The Etiology and Pathogenesis of Laryngeal Carcinoma

Targeting laryngeal cancer cells with 5-fluorouracil and curcumin using mesoporous silica nanoparticles

Objective:

To explore the inhibitory and synergistic effects of 5-fluorouracil and curcumin on Hep-2 laryngeal cancer cells and clarify the effect of mesoporous silica nanoparticles as drug carriers.

Methods:

The inhibitory effects of 5-fluorouracil and curcumin on Hep-2 cells were detected using the CCK-8 assay. CompuSyn was used to calculate the synergistic effect of the 2 drugs. Flow cytometry was used to detect apoptosis and cell cycle arrest induced by 5-fluorouracil and curcumin. The drugs were loaded into mesoporous nanoparticles. Western blotting was used to detect the expression of related proteins after treatment. The growth of subcutaneous tumors in BALB/c nude after the intraperitoneal injection with drug-loaded mesoporous silica nanoparticles was recorded.

Results:

5-Fluorouracil and curcumin synergistically induced apoptosis and cell cycle arrest in Hep-2 cells. Mesoporous silica nanoparticles as drug carriers enhanced the therapeutic effects of 5-fluorouracil and curcumin.

Conclusions:

Mesoporous silica nanoparticles are expected to be effective drug carriers that enhance the synergistic effects of 5-fluorouracil and curcumin on laryngeal cancer.

Analysis of reflux as the aetiology of laryngeal dysplasia progression through a matched case-control study

OBJECTIVES

Laryngeal dysplasia (LD) is a precancerous lesion of the larynx. In this study, the laryngeal tissue of patients with laryngeal dysplasia was taken as the research object, and the aetiology of reflux was analysed.

METHOD

Patients with laryngeal dysplasia after surgery were selected as our subjects. The levels of pepsin, enterokinase and bilirubin in laryngeal tissue samples of the two groups were detected by immunohistochemical method.

RESULTS

The OR values (95% CI) of pepsin, enterokinase and bilirubin were 0.67 (0.19-2.36), 0.80 (0.22-2.98) and 1.33 (0.30-5.96), respectively, in the univariate analysis. Besides, in the multivariate analysis, the OR values (95% CI) of pepsin, enterokinase and bilirubin were 0.57 (0.14-2.30), 0.73 (0.18-2.92) and 1.40 (0.30-6.53), respectively.

CONCLUSION

Larger sample size should be applied to prospective studies on whether reflux is a risk factor for laryngeal cancer.

Reflux Esophagitis as a Possible Risk Factor in the Development of Pharyngolaryngeal Squamous Cell Carcinoma

Aims and background

To determine the role of reflux esophagitis in the development of pharyngolaryngeal squamous cell carcinoma in non-smoking and non-drinking patients.

Methods

The study population consisted of 92 consecutive non-smoking and non-drinking patients with histologically confirmed squamous cell carcinoma of the pharynx and the larynx. As a control, a group of 125 lifetime non-smoking and non-drinking cancer-free subjects was selected.

Results

Patients with pharyngolaryngeal cancer had a higher prevalence of reflux esophagitis than the control subjects (P <0.0001).

Conclusions

Our results confirm that reflux esophagitis in itself is associated with an increased risk of upper aerodigestive tract cancer.

Gastro-pharyngeal reflux and total laryngectomy. Increasing knowledge about its management

PURPOSE

Investigate the incidence, the degree and the effect of gastro-pharyngeal reflux (GPR) in laryngectomised patients.

MATERIALS AND METHODS

Behavioral and 24-hour pH- and impedance-monitoring data were prospectively analyzed for 25 laryngectomised patients with no previous history of GER in outpateints' setting. Reflux detected was characterized as either acid, weakly acidic or nonacid. Proximal reflux was found at 15cm above the LES.

RESULTS

40% of patients presented a pathological number of reflux episodes in the upright position (p<0.0001); 9 of them presented a pathologic bolus exposure time. Bolus exposure at the proximal sphincter was one fourth-fold lower than 5cm above the LES (p=0.3593). There was a prevalence of acid reflux at both sphincters (p<0.0001); liquid reflux was prevalent at the LES (p=0.003) and mixed reflux at the UES (p=0.0001). Median REs was higher than time acid exposure (p=0.0013).

CONCLUSIONS

Pre- and post-surgical reflux investigation could identify preexisting reflux severity and screen potential high-risk cancer patients for postoperative complications. This might allow the early onset of acid suppressive therapy in presence of pathologic findings in high-complication risk cancer patients.

TSR2 Induces laryngeal cancer cell apoptosis through inhibiting NF-κB signaling pathway

OBJECTIVES/HYPOTHESIS

Human laryngeal squamous cell carcinoma (LSCC) is a malignancy that was discovered originally in the epithelial tissue of laryngeal mucosa. However, the underlying molecular mechanism is still not clear. In this study, we aimed to investigate the potential molecular mechanisms of TSR2 in the LSCC cell apoptosis.

STUDY DESIGN

The expression of TSR2 was first analyzed in LSCC tissues. Then functional effects of TSR2 on Hep-2 and AMC-HN-8 cell lines were performed by overexpression pcDNA3.1-TSR2.

METHODS

We investigated the expression level of TSR2 in LSCC tissues and cells by performing quantitative real-time polymerase chain reaction (qRT-PCR). The pcDNA3.1-TSR2 was constructed to explore the effect of overexpressing TSR2 in Hep-2 cells and AMC-HN-8 cells. We further investigated the effect of overexpressing TSR2 on cell apoptosis-related protein and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) p65 nuclear translocation through Western blot and terminal dUTP nick end-labeling assays.

RESULTS

We found that TSR2 was downregulated in LSSC tissues and cells compared with the controls, and the overexpression of TSR2 in Hep-2 and AMC-HN-8 cells could promote cell apoptosis and related apoptosis proteins. The Western blot/qRT-PCR data further indicated that overexpression of TSR2 in Hep-2 and AMC-HN-8 cells could lead to a block of NF-κB signaling pathway via decreasing nuclear NF-κB p65 and increasing cytoplasm NF-κB p65. Moreover, overexpression of TSR2 significantly inhibited the phosphorylation of IκBα and IKKα/β.

CONCLUSIONS

The results indicated that TSR2-induced apoptosis was mediated by inhibiting the NF-κB signaling pathway, which may provide an effective target in gene therapy for LSCC.

LEVEL OF EVIDENCE

NA. Laryngoscope, 128:E130-E134, 2018.

