The role of acid and alkaline reflux in laryngeal squamous cell carcinoma

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.

Impact of bile acids on the severity of laryngo-pharyngeal reflux

OBJECTIVES

The primary end point of this study was to evaluate the impact of bile acids on severity of laryngo-pharyngeal reflux (LPR) and the possible correlation with esophagitis and upper airway malignancies. The second end point was to evaluate if salivary bile acids and molecules other than pepsin might serve as diagnostic biomarkers of LPR.

DESIGN

Observational prospective comparative study.

SETTING

Otorhinolaryngology unit of a tertiary hospital.

PARTICIPANTS

Sixty-two consecutive adult outpatients suspected of LPR.

MAIN OUTCOME MEASURES

Bile acids, bilirubin and pepsinogen I-II were measured in saliva. Patients underwent pH metry and based on the results of bile acids were subdivided as acid, mixed and alkaline LPR.

RESULTS

Significantly higher Reflux Findings Score (RFS) and Reflux Symptoms Index (RSI) were seen in patients with alkaline and mixed LPR compared to acid LPR. Salivary bile acids >1 µmol/L seem to be a reliable indicator of the severity of LPR. Compared to those without, patients with esophagitis or a history of upper airway malignancy have high concentrations of bile acids in saliva. Among the molecules studied, bile acids were the most suitable for diagnosis of LPR, with a sensitivity of 86% and a positive predictive value of 80.7%.

CONCLUSIONS

Our data suggest that high concentrations of bile acids are associated with higher values of RSI and RFS in LPR as well as a higher risk of esophagitis and history of upper airway malignancies. We finally observed that bile acids provided the best biometric parameters for diagnosis of LPR among the molecules tested.

Laryngopharyngeal Reflux in Hypertrophic Laryngeal Diseases

OBJECTIVES

To evaluate the characteristics of laryngopharyngeal reflux (LPR) in patients with different hypertrophic laryngeal diseases and to explore the relationship between LPR and these diseases.

METHODS

A retrospective analysis was performed. The clinical data of 154 patients were collected. According to their diagnoses, patients were divided into 3 groups. Group 1 included 49 patients with vocal cord polyps. Group 2 contained 52 patients with vocal cord leukoplakia. Group 3 included 53 patients with laryngeal carcinoma. The reflux symptom indexes (RSIs), reflux finding scores (RFSs), and Ryan scores of all patients were evaluated and compared.

RESULTS

Patients with vocal cord polyps were the youngest of the 3 groups, and those with laryngeal carcinoma were the oldest. A male preponderance emerged in each group. In total, 128 patients (83.12%) had positive RSI/RFS values and 60 (60/146, 41.1%) patients had positive Ryan scores. The positive RSI/RFS rates of both groups 1 and 2 (89.80% and 92.16%, respectively) were significantly higher than that of group 3 (69.81%). Moreover, the positive Ryan score rates in both groups 1 and 2 (39.58% and 53.85%, respectively) were significantly higher than that of group 3 (28.26%).

CONCLUSIONS

Laryngopharyngeal reflux occurs in many patients with vocal cord polyps, vocal cord leukoplakia, and vocal cord carcinoma, indicating that LPR may be important in the pathogenesis of these diseases. Laryngopharyngeal reflux occurs more common in patients with vocal cord polyps and leukoplakia and less common in those with laryngeal carcinoma, suggesting the role of LPR on these diseases may be different.

Laryngopharyngeal reflux disease, prevalence and clinical characteristics in ENT department of a tertiary hospital Tanzania

Background

Laryngopharyngeal reflux disease (LPRD) is a condition with nonspecific symptoms and most of times patients present late with advanced disease which may predispose to malignancy. The magnitude and clinical characteristics of this condition are not well known among patients attending Otorhinolaryngology services in Tanzania.

Materials and methods

This was a hospital based descriptive cross sectional study, conducted in the wards and clinics of Otorhinolaryngology department of Muhimbili National Hospital. Patients with symptoms of Laryngopharyngeal reflux disease were included in the study. Data was collected using questionnaires and clinical examination forms, were processed and analysed by using SPSS. Results presented in frequency tables, cross tabulations and figures.

