Importance of chewing, saliva, and swallowing function in patients with advanced oral cancer undergoing preoperative chemoradiotherapy: a prospective study of quality of life.

The primary objective of this study was to investigate the quality of life (QOL) of patients with oral squamous cell carcinoma (OSCC) undergoing curative neoadjuvant chemoradiotherapy followed by radical tumour resection and simultaneous oral cavity reconstruction, using two validated questionnaires. A secondary objective was to assess clinical variables predicting post-treatment dysfunction in chewing, saliva, and swallowing. Thirty-five patients with locally advanced OSCC who underwent preoperative chemoradiotherapy were recruited prospectively. All patients completed both the University of Washington Quality of Life version 4 questionnaire (UW-QOL) and the Functional Assessment of Cancer Therapy-Head & Neck version 4 questionnaire (FACT-H&N). UW-QOL and FACT-H&N items were associated with clinical variables. Nearly three-quarters of OSCC patients perceived good to excellent levels of overall QOL after preoperative chemoradiotherapy. Chewing difficulties, decreased salivary function, and swallowing dysfunction were the most frequent complaints of OSCC patients. Items related to food intake were significantly worse in OSCC patients older than 60 years and those with T4 tumours, as well as those without alcohol intake. Chewing, saliva, and swallowing are the most significant issues in patients with OSCC undergoing preoperative chemoradiotherapy. The results of this study may help guide treatment decisions for OSCC patients based on more accurate expectations of adverse effects of cancer treatment.

RCAS-1 serum and tumor levels in head and neck squamous cell carcinoma.

BACKGROUND/AIMS: RCAS-1 is a transmembrane protein that is involved in the evasion of host immune surveillance by tumor cells. It has been found to be a valuable prognostic and diagnostic marker in a number of different malignancies. The objective of the study was to analyze the potency of RCAS-1 as a biomarker in the serum of patients with head and neck squamous cell carcinoma (HNSCC). METHODS: ELISA was performed with prospectively collected serum samples from 60 patients with HNSCC (taken at the time of diagnosis, after 3 and 12 months) and from 31 healthy controls. To correlate serum levels with RCAS-1 expression in the tumor, immunohistochemical staining of RCAS-1 was done using a tissue microarray. RESULTS: Surprisingly, median sRCAS-1 levels were basically identical between tumor patients and controls. Interestingly, patients with low RCAS-1 values at the time of diagnosis had better disease-free survival. 62% of tumor samples expressed RCAS-1 but we could not demonstrate a correlation between protein expression and serum levels. CONCLUSION: This study was the first to correlate RCAS-1 levels in the serum and in the tumor of the same patients. RCAS-1 seems to have prognostic properties although larger studies will be necessary to fully evaluate its role in HNSCC.

Strong evidence for up-regulation of cyclooxygenase-1 in head and neck cancer.

BACKGROUND: Cyclooxygenase-1, in contrast to cyclooxygenase-2, is generally reported to be constitutively expressed as a housekeeping enzyme in many different tissues. A number of recently published reports, however, challenge the notion that cyclooxygenase-1 expression is invariably constitutive by demonstrating that this enzyme might be up-regulated under certain pathological conditions in, for example, breast or ovarian cancer cells. In this study we investigated the expression of cyclooxygenase-1 in head and neck tumours and compared it to the cyclooxygenase-1 expression levels in normal oropharyngeal epithelial cells. MATERIAL AND METHODS: Paraffin-embedded pretreatment biopsies were obtained from head and neck tumour patients (n = 35). In addition, samples of normal oropharyngeal mucosa were taken from patients (n = 12) undergoing routine tonsillectomy. Cyclooxygenase-1 expression levels were determined by immunohistochemistry, Western blotting and real-time RT-PCR in cancerous tissue versus normal mucosa. RESULTS: Immunohistochemistry revealed overexpression of cyclooxygenase-1 in tumour biopsies compared to normal mucosa. Cyclooxygenase-1 was highly synthesized in the cytoplasm of neoplastic cells while significantly lower levels were detectable in normal mucosal cells. Western blotting and real-time RT-PCR also demonstrated higher cyclooxygenase-1 levels in tumour specimens compared to normal tissue samples. CONCLUSION: In this study we show for the first time that cyclooxygenase-1 is overexpressed in head and neck cancer cells compared to epithelial cells of normal mucosa.