Elevated Serum CD95/FAS and HIF-1α Levels, but Not Tie-2 Levels, May Be Biomarkers in Patients With Severe Endometriosis: A Preliminary Report

STUDY OBJECTIVE

To evaluate serum values of cluster of differentiation 95 (CD95/FAS), hypoxia-inducible factor 1-alpha (HIF-1α), and tyrosine kinase receptor 2 (Tie-2) as possible biomarkers of disease presence and severity in women with endometriosis, and to characterize the changes in these values in women with stage I/II and stage III/IV endometriosis.

DESIGN

Prospective study (Canadian Task Force classification I).

SETTING

University hospital.

PATIENTS

Thirty women with endometriosis and 30 healthy women without endometriosis.

INTERVENTION

For the diagnosis of endometriosis and prediction of its severity, we measured the serum levels of CD95/FAS, which assess apoptotic conditions, and of HIF-1α and Tie-2, which assess angiogenesis. Endometriosis was diagnosed and staged through surgical laparoscopy and later confirmed histologically. During the surgery, the patients with endometriosis were divided into 2 groups based on disease stage. Eleven patients had stage I/II endometriosis, and 19 had stage III/IV endometriosis.

MEASUREMENTS AND MAIN RESULTS

Endometriosis was associated with increased serum CD95/FAS and HIF-1α levels, but not Tie-2 levels. We also determined that stage III/IV endometriosis was associated with higher serum CD95/FAS and HIF-1α levels, but not Tie-2 levels, compared with stage I/II endometriosis.

CONCLUSION

Endometriosis, in accordance with its severity, increases serum CD95/FAS and HIF-1α levels, but not Tie-2 levels. These biomarkers may be useful for reproductive surgeons to improve the quality of counseling women about the presence and severity of endometriosis.

Estimation of the efficacy of chemo-radiotherapy on tumor regression in the patients with laryngeal cancer via computerized tomography using the Cavalieri method

CONCLUSION

Calculating tumor volume using the Cavalieri method in laryngeal tumors before and after treatment may be useful to optimize the treatment and to minimize the side-effects of radiotherapy.

PURPOSE

This study aimed to estimate the pre-treatment and post-treatment tumor volumes of the patients to whom radiotherapy or radio-chemotherapy was applied as a treatment using Cavalieri's Principle as a stereological method and to assess tumor regression rates in the patients with Laryngeal Squamous Cell Carcinoma (LSCC) statistically.

MATERIALS AND METHOD

Sixteen patients (eight patients with stage T3 and eight patients with stage T4) diagnosed with LCCC bearing the appropriate characteristics to criteria in the otorhinolaryngology clinic were included. Patients had computerized tomography (CT) scans in the axial plane before treatment and 2 months after the treatment. Pre-treatment and post-treatment tumor volumes on CT images were calculated using Cavalieri's principle as a stereological method and then compared.

FINDINGS

Average tumor volumes in patients with stage T3 before and after treatment were 10.12 ± 3.58 cm(3) and 1.33 ± 1.74 cm(3), respectively (p = 0.008). These volumes were 11.92 ± 4.61 cm(3) and 2.17 ± 2.34 cm(3) (p = 0.008) for patients with stage T4, respectively. Post-treatment tumor volumes were statistically reduced compared to pre-treatment volumes in all stages.

Association between helicobacter pylori infection and carcinoma of the larynx or pharynx

BACKGROUND

Infection with Helicobacter pylori (H. pylori) plays a role in the development of gastric carcinoma. However, there is controversy as to whether H. pylori infection increases laryngeal or pharyngeal cancers.

METHODS

We managed a systematic review of researches related to H. pylori infection in laryngeal or pharyngeal carcinomas, distributed up to December 2014. Odds ratios (ORs) and 95% confidence intervals (CIs) were assessed by random effects models or according to heterogeneity I(2) .

RESULTS

Eleven studies were involved in the meta-analysis. Overall, H. pylori infection was significantly higher in the study group compared with the normal control group (OR = 2.87; 95% CI = 1.71-4.84; I(2) = 67.1; p < .0001, random effects analysis). The ORs for laryngeal carcinoma were 3.28 (95% CI = 1.91-5.63; I(2) = 58; p < .0001, random effects model). The ORs for pharyngeal cancer were 1.35 (95% CI = 0.86-2.12; p = .188, random effects model).

CONCLUSION

This study supported the proposition that infection with H. pylori was related to laryngeal carcinoma, specifically in the hospital-based control group and diagnosed by polymerase chain reaction (PCR) or enzyme-linked immunosorbent assay (ELISA). Nevertheless, no significant relationship was discovered between H. pylori infection and pharyngeal cancer. © 2015 Wiley Periodicals, Inc. Head Neck 38: E2291-E2296, 2016.

Gene and miRNA expression changes in squamous cell carcinoma of larynx and hypopharynx

Laryngo-pharyngeal squamous cell carcinomas are one of the most common head and neck cancers. Despite the presence of a large body of information, molecular biomarkers are not currently used in the diagnosis, treatment and management of patients for this group of cancer. Here, we have profiled expression of genes and microRNAs of larynx and hypopharynx tumors using high-throughput sequencing experiments. We found that matrix metalloproteinases along with SCEL, CRNN, KRT4, SPINK5, and TGM3 among others have significantly altered expression in these tumors. Alongside gene expression, the microRNAs hsa-miR-139, hsa-miR-203 and the hsa-miR-424/503 cluster have aberrant expression in these cancers. Using target genes for these microRNAs, we found the involvement of pathways linked to cell cycle, p53 signaling, and viral carcinogenesis significant (P-values 10(-13), 10(-9) and 10(-7) respectively). Finally, using an ensemble machine-learning tool, we discovered a unique 8-gene signature for this group of cancers that differentiates the group from the other tumor subsites of head and neck region. We investigated the role of promoter methylation in one of these genes, WIF1, and found no correlation between DNA methylation and down-regulation of WIF1. We validated our findings of gene expression, 8-gene signature and promoter methylation using q-PCR, data from TCGA and q-MSP respectively. Data presented in this manuscript has been submitted to the NCBI Geo database with the accession number GSE67994.

MicroRNA-24 inhibits growth, induces apoptosis, and reverses radioresistance in laryngeal squamous cell carcinoma by targeting X-linked inhibitor of apoptosis protein

Background

Increasing evidence indicates that dysregulation of microRNAs is involved in tumor progression and development. The aim of this study was to investigate the expression of microRNA-24 (miR-24) and its function in laryngeal squamous cell carcinoma (LSCC).