Results

This study recruited 256 participants among them males were 131(51.2%).The mean age was (41.38 ± 13.94) years. Prevalence of Laryngopharyngeal reflux disease was 18.4% without gender predilection. The commonest symptoms were globus sensation, hoarseness of voice and excessive urge to clear the throat with 95.7%, 88.1% and 83.0% respectively while the most observed signs were thick endolaryngeal mucus, Vocal cord oedema and partial ventricular obliteration with 90.9%, 88.6% and 72.7% respectively. Lying down less than two hours after meal and spices foods consumption were the leading risk factors. Hypertension and Diabetes Mellitus type 2 were the most prevalent co morbid conditions associated with Laryngopharyngeal reflux disease.

Conclusion

The prevalence of Laryngopharyngeal reflux disease is high among patients attending Otorhinolaryngology services at Muhimbili national hospital. All patients with Laryngopharyngeal reflux disease related symptoms should get thorough evaluation for early diagnosis and treatment.

Pepsin and Laryngeal and Hypopharyngeal Carcinomas

Laryngeal and hypopharyngeal carcinomas are common malignant tumors of the head and neck, and the incidence of both is increasing. Laryngopharyngeal reflux refers to the retrograde flow of gastric contents into the larynx, oropharynx, and/or nasopharynx. It remains controversial whether laryngopharyngeal reflux is a risk factor for laryngeal and hypopharyngeal cancers. The refluxing substances mainly include hydrochloric acid, pepsin, and occasionally bile acids and bile salts, as well as bacteria that colonize the gastrointestinal tract. Loss of epithelium in the mucous membrane of the larynx and hypopharynx is thought to be caused by pepsin. Here, we review the relationships between laryngopharyngeal reflux and both laryngeal and hypopharyngeal carcinomas, as well as the significance of pepsin, methods of clinical detection, and the mechanism of carcinogenesis.

Cell proliferation and invasion is promoted by circSERPINA3 in nasopharyngeal carcinoma by regulating miR-944/MDM2 axis

Growing evidence has demonstrated that in tumor progression, circular RNAs (circRNAs) play important roles. However, the roles of circRNAs in nasopharyngeal carcinoma (NPC) have not been fully elucidated. In this study, it was demonstrated that that hsa_circ_0033074 (circSERPINA3) expression was found to be significantly upregulated in NPC tissues and cell lines. CircSERPINA3 inhibition significantly attenuated the invasion and proliferation abilities of NPC cells. The mechanism by which circSERPINA3 interacted with miR-944 was identified and MDM2 was demonstrated to function as a target gene of miR-944. Rescue experiments showed that miR-944 inhibitors or MDM2 overexpression reserved the effects of circSERPINA3 knockdown on NPC progression. Therefore, our study uncovered the circSERPINA3/miR-944/MDM2 axis in NPC, which may be a potential NPC therapeutic target.

The role of bile reflux and its related NF-κB activated pathway in progression of hypopharyngeal squamous cell cancer

BACKGROUND

Prognosis for hypopharyngeal cancer is usually poor, and recurrence is common. Identifying new factors or related mechanisms that promote its progression may have clinical implications. Although, recent studies support bile reflux in hypopharyngeal carcinogenesis, it remains to be explored how bile and its related NF-κB activated pathway may further affects its progression in already established hypopharyngeal cancer.

METHODS

Hypopharyngeal squamous cell carcinoma (HSCC) cell lines, FaDu and UMSCC11A, both negative for HPV, were repetitively exposed to bile acids (400 μM) at variable pH points (4.0, 5.5 and 7.0). Immunofluorescence, western blotting, luciferase assay, and qPCR were used to detect NF-κB activation, bcl-2 overexpression and gene expression.

RESULTS

Bile at strongly acidic pH (4.0) potentiated the activation of NF-κB and its related mRNA phenotype in HSCC cells. IL-6, TNF-α, and BCL2 were found among the highest overexpressed genes as was previously found in HSCCs excised from patients with documented biliary reflux. An enhanced transcriptional activity of EGFR, RELA, STAT3, and WNT5Α and higher survival rates were observed in HSCC cells exposed to acidic bile compared to those exposed to bile at weakly acidic or neutral pH.

CONCLUSION

Our novel findings support the observation that bile reflux has the potential for actively influencing the progression of hypopharyngeal cancer, mediated by NF-κB. In patients with hypopharyngeal cancer and known gastroesophageal reflux disease, antacid therapy may exert a role in furthering control of disease recurrence and progression.