Challenging a dogma--surgery yields superior long-term results for T1a squamous cell carcinoma of the glottic larynx compared to radiotherapy.

AIMS: The aim of this study was to compare laser surgery, conventional endoscopic surgery and radiotherapy in the treatment of early T1a glottic cancer. METHODS: We conducted a retrospective analysis of patients with early vocal cord cancer (who underwent either conventional surgery via endoscopy or laryngofissur, or primary radiotherapy) at the Medical University of Vienna. By univariate and multivariate Cox regression models the influence of treatment and other parameters on survival and locoregional control were analysed. RESULTS: 337 Patients were analyzed with a mean follow-up period of 133.8 months. Overall survival rates where similar in all three treatment groups. Five-year, 10-year and 15-year estimates of disease specific survival for laser-treated patients were 100%, for conventional surgery were 100%, 98% and 98%, and for radiotherapy were 96%, 92% and 91%, respectively. Locoregional recurrences were observed after laser surgery in 10%, after conventional surgery in 13% and after radiotherapy in 30% of the patients treated. According to the log-rank test, time to relapse was significantly shorter for irradiated patients compared to patients who underwent surgery (p < 0.0001). Mortality caused by the laryngeal tumour was significantly higher in the radiotherapy group (p = 0.003). CONCLUSION: Patients undergoing laser or conventional surgery have a significantly lower incidence of locoregional recurrences and longer disease-free intervals when compared to patients treated by radiotherapy.

Plasma concentrations might lead to overestimation of target site activity of piperacillin in patients with sepsis.

OBJECTIVES: Pharmacokinetic (PK)/pharmacodynamic (PD) models have become increasingly important in optimizing antimicrobial therapy. This approach is highly recommended by regulatory authorities intending to force the evaluation of antimicrobial action at the site of infection. METHODS: Clinical isolates of Pseudomonas aeruginosa and Staphylococcus aureus with MICs of 4, 8 and 16 mg/L for piperacillin were used in an in vivo PK/in vitro PD model. Bacteria were exposed in vitro to the concentration-versus-time profiles of piperacillin in plasma and subcutaneous adipose tissue measured in vivo in septic patients. Samples were withdrawn at defined intervals and the numbers of bacteria per mL were counted and plotted against time. RESULTS: Piperacillin levels determined in plasma were able to effectively inhibit bacterial growth of all bacterial strains used in the present study (MIC ranged from 4-16 mg/L). In contrast, concentration-versus-time profiles of subcutaneous adipose tissue were effective in killing isolates with MICs of 4 and 8 mg/L only, while bacterial growth of S. aureus and P. aeruginosa with MICs of 16 mg/L was not inhibited. CONCLUSIONS: Bacteria with MICs < 16 mg/L were effectively inhibited in subcutaneous adipose tissue in patients with sepsis. The prediction of microbiological outcome based on concentrations of piperacillin in plasma resulted in a marked overestimation of antimicrobial activity at the site of infection.

[Evidence of osteocalcin expression in osteoblast cells of mandibular origin growing on biomaterials with RT-PCR and SDS-PAGE/Western blotting]. / Nachweis der Osteokalzinexpression osteoblastärer Zellen mandibulären Ursprungs, wachsend auf Biomaterialien, mittels RT-PCR und SDS-PAGE/Western Blotting.

A new approach to addressing difficult tissue reconstructive or replacement problems in the oral cavity is to engineer new tissue by using selective cell transplantation on polymer scaffolds. The current study characterized the osteoblastic nature of adherent mandibular cells on biomaterials, which could have a potential use as scaffolds for tissue engineering strategies. Cells of mandibular origin from one patient were cultivated on three different biomaterials (PepGen P-15 trade mark, Frios Algipore, and OsteoGraf/LD-700) for 7 and 14 days and osteocalcin expression was demonstrated by RT-PCR and SDS-PAGE/Western blotting. In order to explicitly characterize only the adherent cells on the biomaterials, we first separated the biomaterials with adherent cells from the culture plate before trypsinization. We could demonstrate that cell growth of adherent mandibular osteoblast-like cells was significantly higher on biomaterials with an organic component (PepGen P-15 trade mark ) in comparison to Frios Algipore and OsteoGraf/LD-700, respectively. In conclusion, only the explicit study of adherent cells at the gene and protein levels gives information about the osteoconductivity of biomaterials.