Methods

Quantitative RT-PCR (qRT-PCR) was used to detect miR-24 expression in LSCC cell lines and tissue samples. MTT, colony formation, and flow cytometry was performed to analyze the effects of miR-24 expression on growth, apoptosis, and radiosensitivity of LSCC cells. Dual-luciferase reporter assays were performed to examine regulation of putative miR-24 targets. Expression of X-linked inhibitor of apoptosis protein (XIAP) mRNA and protein, cleaved or total caspase-3, and cleaved or total PARP protein were detected by qRT-PCR and western blotting assays, respectively.

Results

miR-24 expression levels in LSCC cell lines or tissue were significantly lower than in a normal human keratinocyte cell line or adjacent normal tissues. Functional analyses indicated that re-expression of miR-24 inhibits growth, reduces colony formation, and enhances apoptosis in LSCC cells. In addition, miR-24 upregulation increases LSCC sensitivity to irradiation by enhancing irradiation-induced apoptosis, and luciferase activity indicated that miR-24 binds to the 3′-untranslated region (3′-UTR) of XIAP mRNA. Upregulation of miR-24 inhibits XIAP protein expression in LSCC cells, and silencing of XIAP mimics the effects of miR-24 upregulation on LSCC cells. In addition, XIAP mRNA expression significantly increases in LSCC tissues and is inversely correlated with miR-24 expression.

Conclusions

Our data suggest that miR-24 inhibits growth, increases apoptosis, and enhances radiosensitivity in LSCC cells by targeting XIAP. Therefore, miR-24 may be a potential molecular target for the treatment of human LSCC.

Association of the Cylin D1 G870A polymorphism with laryngeal cancer: are they really related?

BACKGROUND

Cylin D1(CCDN1) is an important regulator of the cell cycle whose alterations are thought to be involved in cancer development. There have been many studies indicating CCDN1 amplification or over- expression in a variety of cancer types. In addition to gene amplification, the G870A polymorphism may be related with altered CCDN1 activity, and therefore with cancer development. This hypothesis has been tested in different cancer types but results have been contradictory. We therefore aimed to investigate any relationship between CCDN1 A870G genotypes and laryngeal squamous cell cancer development and progression.

MATERIALS AND METHODS

A total of 68 Turkish patients with primary laryngeal squamous cell cancer and 133 healthy controls were enrolled. Polymerase chain reaction-restriction fragment length polymorphism analysis was used to determine the CCDN1 genotypes.

RESULTS

No significant association was detected between CCDN1 genotypes and laryngeal squamous cell cancer (LxSCCa) development. Similarly CCDN1 genotypes were not related to clinical parameters of Lx SCCa. However, there was a very significant association between CCDN1 G allele and presence of perineural invasion (p= 0.003; OR: 1.464; CI% 1.073-1.999). CCDN1 G allele frequency was significantly higher in the individuals with perineural invasion (85.7%) when compared to those without (58.5%). The 2 patients who died of disease were both found to possess the GG genotype.

CONCLUSIONS

These results pose a controversy in suggesting a protective role of the G allele against LxSCCa development and support the association of CCDN1 gene GG genotype with mortality in patients with LxSCCa.

The role of H. pylori in the development of laryngeal squamous cell carcinoma

Aim. This study aims to investigate the possible role of H. pylori as a cause of laryngeal squamous cell carcinoma. Method. This controlled study was performed with 31 consecutive laryngeal cancer and 28 cancer-free patients who underwent direct laryngoscopy and biopsy of laryngeal lesions. To document the previous H. pylori infection, serological analysis of the antibody titers was done. Immunohistochemical analyses were applied to the tissue samples. Results. Serology was found positive at the 90.3% of the laryngeal cancer patients and 96.4% of the benign group. There were no statistically significant differences between the two groups (P > 0.05). Immunohistochemical analysis results were determined as negative at all of the specimens of laryngeal cancer patients and patients with benign lesions. Conclusion. There were no signs of colonization of H. pylori in laryngeal tissues of both groups' patients. It is thought that no relationship exists between the H. pylori infection and laryngeal squamous cell carcinoma.

New concepts in vocal fold imaging: a review

OBJECTIVE

To review new imaging technology potentially useful in the clinical practice of laryngology.

HYPOTHESIS

Narrow band imaging, iScan (Pentax Medical Company, Montvale, NJ), optical computed tomography, and confocal microscopy have potential value for enhancing diagnosis of laryngeal pathology.

DESIGN

Literature review.

METHODS

Literature search of computer databases including MEDLINE and PubMed.

RESULTS

A review of 50 articles suggests that new imaging technologies may enhance clinical diagnostic capabilities.

CONCLUSION

The probable value of new imaging technologies suggests that further research is needed to refine these technologies and define their clinical efficacy.

Part II. Mitochondrial mutational status of high nitric oxide adapted cell line BT-20 (BT-20-HNO) as it relates to human primary breast tumors

Mitochondria combine hydrogen and oxygen to produce heat and adenosine triphosphate (ATP). As a toxic by-product of oxidative phosphorylation (OXPHOS), mitochondria generate reactive oxygen species (ROS). These free radicals may cause damage to mitochondrial DNA (mtDNA) and other molecules in the cell. Nitric oxide (NO) plays an important role in the biology of human cancers, including breast cancer; however, it is still unclear how NO might affect the mitochondrial genome. The aim of the current study is to determine the role of mtDNA in the breast oncogenic process. Using DNA sequencing, we studied one breast cancer cell line as a model system to investigate the effects of oxidative stress. The BT-20 cell line was fully adapted to increasing concentrations of the NO donor DETA-NONOate and is referred to as BT-20-HNO, a high NO (HNO) cell line. The HNO cell line is biologically different from the "parent" cell line from which it originated. Moreover, we investigated 71 breast cancer biopsies and the corresponding noncancerous breast tissues. The free radical NO was able to generate somatic mtDNA mutations in the BT-20-HNO cell line that were missing in the BT-20 parent cell line. We identified two somatic mutations, A4767G and G13481A, which changed the amino acid residues. Another two point mutations were identified in the mtDNA initiation replication site at nucleotide 57 and at the 'hot spot' cytidine-rich D300-310 segment. Furthermore, the NO regulated the mtDNA copy number and selected different mtDNA populations by clonal expansion. Interestingly, we identified eight somatic mutations in the coding regions of mtDNAs of eight breast cancer patients (8/71, 11.2 %). All of these somatic mutations changed amino acid residues in the highly conserved regions of mtDNA which potentially leads to mitochondrial dysfunctions. The other two somatic mtDNA mutations in the displacement loop (D-loop) region [303:315 C(7-8)TC(6) and nucleotide 57] were distributed among 14 patients (14/71, 19.7 %). Importantly, of these 14 patients, six had mutations in the p53 gene. These results validate the BT-20 parent/HNO cell line model system as a means to study ROS damage in mtDNA, as it parallels the results found in a subset of the patient population.

