CD31 and VEGF are prognostic biomarkers in early-stage, but not in late-stage, laryngeal squamous cell carcinoma.

BACKGROUND: Patients suffering from squamous cell carcinoma of the larynx (LSCC) with lymphatic metastasis have a relatively poor prognosis and often require radical therapeutic management. The mechanisms which drive metastasis to the lymph nodes are largely unknown but may be promoted by a pro-angiogenic tumor microenvironment. In this study, we examined whether the number of microvessels and the expression level of vascular endothelial growth factor (VEGF) in the primary tumor are correlated with the degree of lymph node metastasis (N-stage), tumor staging (T) and survival time in LSCC patients. METHODS: Tissue-Microarrays of 97 LSCC patients were analyzed using immunohistochemistry. The expression of VEGF was scored as intensity of staining (low vs high) and the number of CD31-positive vessels (median

Comparative analysis of resection tools suited for transoral robot-assisted surgery.

Introduction of transoral robot-assisted surgery (TORS) has a strong potential to facilitate surgical therapy of head and neck squamous cell cancer (HNSCC) by decreasing the indication for an external surgical approach. However, the availability of resection tools is limited and comparative studies in the context of TORS are not available. In the context of the newest da Vinci Si HD(®) robotic system, various dissection methods were compared in a surgical animal model using porcine tongue at three different sites representing mucosal, muscular and lymphatic tissue. Resection methods included (a) CO2 laser tube, (b) flexible fiber Tm:YAG laser, (c) monopolar blade, and (d) radio frequency (RF) needle. Specimens were formalin-fixed, paraffin-embedded, cut, and stained with haematoxylin-eosin. Dissected tissue was examined for the width of the incision as well as the individual coagulation zone of each tool at various tissue sites. In addition, instrument costs and performance were determined. The incisions made by the RF needle had the most favourable cutting width and also smaller coagulation defects, as opposed to other tools, granting the best preservation of tumour-adjacent structures and improved pathological assessment. Instrument performance was best evaluated for CO2 laser and RF needle, whereas financial expenses were lowest for RF needle and monopolar blade. Improvement and modification of resection tools for TORS become a relevant criterion in order to facilitate routine usage in the surgical therapy of HNSCC. A consequent decrease in surgical mortality and improved precision of surgical tumour resection could lead to a significant clinical growth potential of TORS.

Gentamicin alters nitric oxide production in semicircular canals and otolith organs.

OBJECTIVES/HYPOTHESIS: Intratympanic application of gentamicin is an important therapeutic option to control vertigo spells in Ménière's disease. Low doses eliminate the function of semicircular canal ampullae (SCCA) and saccule in most patients, although utricular function is maintained in many cases. Local alteration in free radical production might be responsible for these differences. Therefore, the gentamicin-induced nitric oxide (NO) production was determined in an animal model using separate organ cultures of SCCA, saccule, and utricle. STUDY DESIGN: Prospective pilot study in male guinea pigs. METHODS: SCCA, saccule, and utricle of 28 guinea pigs were isolated and incubated separately for 6 hours in cell culture medium. Gentamicin was administered in two different concentrations (0.4 mg/mL and 0.8 mg/mL) to organ cultures of 16 animals. Tissues from 12 animals were used as controls. Nitric oxide was quantified by chemiluminescence. RESULTS: Gentamicin led to an NO increase of about 70% in the saccule, an NO reduction of more than 70% in SCCA, and an NO reduction of 36% in the utricle. CONCLUSIONS: The selective effects of gentamicin on the NO production in the different sensory areas of the vestibular organ have to be taken into account in the therapy of Ménière's disease.