Platinum determination by inductively coupled plasma-sector field mass spectrometry (ICP-SFMS) in different matrices relevant to human biomonitoring.

The analytical challenges of Pt determination by ICP-SFMS posed by different human tissues and fluids have been critically assessed. Investigated samples were (1) urine, (2) serum of cancer patients sampled during chemotherapy with carboplatin, (3) microdialysates (20 micro L sample volume) collected from tumor and non-tumor tissue, and, finally-for the first time-(4) human lung tissue to study background concentrations of inhaled platinum. Sample preparation involved microwave digestion and open vessel treatment or simple dilution (microdialysates). Depending on the sample preparation and introduction systems used (microconcentric nebulization, ultrasonic nebulization with and without membrane desolvation) excellent procedural detection limits (3s criterion) of 0.35 pg g(-1) for urine, 420 pg g(-1) for serum, 400 pg g(-1) for lung tissue and 13 pg g(-1) for microdialysates could be obtained. Ultratrace concentrations of 1-40 pg g(-1), and 1000-3000 pg g(-1) were measured in urine and human lung tissue, respectively, as typical for samples in environmental studies. Quantification was carried out by IDMS and standard addition in the case of urine samples. Internal standardization could not correct for non-spectral interferences in external calibration. In the serum and microdialysates of patients during chemotherapy with carboplatin, elevated Pt levels ranging between 0.01 and 10 micro g g(-1) were determined by external calibration ((195)Pt isotope). For all investigated samples spectral interferences could be excluded by following different strategies. High-resolution control measurements ((194)Pt, (195)Pt) were performed in the case of elevated Pt levels, i.e. for microdialysates and serum samples. An Hf/Pt ratio of 0.4 was determined in human lung samples. An HfO formation ratio of 0.2% was assessed for standard solutions at the present experimental conditions, revealing that the contribution of (179)Hf(16)O, (178)Hf(17)O, (177)Hf(18)O to the (195)Pt isotope signal used for quantification was not significant.

Vascular endothelial growth factor receptor 2 (VEGFR2) expression in squamous cell carcinomas of the head and neck.

OBJECTIVES: Vascular endothelial growth factor receptor 2 (VEGFR2; Flk-1 [fetal liver kinase]/KDR [kinase insert domain containing receptor]) has been identified as a high affinity receptor for vascular endothelial growth factor (VEGF) on vascular endothelium. Head and neck squamous cell carcinomas (HNSCC) have already been shown to produce substantial amounts of VEGF. VEGFR2 is supposed to play a major role in tumor-neoangiogenesis. METHODS: We investigated 24 tumor specimens and 4 HNSCC cultured tumor cell lines for the incidence and distribution of VEGFR2 by immunohistochemistry using monoclonal antibodies (mAbs) and RT-PCR. RESULTS: Analysis of frozen sections by immunohistochemistry showed that in 90% of tumor specimens VEGFR2-positive cells were found which were associated with vascular endothelium. VEGFR2 was also expressed on tumor cells and vessels, which was confirmed by double immunolabeling of tumor cells with an a-cytokeratin mAb. Furthermore, 2 (JPPA, SCC9) of 4 HNSCC cultured tumor cell lines revealed positive VEGFR2 immunoreactivity. Synthesis of VEGFR2 mRNA on all 4 HNSCC cultured tumor cell lines (JPPA, SCC9, SCC25, and LFFR) and in 6 tumor specimens was confirmed by RT-PCR. In conclusion, our results showed that VEGFR2 is expressed in HNSCCs on tumor cells. VEGFR2 expression is associated with the beginning of vasculogenesis represented by accumulation of VEGFR2-positive cells budding into new vessels ("hot spots"). The focal expression pattern of VEGFR2 on tumor cells suggests an autocrine loop for VEGF in tumor cell growth.

Distribution and antimicrobial activity of fosfomycin in the interstitial fluid of human soft tissues.