Experimental model of smoking and simulation of reflux with acid and pepsin in rats

PURPOSE: To develop experimental models to evaluate the effects of hydrochloric acid associated with the pepsin instilled in the mucosa of the upper esophagus and the esophagogastric junction of young male rats Wistar, simulating injury caused by gastroesophageal reflux on the mucosa of aero-digestive tract in humans as well as the action of the risk exposure of mucosa to cigarette smoke. METHODS: Fifty young male Wistar rats divided in 5 groups with 10 animals each one, respectively simulating pharyngo-laryngeal reflux and gastroesophageal reflux, pharyngo-laryngeal reflux and smoking, smoking only, gastroesophageal reflux and control group. RESULTS: The histopathologic studies no recorded neoplasias, only mild changes and no significant alterations. The hemo-oximetry (carboxyhemoglobin and methemoglobim) and CO2 concentration confirm that the animals were submitted to high intensity of exposure to carcinogens in tobacco and its derivatives. CONCLUSION: The experimental models were highly efficient, practical, easy to use and economical and can be employed in other similar studies to determine the harmful effects by smoking and reflux.

Chemiluminescence assay of reactive oxygen species in laryngeal cancer

OBJECTIVE

This study aimed to evaluate the presence of reactive oxygen species in laryngeal cancer tissue, using a luminol-amplified chemiluminescence method.

MATERIALS AND METHODS

Fourteen patients with histopathologically diagnosed laryngeal squamous cell carcinoma were enrolled. Patients with recurrent tumours or a history of prior chemotherapy or radiotherapy were excluded. Tissue specimens were harvested both from the tumour itself and from the neighbouring, apparently normal mucosa (immediately after tumour removal). Tissue specimens were washed with ice-cold saline solution and processed immediately, without storage. The level of reactive oxygen species was measured quantitatively by a luminol-amplified chemiluminescence method.

RESULTS

The mean luminol-amplified chemiluminescence values for tumour and control tissue were 140.52 (standard error of the mean 40.21) and 121.36 (standard error of the mean 35.33) relative light units/mg tissue, respectively. Furthermore, mean tumour and control luminol chemiluminescence values were compared for stage one and two tumours versus stage three and four tumours. Both the tumour and the control luminol chemiluminescence values for the latter tumour group were significantly higher than those for the former tumour group.

CONCLUSION

This study measured directly the levels of reactive oxygen species in samples of laryngeal cancer tissue and normal mucosa. Higher levels of reactive oxygen species were found in laryngeal cancer tissue, suggesting a relationship between reactive oxygen species and laryngeal cancer.

Should inspection of the laryngopharyngeal area be part of routine upper gastrointestinal endoscopy? A prospective study

BACKGROUND

Examination of the laryngopharyngeal area is not always performed during routine upper gastrointestinal (UGI) endoscopy although initial studies reported pathological findings in 0.9-3.5% of cases. The aim of this study was to prospectively evaluate the accuracy of screening the laryngopharyngeal area during routine UGI endoscopy, before insertion of endoscope into the oesophagus, to avoid a misinterpretation of trauma-related hyperaemia or erythema as signs of laryngitis.

METHODS

The study included 1297 patients undergoing elective UGI endoscopy, asymptomatic in the laryngopharyngeal area, who underwent a carefully structured examination of the laryngopharyngeal area, videotaped for later blinded review. If pathological findings were suspected, patients were referred to otorhinolaryngologists for additional evaluation. In all cases the DVDs were reviewed by two ear, nose, and throat (ENT) specialists blinded to the endoscopic findings.

RESULTS

In 1130 (87.12%) patients the examination was performed successfully before insertion of the endoscope into the oesophagus. Gastro-oesophageal reflux disease (GORD) symptoms were present in 254 (22.5%) patients, and erosive oesophagitis was documented in 89 (7.9%) patients. In 44 (3.89%) patients the pathology was suspected by the endoscopist and confirmed by the otorhinolaryngologists. Moreover, 8 (0.71%) patients were found to have laryngeal pathology in the DVDs reviewed by the ENT specialists, further confirmed by laryngoscopy. Sensitivity, specificity, positive, and negative predictive values were 84.61%, 100%, 100%, and 99.26%, respectively, for detecting laryngeal abnormalities by the endoscopist. The most important findings were leukoplakia (n=4), posterior laryngitis (n=16), Reinke's oedema (n=2), and hyperkeratosis of arytenoid folds (n=2). A strict correlation emerged between GORD and posterior laryngitis (75%) and between GORD and Reinke's oedema (100%), documented by pHmetry. A significant association was also observed between heavy smoking and leukoplakia (75%), and hypertrophy of pharyngeal tonsils (100%), respectively. All other findings were lesions without clinical significance.

CONCLUSIONS

Screening examination of the laryngopharyngeal area should be part of each UGI endoscopy revealing important laryngeal pathology.

Experimental carcinogenesis on the oropharyngeal mucosa of rats with hydrochloric acid, sodium nitrate and pepsin

PURPOSE: To investigate the carcinogenic action of hydrochloric acid, pepsin and sodium nitrate on the oropharyngeal mucosa of rats, simulating the reflux of gastric contents. METHODS: Eighty-two Wistar rats were divided in seven groups and submitted to 2 or 3 weekly applications of hydrochloric acid, pepsin and sodium nitrate on the pharyngeal mucosa during six months. Study groups comprised 12 animals each. Rats in groups I and II were submitted to 2 (GI) or 3 (GII) weekly applications of 0.1N hydrochloric acid. Groups III and IV were submitted to 2 (GIII) or 3 (GIV) weekly applications of 0.1N hydrochloric acid solution with pepsin. Groups V and VI were submitted to 2 (GV) or 3 (GVI) weekly applications of 0.1N hydrochloric acid and treated with daily nitrate diluted in water. Group VII consisted of 10 animals submitted to 2 weekly applications of filtered water. RESULTS: No dysplasia, intra-epithelial neoplasia or invasive carcinomas were detected. Inflammatory changes were observed in varying degrees and mast cells were more common in Groups V and VI (p=0.006). CONCLUSION: The data of the current study could not corroborate the hypothesis that gastroesophageal and pharyngolaryngeal refluxes are carcinogenic factors to the laryngopharyngeal mucosa, and more studies are necessary in the future.