Association of Gastroesophageal Reflux With Malignancy of the Upper Aerodigestive Tract in Elderly Patients

Importance

Chronic inflammatory states have been linked to the development of malignancy. Gastroesophageal reflux disease (GERD) is a known risk factor for esophageal adenocarcinoma as the end result of chronic inflammatory changes.

Objective

To investigate the association of GERD with the risk of malignancy in the upper aerodigestive tract (UADT).

Design, Setting, and Participants

We used the Surveillance, Epidemiology, and End Results (SEER)-Medicare database to conduct a case-control study of individuals in the United States who had been added from January 2003 through December 2011 and were 66 years or older. The study included patients diagnosed with malignancy of the larynx, hypopharynx, oropharynx, tonsil, nasopharynx, and paranasal sinuses. GERD was examined as an exposure. Controls were matched from a 5% random sample of Medicare beneficiaries without cancer. Multivariable unconditional logistic regression was performed.

Main Outcomes and Measures

Incidence of invasive malignancies of the UADT.

Results

A total of 13 805 patients (median [range] age, 74 [66-99] years; 3418 women [24.76%] and 10 387 men [75.24%]) with malignancy of the UADT were compared with 13 805 patients without disease and were matched for sex, age group, and year of diagnosis. GERD was associated with a greater odds of developing malignancy of the larynx (adjusted odds ratio [aOR], 2.86; 95% CI, 2.65-3.09), hypopharynx (aOR, 2.54; 95% CI 1.97-3.29), oropharynx (aOR, 2.47; 95% CI, 1.90-3.23), tonsil (aOR, 2.14; 95% CI, 1.82-2.53), nasopharynx (aOR, 2.04; 95% CI, 1.56-2.66), and paranasal sinuses (aOR, 1.40; 95% CI, 1.15-1.70).

Conclusions and Relevance

GERD is associated with the presence of malignancy of the UADT in the US elderly population. This epidemiological association requires further examination to determine causality and diagnostic utility.

Biliary tumorigenic effect on hypopharyngeal cells is significantly enhanced by pH reduction

Biliary reflux has been considered a potential risk factor in upper aerodigestive tract malignancies. It is not yet clearly known how pH affects the bile-induced activation of NF-κB and its related oncogenic pathway previously linked to hypopharyngeal carcinogenesis. In this study, repetitive applications of conjugated primary bile acids with unconjugated secondary bile acid, deoxycholic acid (DCA), on human hypopharyngeal primary cells reveal that strongly acidic pH (4.0) optimally enhances the tumorigenic effect of bile, by inducing activation of NF-κB, STAT3 nuclear translocation, bcl-2 overexpression and significant overexpression of the oncogenic mRNA phenotype, compared to weakly acidic pH (5.5) or neutral pH (7.0). As the pH becomes less acidic the partially activated primary bile acids and activated DCA begin to exert their influence; however, with significantly less intensity compared to bile acids at strongly acidic pH. Our findings suggest that biliary tumorigenic effect is strongly pH dependent. Controlling pH during reflux events may be therapeutically effective in reducing the potential risk of bile-induced hypopharyngeal cancer.

Gastroesophageal and Laryngopharyngeal Reflux Associated With Laryngeal Malignancy: A Systematic Review and Meta-analysis

BACKGROUND & AIMS

Gastric reflux may lead to chronic mucosal inflammation and contribute to development of laryngeal malignancies, although there is controversy over this association. We performed a systematic review and meta-analysis to assess this relationship and determine the risk of laryngeal malignancy in patients with reflux disease.

METHODS

We performed a systematic review and meta-analysis, searching MEDLINE, EMBASE, and Web of Science databases from 1900 through April 9, 2018, for observational studies of adults reporting associations between gastroesophageal reflux disease (GERD) and/or laryngopharyngeal reflux and the risk of having or developing laryngeal malignancies. An itemized assessment of the risk of bias was conducted for each study that met inclusion criteria. The meta-analysis was performed using the Mantel-Haenszel method with random effects to account for heterogeneity. We performed subgroup analyses to determine the effect of reflux type, study design, diagnostic method, and confounding variables on the overall risk.

