Such an analysis has so far commonly been performed with the scope to determine expression of a few distinct proteins, e.g. from the effector family of galectins with focus on galectins-1 and -3. Due to the emerging evidence for functional divergence among galectins it is timely to address the challenge to evaluate their presence beyond these few family members. Having raised a panel of non-cross- -reactive antibodies against seven human galectins covering all three subfamilies, we de scribe their expression profiles in human skin. Comparison of normal and malignant tissues enabled us to define galectin-type-dependent alterations, arguing in favour of distinct functionalities. It is concluded that comprehensive monitoring performed to define the different aspects of the galectin network, as documented in this pilot study, is advisable for future histopathologic studies aimed at delineating clinical correlations.

Phenotypic characterization of human keratinocytes in coculture reveals differential effects of fibroblasts from benign fibrous histiocytoma (dermatofibroma) as compared to cells from its malignant form and to normal fibroblasts.

BACKGROUND: Benign and malignant fibrous histiocytoma present with a considerable difference concerning cellular organization in their vicinity. OBJECTIVE: Normally appearing epithelium covers the malignant form in contrast to hyperplastic epidermis for benign tumors. It is an open question as to whether the tumor-associated fibroblasts are capable to affect phenotypic features of normal keratinocytes, prompting this comparative analysis. METHODS: Fibroblasts were isolated from benign and malignant fibrous histiocytomas, respectively, and also from normal dermis. The resulting cell populations were thoroughly characterized immunocytochemically using a large panel of antibodies. The three fibroblast preparations were cocultured with normal interfollicular keratinocytes. Their phenotype was characterized for distinct properties including differentiation and proliferation. RESULTS: Fibroblasts prepared from both tumor types were phenotypically practically identical with normal dermal fibroblasts. Their activities on keratinocytes were different. Cells prepared from benign fibrous histiocytoma were capable to effect strong expression of keratin 19 and production of a galectin-1-rich extracellular matrix. Fibroblasts isolated from malignant fibrous histiocytoma led to a phenotype very similar to that when keratinocytes were cocultured with normal dermal fibroblasts. CONCLUSION: Fibroblasts prepared from benign fibrous histiocytoma were biologically active on keratinocytes in a particular manner. Our results on fibroblast activity are suggested to be relevant for morphologic differences observed in vivo between normal epidermis and epidermis adjacent to the studied tumor types.

Galectin-7: will the lectin's activity establish clinical correlations in head and neck squamous cell and basal cell carcinomas?

The human lectin galectin-7 (Gal-7; p53-induced gene-1) has anti- and pro-malignant features in different in vitro models. We tried to clarify relation of its expression to cellular and clinical parameters in head and neck squamous and basal cell carcinomas. Using a non-cross-reactive antibody, immunohistochemical staining in squamous cell epithelia (epidermis, epithelium of oropharynx and larynx) (n = 57), squamous cell carcinomas (n = 47) and lymph node metastases (n = 25), as well as basal cell carcinomas (n = 10) were studied. This monitoring was flanked by processing to assess the level of differentiation (cytokeratins 10 and 14), proliferation (Ki67) and basal lamina formation (collagen IV). The results were correlated with clinical and pathological findings (grading, TNM-staging, extracapsular spread, angio- and lymphangioinvasion, perineural invasion, recurrence and survival). Gal-7 resides in all layers of epithelia with cytoplasmic and nuclear localization in normal specimens. Basal cell carcinomas were devoid of the Gal-7 respective signal. Squamous cell carcinomas were positive, presenting different staining profiles. Intense staining was predominantly found in squamous cell cancers with high degrees of differentiation and keratinization. Fittingly, poor level of differentiation (P = 0.0009), absence of keratinization (P = 0.0105) and significant discontinuity or absence of collagen IV expression in the peritumoral basal lamina (P = 0.0024) was found in Gal-7-negative tumors. Gal-7 presence was not related to gender, primary tumor site, T-stage, N-stage, clinical stage, extracapsular spread, angio- and lymphangioinvasion, perineural spread or treatment outcome at a statistically significant level. Immunohistochemical analysis revealed a positive correlation for differentiation and keratinization to Gal-7 presence in squamous cell carcinomas. Absence of Gal-7 expression was detected in basal cell carcinomas. These clinical data delineate Gal-7 influence on differentiation in vivo, without evidence for a role in dissemination reported for lymphoma.

[Galectins in squamous cell carcinomas of the head and neck cancers]. / Galektiny v dlazdicových karcinomech hlavy a krku.

Cancers of head and neck represents about 5% of all tumors. 80 to 90% of these tumors are constituted of squamous cell carcinomas. Despite a rapid progress in diagnostics and therapy the overall 5-year survival of this type of cancer is among the lowest of the major cancer types. This unfavourable situation needs the extensive research to found new markers to better characterize biological behavior of tumors as a rational background for more sophisticated therapeutic modalities. Among the most promising markers are endogenous lectins called galectins and their ligands. Especially galectin-1, -3 and -7 play a key role in pathology of squamous cell carcinomas.