Laryngopharyngeal reflux: the value of otolaryngology examination

Laryngopharyngeal reflux (LPR) is the disease process by which gastric contents affect the extraesophageal structures of the head and neck. The symptoms of LPR include intermittent dysphonia, excessive throat clearing, globus pharyngeus, cough, and dysphagia. These symptoms can be assessed with the Reflux Symptom Index. Signs of LPR, as determined with laryngoscopy, can be described with the Reflux Findings Score, which includes assessment of site-specific laryngeal edema and other inflammatory changes. This article discusses the current understanding of LPR pathophysiology, taking into account pepsin stability and reactivation.

Diagnostic and management problems of laryngopharyngeal reflux disease in children

OBJECTIVE

Reflux is a common pediatric disorder and an association between reflux and otolaryngological conditions has been described. However, to prove a causal relationship a pathophysiological pathway must be identified, diagnostic test with high specificity and sensitivity must be developed and conservative or surgical treatment of reflux should be shown to predictably improve the otolaryngological problems. This review study aims at examining the available evidence for the above controversial issues.

METHODS

Articles on pediatric laryngopharyngeal reflux published in English during the last decade were searched using Ovid and PubMed.

RESULTS

A lack of consensus was found in four separate but interdependent areas: clinical manifestations, diagnostic testing, interpretation of findings and treatment. Although clinical experience and uncontrolled case series suggest that laryngopharyngeal reflux may possibly contribute to apnea, recurrent upper respiratory infections, laryngeal symptoms (mainly laryngomalacia and subglottic stenosis), sinusitis and otitis convincing data are lacking. For pediatric studies, the diagnostic role of pH monitoring, barium esophagram, scintigraphy, impedance monitoring, laryngoscopic examination, laryngeal biopsy and symptom assessment questionnaires remain to be defined. Interpretation of pharyngeal reflux events is controversial and the lack of established normative values as well as the existing variability in the diagnostic criteria (reflux definition, duration and number of pathological reflux events) limits the ability to directly compare results. Proposed laryngopharyngeal reflux treatment (lifestyle modification, medical or surgical therapy) is mostly empiric, with no significant placebo-controlled trials of treatment and outcomes.

CONCLUSIONS

Limited evidence exists to support a causative relationship between reflux and any otorhinolaryngological condition or the effectiveness of treatment. Epidemiological and large-scale prospective controlled studies are required to clarify these issues.

Molecular predictors of clinical outcome in patients with head and neck squamous cell carcinoma

Head and neck squamous cell carcinoma (HNSCC) involves the upper aerodigestive tract and can destroy the structure and function of organs involved in voice, speech, taste, smell and hearing, as well as vital structures necessary for survival. HNSCC has long been a treatment challenge because of the high rate of recurrences and of advanced disease at the time of diagnosis. Molecular identification of tissue biomarkers in diagnostic biopsy specimens may not only identify patients at risk for developing HNSCC but may also select patients that may benefit from more aggressive treatment modalities. Several biomarkers studied to date such as the proteins p53, cyclin D1, p16, Cox-2 enzyme, epidermal growth factor and vascular endothelial growth factor receptors, matrix metalloproteinases and the Fhit marker for genomic instability could be manipulated for the therapeutic benefit of these patients. This review presents the most updated information on molecular biomarkers with the greatest prognostic potential in HNSCC and discusses some factors that contribute to the controversy concerning their prognostic importance.

Extraesophageal reflux and upper aerodigestive tract diseases

Reflux disease can cause multiple disorders not only of the esophagus but also of the upper aerodigestive tract. In the last decade, an association between reflux disease and multiple head and neck diseases was described, including those of the larynx and pharynx as well as those of the nose, the sinuses and the middle ear. The present article summarizes these different diseases and possible pathomechanisms are explained. In particular, there is a need to differentiate between the classical gastroesophageal reflux disease (GERD) and the extraesophageal manifestation of the reflux disease, called extraesophageal reflux (EER). Both diseases are characterized by different symptoms and can cause different disorders. To differentiate between GERD and EER, double-probe pH monitoring is mandatory. At last, some aspects of reflux therapy are explained.

No Association between Gastroesophageal Reflux and Cancers of the Larynx and Pharynx

PURPOSE

To examine the proposed relation between gastroesophageal reflux disease and cancers of the larynx and pharynx.

EXPERIMENTAL DESIGN

A cohort of 66,965 patients with discharge diagnoses of heartburn, hiatal hernia, or esophagitis was identified in the Swedish Inpatient Register. We observed a total of 376,622 person-years in the cohort. Identification of laryngeal and pharyngeal cancers was achieved through the Swedish Cancer Register. Standardized incidence ratios, the ratio of the observed to the expected number of cancers, derived from the general Swedish population and adjusted for sex, age, and calendar year, was used to estimate the relative risk.

RESULTS

During follow-up, 30 cases of laryngeal and 31 cases of pharyngeal cancer were detected in the cohort. Slightly increased risks of laryngeal [relative risk, 1.6; 95% confidence interval (CI), 1.1-2.2] and pharyngeal carcinomas (relative risk, 1.9; 95% CI, 1.3-2.8) were observed in the total reflux cohort. After stratification to exclude cohort members with a diagnosis of alcoholism, no significant increase in the risk of laryngeal (relative risk, 1.3; 95% CI, 0.8-2.0) or pharyngeal carcinomas (relative risk, 1.0; 95% CI, 0.5-1.6) was found compared with the general population. Furthermore, there were no dose-response patterns of the risk for laryngeal and pharyngeal cancers with years of cohort follow-up, indicators of reflux severity, or specificity of reflux diagnosis.

CONCLUSION

This study provides no evidence in support of the proposed association between gastroesophageal reflux disease and cancers of the larynx or pharynx.

Effects of gastroesophageal reflux disease in laryngeal carcinoma

Gastroesophageal reflux disease is associated with various otolaryngological disorders. The aim of this retrospective study was to determine the role of gastroesophageal reflux disease in the development of laryngeal squamous cell carcinoma (SCC) in non-smoking and non-drinking patients. The study population consisted of 36 consecutive non-smoking and non-drinking patients with histologically confirmed SCC of the larynx. As a control, a group of 125 lifetime non-smoking and non-drinking cancer-free subjects were selected. Patients with laryngeal cancer had a higher prevalence of gastroesophageal reflux disease than the control subjects (P < 0.0001). Our results confirm the fact that gastroesophageal reflux disease in itself is associated with an increased risk of laryngeal cancer.

Fundoplication for laryngopharyngeal reflux disease

BACKGROUND

Laryngopharyngeal reflux (LPR) disease arises from the effects of refluxed gastric contents on the proximal aerodigestive tract. LPR patients are often lumped into the category of "atypical" reflux. LPR symptoms are hoarseness, globus, cough, and pharyngitis. Severe disease is associated with subglottic stenosis and laryngeal cancer. Treatment includes lifestyle modifications and medications. The role of fundoplication for LPR has yet to be defined.