Fosfomycin is a broad-spectrum antibiotic which is established as therapy for uncomplicated lower urinary tract infections. In addition, preliminary data indicate that fosfomycin has a potential role in the treatment of soft tissue infections. However, the use of fosfomycin has not been established for this condition, and it is unclear whether the level of fosfomycin penetration into human soft tissues is high enough to eradicate relevant pathogens. To better characterize the antibiotic potential of fosfomycin, we applied a combined in vivo pharmacokinetic-in vitro pharmacodynamic model to human volunteers. For this purpose fosfomycin concentrations in vivo in the fluid of the interstitial space of human soft tissues were measured by microdialysis following intravenous infusion of 4 or 8 g of fosfomycin (n = 6). Subsequently, bacterial isolates with relevance for soft tissue infections were exposed to concentrations according to the in vivo pharmacokinetic profile in the interstitial space fluid obtained by microdialysis. Our experiments indicated a high degree of soft tissue penetration for fosfomycin, with ratios of the area under the concentration-time curve from 0 to 8 h for muscle (AUC(0-8(muscle)))/AUC(0-8(serum)) of 0.48+/-0.08 and 0.53+/-0.04 and ratios of AUC(0-8(adipose tissue))/AUC(0-8(serum)) of 0.74+/-0.12 and 0.71+/-0.11 following administration of 4 and 8 g, respectively. In corresponding in vitro simulation experiments with selected isolates of Staphylococcus aureus, Enterobacter cloacae, and Serratia marcescens for which MICs were 16 microg/ml, organisms were undetectable after a single dosing interval. Fosfomycin exhibits a strong ability to penetrate into the fluid of the interstitial space of soft tissues and reaches levels sufficient to substantially inhibit the growth of relevant bacteria at the target site. We therefore conclude that fosfomycin might qualify as an alternative candidate for the therapy of soft tissue infections.

Validation of urea as an endogenous reference compound for the in vivo calibration of microdialysis probes.

Microdialysis is a widely used experimental technique, which offers the opportunity to measure drug and metabolite concentrations in the interstitial space fluid in animals and humans. However, microdialysis probes need to be calibrated in vivo to obtain a recovery factor, which describes the relative drug transfer across the membrane. Recently, novel time-saving calibration techniques, based on the use of reference compounds, have been developed. In particular, the use of endogenous urea levels has been advocated. In the present study we set out to validate the use of the urea reference technique for microdialysis probe calibration in healthy volunteers, employing glucose and paracetamol as model analytes. Urea calibration was compared with the results of two standard calibration techniques, i.e. the no net flux technique and the retrodialysis technique. For glucose, recovery values, calculated by the urea reference technique differed significantly from those values, which were assessed by the no net flux technique (p < 0.05), whereas for paracetamol recovery values did not differ significantly, albeit a high intramethod variability was observed (CV=66%). As a conclusion, we could not confirm the hypothesis that recovery values calculated by the urea reference technique provide equivalent results compared with standard calibration techniques.

Target site concentrations after continuous infusion and bolus injection of cefpirome to healthy volunteers.

BACKGROUND: Recent data indicate a higher level of effectivity of beta-lactam antibiotics if serum concentrations are kept above the minimal inhibitory concentration (MIC) of the pathogen. This concept would favor continuous infusion over bolus dosing. However, it is usually not the serum concentration but the free interstitial concentration in the target tissue that determines antibiotic activity. We therefore set out to measure effective drug concentrations in the interstitial space of muscle and subcutaneous adipose tissue and to compare trough levels and times above the MIC after bolus versus continuous infusion of cefpirome. METHODS: Twelve healthy volunteers received a single dose of 2 g cefpirome as an intravenous bolus or as a continuous infusion over 8 hours in a crossover design, and the resulting free interstitial tissue concentrations were measured with use of microdialysis. RESULTS: After bolus injection, mean interstitial trough concentrations were 3.0 +/- 1.9 microg/mL and 2.1 +/-1.0 microg/mL for muscle and subcutaneous tissue, respectively; continuous infusion resulted in trough levels of 10.1 +/- 6.8 microg/mL and 10.1 +/- 4.6 microg/mL for muscle and subcutaneous tissue, respectively. This resulted in significantly longer times above the MIC with continuous infusion for Staphylococcus epidermidis and Enterobacter cloacae. Bacteria with an MIC < or =1 would be covered by either method, whereas higher doses seem to be necessary for Pseudomonas aeruginosa. CONCLUSION: Although susceptible organisms will usually be covered sufficiently with standard dosing regimens, soft tissue infections with bacteria that have MIC values of 2 to 8 may profit from continuous application. Coverage of P aeruginosa, however, would be inadequate with conventional daily doses of 4 g cefpirome regardless of the method of application.