RESULTS

Of the 957 studies that were identified during systematic review, 18 case-control studies met the criteria for analysis. Our meta-analysis showed that reflux disease significantly increased the risk of laryngeal malignancy (odds ratio, 2.47; 95% CI, 1.90-3.21; P < .00001; I² = 94%). This association remained when controlling for patient smoking and drinking (odds ratio, 2.07; 95% CI, 1.26-3.41). There was no statistically significant difference in risk of laryngeal malignancies between patients with GERD vs laryngopharyngeal reflux (P = .44).

CONCLUSIONS

In a systematic review and meta-analysis, we found a significant association between reflux disease and the presence of laryngeal malignancy. Prospective studies should be performed to examine this relationship.

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.

ATF3-Dependent Regulation of EGR1 in vitro and in vivo

BACKGROUND/AIMS

Activating transcription factor 3 (ATF3) and early growth response protein 1 (EGR1) are reported to interact, but their use as prognostic factors in cancer is discussed controversially.

METHODS

We measured ATF3 and EGR1 gene expression changes in human mini-organ cultures (MOCs) of healthy nasal epithelia, UM-SCC-22B, and FADUDD cells after acid reflux exposure. Next, ATF3 and EGR1 gene expression was analysed in tumour tissues and related to the median expression of autologous reference tissue samples.

RESULTS

ATF3 and EGR1 mRNA expression was significantly reduced after consecutive exposure of MOCs at pH <7.0 to artificial gastric juice (refluxate). In contrast, ATF3 mRNA was upregulated significantly within the first hour of incubation. EGR1 mRNA exhibited no significant changes. The analysed cell lines exhibited a cell line-specific alteration. In FADUDD cells, the upregulation of EGR1 was significant after refluxate exposure, but in HN-SCC 22B, no significant changes were detected. The analysis of the HNSCC samples confirmed the heterogeneous data of the literature.

CONCLUSION

The data maintain the hypothesis that ATF3 and EGR1 are involved in the beginning of inflammatory processes. Whether these two transcription factors act as tumour suppressors or promoters is context dependent and warrants analysis in further studies.

Condroradionecrose de laringe após radioterapia

RESUMO Objetivo: estudar a condroradionecrose de laringe por complicação de radio-quimioterapia para tratamento do câncer de laringe e propor um fluxograma de tratamento com a utilização de câmara hiperbárica. Métodos: estudo retrospectivo de pacientes portadores de carcinoma de laringe admitidos em dois hospitais terciários num período de cinco anos. Resultados: de 131 pacientes portadores de câncer de laringe, 28 foram submetidos à radio e quimioterapia exclusiva e destes, três evoluíram com condroradionecrose. O tratamento destes pacientes foi realizado com câmara hiperbárica e com desbridamento cirúrgico, conforme proposição do fluxograma. Todos os pacientes tiveram a laringe preservada. Conclusão: a incidência de condroradionecrose de laringe por complicação de radioterapia e quimioterapia em nossa casuística foi de 10,7% e o tratamento com oxigenoterapia hiperbárica, com base no nosso fluxograma, foi efetivo no controle desta complicação.

Duodenal Contents Reflux-Induced Laryngitis in Rats: Possible Mechanism of Enhancement of the Causative Factors in Laryngeal Carcinogenesis

Objectives:

The main factors considered responsible for the onset of laryngeal cancer are tobacco smoking and alcohol abuse. Recently, gastroesophageal reflux has also been implicated as a causative factor in several laryngeal disorders, including laryngeal cancer. However, the significance of gastroesophageal reflux in laryngeal cancer is controversial.

Methods:

We investigated the histologic features of the esophagus and larynx in a rat model of reflux of the duodenal contents. Cell proliferation was also evaluated in laryngeal samples by detection of Ki67 antigen.

Results:

In this reflux model, laryngitis with infiltration of inflammatory cells and proliferation of small mucous glands was evident from 10 weeks after operation, and basal cell hyperplasia around the epiglottis and hyperplastic changes in the larynx were detected at 30 weeks. No dysplastic or malignant lesions were detected in the laryngeal samples within the duration of the experiment, in spite of detection of malignancy in 31.3% of lesions in esophageal samples at 30 weeks. The Ki67 index at each week was significantly higher than that of the control animals.

Conclusions:

Previous studies have shown smoking and alcohol abuse to have refluxogenic effects. Reflux of duodenal contents causes laryngitis. Reflux does not appear to be an independent risk factor for laryngeal carcinogenesis, but it may enhance the acknowledged etiologic risk factors, namely, smoking and alcohol abuse, by promoting cell proliferation.