STUDY DESIGN

Forty-one patients underwent fundoplication for LPR. They were prospectively followed with three outcomes measures: The Reflux Symptom Index, a laryngoscopic grading scale (Reflux Finding Score), and a reflux-based specific quality-of-life scale.

RESULTS

Average early followup was at 4 months and late followup was at 14 months. The Reflux Symptom Index improved by 5.4 early (p < 0.05) and 6.5 late (p < 0.05). Improvement between early and late periods approached significance (p < 0.09). Reflux Finding Score improved 3.8 (p < 0.05) early and 4.4 (p < 0.05) late. The Quality of Life Index improved 0.6 early and 2.3 (p < 0.05) late. By Reflux Symptom Index criteria, 26 patients were improved early versus 35 late (p < 0.05). Factors associated with poor outcomes were structural laryngeal changes in five patients (p < 0.05) and no response to proton pump inhibitors in six patients (p < 0.05).

CONCLUSIONS

Fundoplication augments treatment of LPR. Improvement of symptoms continues past the first 4 months. Laryngoscopy is critical in patient selection because selected findings are associated with outcomes, diagnosis, and management.

Risk of laryngeal cancer by occupational chemical exposure in Turkey

Laryngeal cancer is the second most common cancer among men in Turkey. In this hospital based case-control study, we evaluated laryngeal cancer risks from occupational chemical exposures. We analyzed 940 laryngeal cancer cases and 1519 controls. Occupational history, tobacco, and alcohol use and demographic information were obtained by a questionnaire. The job and industries were classified by special seven-digit codes. We calculated odds ratios (ORs) and 95% confidence intervals (CIs) based on a developed exposure matrix for chemicals, including diesel exhaust, gasoline exhaust, polycyclic aromatic hydrocarbons (PAHs), formaldehyde, and solvents. An excess of laryngeal cancer occurred with diesel exhaust (OR=1.5, 95% CI=1.3-1.9), gasoline exhaust (OR=1.6, 95% CI=1.3-2.0), and PAHs (OR=1.3, 95% CI=1.1-1.6). There was a dose-response relationship for these substances with supraglottic cancers (P<0.000). The PAH association only occurred among those who also had exposure to diesel exhaust.

Opium and risk of laryngeal cancer

OBJECTIVES/HYPOTHESIS

The study was performed to investigate the possible association between opium dependency and laryngeal cancer.

STUDY DESIGN

A hospital-based, group-matched, case-control study was presented.

METHODS

Ninety-eight patients with laryngeal cancer and 312 age- and gender-matched control subjects were selected at the otorhinolaryngology ward of a referral university-affiliated hospital. Data on cigarette smoking and alcohol and opium dependency were collected before surgery through semi-structured interview.

RESULTS

The crude odds ratios of laryngeal cancer were 15.07 (95% confidence interval [CI], 6.92-32.8 [P <.0001]) for cigarette smoking, 21.55 (95% CI, 10.54-44 [P <.0001]) for opium dependency, and 1.84 (95% CI, 1.008-3.38 [P <.048]) for male gender. Because of strong associations, a logistic regression model was prepared; the odds ratio for gender in the final model was 0.87 (95% CI, 0.39-1.92 [P =.11]). According to the results, it seemed that gender was not an independent risk factor for laryngeal cancer. Also, the adjusted odds ratios for smoking (5.21) (95% CI, 2.33-11.67 [P <.002]) and opium dependency (10.74) (95% CI, 5.76-20.02 [P <.002]) were lower than the crude odds ratios, but both ratios were significant. The mean patient ages were 55.1 years (SD = 12.05 y) in opium-dependent patients and 65.6 years (SD = 12.8 y) in opium-nondependent patients (P =.01).

CONCLUSION

The results of the study suggest that opium dependency is not only an independent possible risk factor for laryngeal cancer but also significantly increases the likelihood of developing of the disease at a younger age.

Cell biology of laryngeal epithelial defenses in health and disease: further studies

This is the second annual report of an international collaborative research group that is examining the cellular impact of laryngopharyngeal reflux (LPR) on laryngeal epithelium. The results of clinical and experimental studies are presented. Carbonic anhydrase (CA), E-cadherin, and MUC gene expression were analyzed in patients with LPR, in controls, and in an in vitro model. In patients with LPR, we found decreased levels of CAIII in vocal fold epithelium and increased levels in posterior commissure epithelium. The experimental studies confirm that laryngeal CAIII is depleted in response to reflux. Also, cell damage does occur well above pH 4.0. In addition, E-cadherin (transmembrane cell surface molecules, which have a key function in epithelial cell adhesion) was not present in 37% of the LPR laryngeal specimens. In conclusion, the laryngeal epithelium lacks defenses comparable to those in esophageal epithelium, and these differences may contribute to the increased susceptibility of laryngeal epithelium to reflux-related injury.

Intralesional Cidofovir for the Treatment of Severe Juvenile Recurrent Respiratory Papillomatosis: Long-Term Results in 4 Children

OBJECTIVE: We sought to determine the efficacy of intralesional injection of cidofovir in improving resolution of recurrent respiratory papillomatosis (RRP).

STUDY DESIGN AND SETTING: We conducted a prospective, observational trial at an academic tertiary children's hospital.

RESULTS: Four children with RRP requiring more than 6 surgical excisions per year were treated with intralesional cidofovir. Cidofovir (5 mg/mL) was injected into airway sites where papillomas had just been excised using sharp technique. Each patient had 6 treatments performed 6 to 8 weeks apart. Biopsies confirmed benign papilloma lesions in all cases. During treatment with intralesional cidofovir there was diminished growth of the papillomas in each patient. Once cidofovir treatment was stopped, the rate of regrowth and frequency of surgical excision returned to pretreatment levels in 3 of the 4 patients.

CONCLUSIONS: Intralesional cidofovir may provide benefit in reducing the rate of RRP growth while under treatment, but RRP severity returned to pretreatment levels once cidofovir treatment was stopped using this treatment program.

Second primary cancers in patients with laryngeal cancer: a population-based study

BACKGROUND

Literature regarding incidence of site-specific second cancers after laryngeal cancer is limited. Risk factors associated with second primaries are unknown.

METHODS

Second primaries after laryngeal cancer in the SEER database (1973-1996) were analyzed for incidence, relative risk compared with the general population, and potential risk factors, including radiotherapy. Information on chemotherapy and tobacco smoking was not available in the SEER database.

RESULTS

Of 20,074 laryngeal cancer patients surviving at least 3 months, 3533 (17.6%) developed second cancers. The cumulative risk of developing a second cancer was 26% at 10 years and 47% at 20 years. Compared with age-adjusted, gender, and tumor-specific rates in the general population, laryngeal cancer patients had higher risks of second cancers overall (observed-to-expected ratio [O/E] = 1.68, 95% confidence interval [CI] = 1.58-1.79), head-and-neck (4.81 [4.31-5.58]), esophageal (3.99 [3.29-4.83]), and lung (3.56 [3.34-3.79]) cancer. Advanced age at initial diagnosis was associated with increased risks of second cancers (p = 0.0001). Radiotherapy was associated with increased risk of second cancers overall (relative risk [RR] = 1.10 [1.02-1.18], p = 0.012), especially second cancers of the lung (RR = 1.18, [1.05-1.33], p = 0.006) and possibly second cancers of the head and neck (RR = 1.26, [0.99-1.60], p = 0.061). Radiotherapy was associated with a 68% excess risk (RR = 1.68, [1.16-2.43], p = 0.007) of developing a second head-and-neck cancer in patients who survived more than 5 years. Second primary was associated with a poor survival (p = 0.0001).

CONCLUSIONS

Second cancers after laryngeal cancer are common, especially for long-term survivors. Radiotherapy was associated with a small increased risk of developing second cancers overall and long-term risk of head-and-neck cancers. This data should be interpreted with caution in light of the lack of information on chemotherapy and tobacco smoking in the SEER database. Prevention and early detection are indicated.

Risk factors and prognosis of anterior commissure versus posterior commissure T1-T2 glottic cancer

For better understanding of the causation and behavior of T1-T2 commissural glottic laryngeal tumors, we retrospectively analyzed risk factors and outcome related to T class and type of therapy for tumors involving the anterior (184 cases) or the posterior (60 cases) commissure. The patients' smoking habits and alcohol consumption were similar, regardless of involved subsite. The disease-free interval was longer after surgery than after radiotherapy. The survival rates after recovery upon relapse were similar among subsites, T classes, and types of therapy. In anterior commissure tumors, the larynx remained preserved more frequently after partial laryngeal resection than after radiotherapy, and was more frequently preserved the lower the T class. In posterior commissure tumors, larynx preservation was less frequent and apparently independent of type of therapy or T class. In conclusion, smoking and alcohol consumption play similar pathogenetic roles in either subsite; partial laryngeal resection gave a higher rate of laryngeal preservation than did radiotherapy; and anatomic peculiarities of the subsites influence tumor behavior.

The role of gastroesophageal reflux in the pathogenesis of laryngeal carcinoma

Gastroesophageal reflux (GER) has been strongly associated with carcinogenesis of the lower esophagus and development of several otolaryngologic disorders. Epidemiologic studies support concept that the malignant transformation of laryngeal mucosal surfaces is due to GER-initiated chronic laryngeal inflammation. However, large clinical studies with matched control groups and further experimental investigations are necessary to ascertain the relationship between reflux and laryngeal carcinoma. This review stresses that early diagnosis of GER disease, based on clinical suspicion, ambulatory 24-hour double-probe pH monitoring, and endoscopic examination, as well as effective treatment of reflux, are considered the keys for relief of symptomatology and preventing the chronic irritation of the laryngeal mucosa that may contribute to the development of laryngeal carcinoma.

Management of common voice problems: Committee report

OBJECTIVE

This report provides the reader with a state-of-the-art update on a number of common voice problems that require phonosurgical intervention.

STUDY DESIGN AND SETTING

This multiauthor review is not a position statement of the American Academy of Otolaryngology-Head and Neck Surgery (AAOHNS) and may reflect institutional preference and/or bias. It arose from a panel discussion at the AAOHNS meeting in 2000.

RESULTS

We provide a review of the genesis and management of papillomatosis, dysplastic glottal epithelium, arytenoid granulomas, Reinke's edema, and vocal-fold paralysis.

CONCLUSIONS AND SIGNIFICANCE

In the past decade, there has been a dramatic expansion of knowledge regarding a variety of voice disorders and associated treatment. There has been a convergence of basic science investigations in anatomy, physiology, and pathology with clinical trials of treatment, both surgical and nonsurgical. This information should provide the reader with current insight into critical management issues of the aforementioned disorders.

Prognostic significance of p53, bax and bcl-2 gene expression in patients with laryngeal carcinoma

AIM

This study was designed to examine the prognostic significance of the coexpression of three genes (bax, bcl-2 and p53) which play a critical role in the apoptotic mechanisms in patients with squamous cell laryngeal carcinoma.

MATERIALS AND METHODS

The immunohistochemical expression of bcl-2, bax and p53 genes was retrospectively examined in 38 patients with squamous cell laryngeal carcinoma and in five controls (necrotomic tissue). Tissue specimens were obtained both during the diagnostic biopsy and at the time of surgery. Clinicopathological and survival data were correlated with the staining results.

RESULTS

Bcl-2 protein expression (P=0.0472), stage (P=0.0087) and lymph-node involvement (P=0.0488) were found to be independent prognostic factors. Increased bcl-2 protein expression correlated with a better 5-year survival (P=0.0472). Patients who were bcl-2(-)/p53(-) (n=25) or bax(+)/bcl-2(-) (n=13) had a significantly worse overall survival (P=0.0305 and P=0.0482, respectively). Similarly, patients who were bax(+)/bcl-2(-)/p53(-) (n=11) also had a worse 5-year survival compared with the rest of the group (P=0.0088). Changes that were noticed in bax and p53 protein expression from the time of biopsy until the time of surgery did not correlate with a significant increase in the overall survival.

CONCLUSIONS

The expression of bcl-2 gene appears to be an independent prognostic factor for patients with laryngeal carcinoma. The coexpression of the genes studied can be used to determine aggressive clinical phenotypes.

Gastroesophageal reflux disease is a risk factor for laryngeal and pharyngeal cancer

OBJECTIVE

Gastroesophageal reflux disease (GERD) is a proposed risk factor for developing laryngeal and pharyngeal cancers. No controlled study has examined this association.

METHODS

A case-control-study was performed using the computerized hospitalization and outpatient databases of the US Department of Veterans Affairs. All patients, who were veterans, had been identified as being hospitalized with laryngeal or pharyngeal during 1991 to 1997. In addition, all persons diagnosed with laryngeal or pharyngeal cancer in 1999 in the outpatient files were identified. From the same patient populations, four nonmatched control subjects were randomly assigned for each case. The medical history for cases and controls was retrospectively searched for GERD diagnoses, tobacco use, and alcohol dependence. Multivariable logistic regression analyses were performed to assess the risk factors for laryngeal and pharyngeal cancers.

RESULTS

A total of 8,228 hospitalized patients with laryngeal cancers and 1,912 with pharyngeal cancers were compared to 32,912 and 7,648 hospitalized controls, while 9,292 outpatients with laryngeal cancer and 2,769 outpatients with pharyngeal cancer were compared with 37,168 and 11,076 outpatient controls without cancer. Among hospitalized persons, the prevalence of GERD was higher among patients with laryngeal cancer (8.9 vs 4.0%, p < 0.0001) and pharyngeal cancer (6.2 vs 3.8%, p < 0.0001). In a multivariable logistic regression analysis that was controlled for age, gender, ethnicity, smoking, and alcohol, GERD was associated with an adjusted odds ratio (OR) of 2.40 for laryngeal cancer among hospitalized patients (95% CI 2.15-2.69, p < 0.0001) and an adjusted OR of 2.38 (95% CI 1.87-3.02, p < 0.0001) for pharyngeal cancer. For outpatients, GERD was associated with an adjusted OR = 2.31 (95% CI 2.10-2.53) for laryngeal cancer and adjusted OR = 1.92 (95% CI 1.72-2.15).

CONCLUSIONS

Among US veterans, the risk for laryngeal or pharyngeal cancers is modestly increased in the presence of GERD. This effect seems to be independent of age, gender, smoking, and alcohol intake.

Glutathione S-transferase pi in squamous cell carcinoma of the head and neck

OBJECTIVES/HYPOTHESIS

Oxidative/reductive (redox) DNA damage from radical species such as nitric oxide (NO*) are increasingly being implicated in the development of cancer. Moreover, redox-protective cellular mechanisms, such as glutathione S-transferase, may determine cellular susceptibility to this redox-mediated damage.

METHODS

Formalin-fixed, paraffin-embedded tissue samples of 11 normal oral mucosa, 15 reactive/dysplastic lesions, and 131 head and neck squamous cell carcinomas (HNSCCs) were immunohistochemically stained using a polyclonal antibody against glutathione S-transferase pi (GST-pi). Slides were reviewed in a blinded fashion by the study pathologist (G.K.H.) and intensity was graded, noting the pattern of immunostaining. These staining characteristics were compared with those obtained using monoclonal antibodies against endothelial constitutive nitric oxide synthase (ecNOS) and nitrotyrosine, a marker of NO*'s pathological nitrosylation of proteins on serial sections of the same tissue. Patient charts were reviewed and clinical data collected.

RESULTS

The expression of GST-pi was significantly increased in reactive/dysplastic and HNSCC samples compared with normal squamous mucosa (P < .001 for both). Furthermore, among the carcinomas the expression of GST-pi was significantly increased in higher-grade lesions (P < .02). The expression of GST-pi correlated highly with the expression of ecNOS and nitrotyrosine (P < .0001 for both).

CONCLUSIONS

These findings demonstrate that GST-pi is upregulated in conjunction with the NO*-generating ecNOS isoform and implicate GST-pi in protecting HNSCC from the cytotoxic effects of high concentrations of NO* found in the tumor bed.

Does waiting time for radiotherapy affect local control of T1N0M0 glottic laryngeal carcinoma?

This is a retrospective study of 362 patients with a T1N0M0 glottic laryngeal carcinoma treated by radiotherapy. Waiting time was defined as time from the day of histopathological diagnosis to the first day of radiotherapy. The Cox regression model was used to analyse the influence of waiting time for radiotherapy on the incidence of recurrence. The median follow-up time was 4.4 years. The median waiting time for radiotherapy was 43 days. Local recurrences were found in 58 patients. There was no significant correlation (P= 0.88) between waiting time and the outcome of early glottic cancer as analysed by Cox regression. This retrospective study did not demonstrate an effect of waiting time for radiotherapy on the outcome of early glottic laryngeal cancer.

Influence of tobacco and alcohol on the stage of laryngeal cancer at diagnosis

OBJECTIVE

This study sought to examine the influence of cigarette smoking and alcohol consumption on the stage of laryngeal cancer at diagnosis.

STUDY DESIGN

A retrospective review of 499 laryngeal cancer patients diagnosed between 1978 and 1997 was conducted.

METHODS

Parameters that included smoking history, history of alcohol consumption, and the tumor stage and location at diagnosis were analyzed using the proportional odds model, correlation coefficient, and Student t test.

RESULTS

Three hundred sixteen patients met the inclusion criteria, and 180 (56%) had advanced-stage disease at the time of presentation. The statistical model demonstrated a small but significant relationship between tobacco and alcohol on the stage of laryngeal cancer at diagnosis. Patients diagnosed with an advanced-stage tumor (stage III or IV) smoked a significantly greater amount and were more likely to be heavy drinkers than those diagnosed with a localized laryngeal cancer.

CONCLUSIONS

Our results demonstrate that for every incremental increase in pack years of smoking, there is a small but measurable increase in the odds that a patient's laryngeal cancer will be stage III or IV at diagnosis. Likewise, being a "heavy" drinker as opposed to a "social" drinker raises the likelihood of an advanced tumor. Given the preventable nature of these risk factors, the moderation of alcohol consumption and cessation of smoking is prudent advice that should be conveyed to all patients.

Increased protein nitrosylation in head and neck squamous cell carcinogenesis

BACKGROUND

Nitric oxide (NO.) and its metabolic byproducts are implicated in carcinogenesis. We examined a marker of NO.-species' pathologic protein nitrosylation, nitrotyrosine, during head and neck squamous cell carcinoma (HNSCCa) development. Materials and Methods Paraffin-embedded tissue samples of normal oral mucosa, squamous hyperplasia/dysplasia, and HNSCCa were immunohistochemically analyzed for staining intensity using an antinitrotyrosine monoclonal antibody, and correlated with retrospective clinical data.

RESULTS

Significantly higher staining was noted in reactive, dysplastic and HNSCCa samples compared with samples of normal mucosa. Additionally, significant differences in staining were found between various primary sites of the upper aerodigestive tract. Lastly, individual inflammatory cells also stained intensely.

CONCLUSIONS

Increasing amounts of nitrotyrosine staining were found in reactive/dysplastic and HNSCCa lesions compared to normal squamous mucosa. Inflammatory cell staining implicates NO. as a possible mediator of immunosuppression. Given these findings, the role of NO. in mutations leading to and the immunosuppression found in HNSCCa warrants further investigation.