Human Lung Mucous Glands Manifest Evidence of the H+/K+-ATPase Proton Pump

Objectives:

The H+/K+-ATPase proton pump has been demonstrated in human laryngeal submucosal glands, and is not solely present in the parietal cells of the stomach. Although proton secretion is present in the lung, a variety of mechanisms have been elucidated. The hypothesis of this study is that the H+/K+-ATPase proton pump is one additional pathway of proton secretion in the human lung.

Methods:

Fourteen surgical lung specimens from 10 subjects were retrospectively obtained after approval from our Human Subjects Committee. Banked human stomach tissue was used for comparative positive and negative controls. Sections were immunostained with 2 monoclonal antibodies selectively reactive with alpha or beta subunits of the H+/K+-ATPase proton pump.

Results:

In the human lung, consistent staining for both subunits was present in the mucous gland cells and ducts in all specimens in which mucous glands were present (6 specimens from 5 subjects). Overall, weak to strong staining was present in focal areas within the multicellular mucous glands. There was only scant focal staining in the respiratory epithelium in 4 specimens. Stomach parietal cells exhibited strongly positive staining for both subunits of the proton pump. There was no staining in stomach cells that were not morphologically consistent with parietal cells.

Conclusions:

The H+/K+-ATPase proton pump is present in mucous cells and ducts in the human lung, with some variable expression noted. Proton pump inhibitor pharmacotherapy may have a site of action in the human lung, explaining some of the controversies otherwise attributable to interrelatedness of aerodigestive tract disease.

miR-21, miR-155, miR-192, and miR-375 Deregulations Related to NF-kappaB Activation in Gastroduodenal Fluid-Induced Early Preneoplastic Lesions of Laryngeal Mucosa In Vivo

Gastroduodenal refluxate found in the upper aerodigestive tract is not clinically uncommon. We recently demonstrated the neoplastic potential of gastroduodenal fluids (GDF) on hypopharyngeal mucosa, via NF-κB, using in vitro and in vivo models. Here we will explore the in vivo effect of GDF on laryngeal mucosa (LM) to induce early preneoplastic lesions related to NF-κB activation, along with deregulation of specific microRNA (miRNA) markers previously linked to laryngeal cancer. We used histological, immunohistochemical, automated quantitative analysis and quantitative polymerase chain reaction to examine LM from 35 C57Bl/6J mice previously treated with topical GDF against corresponding controls (4 experimental and 3 control groups; 5 mice/group). Our analysis showed that GDF produced early preneoplastic lesions in treated LM related to NF-κB activation. LM treated by acid and bile combination demonstrated significantly higher expression of the analyzed cell proliferation markers (Ki67, CK14, ∆Np63), oncogenic p-STAT3, and changes of cell adhesion molecules (E-cadherin, ϐ-catenin) versus untreated LM or LM exposed to acid alone (P < .0005). Furthermore, acidic bile but not neutral bile appeared to accelerate the expression of “oncomirs” miR-21, miR-155, and miR-192 (acidic bile versus neutral bile, P < .0001), while reducing tumor suppressor miR-375 (acidic bile versus neutral bile, P = .0137), previously linked to NF-κB and laryngeal cancer. Finally, acidic bile induced reduction of miR-34a, miR-375, and miR-451a, exhibiting an inverse correlation with NF-κB activation. SIGNIFICANCE: Bile in combination with acid has a selective tumorigenic effect on LM, inducing deregulation of “oncomirs” and tumor suppressor miRNAs, produced by NF-κB activation with molecular and early histopathological alterations linked to neoplastic transformation. Systematic acid suppression may in part convey a protective role.

Correlation between levels of expression of minichromosome maintenance proteins, Ki-67 proliferation antigen and metallothionein I/II in laryngeal squamous cell cancer

MCM2, MCM3 and MCM7 are minichromosome maintenance proteins found in dividing cells and they play a role in DNA synthesis. Increased MCM expression level is observed in cells of different cancer types. Additionally, metallothioneins (MT-I/II) are involved in control of cell proliferation and differentiation and changes of their expression are observed in many types of cancer. Ki-67 is known cancer cell proliferation antigen currently used in prognostic evaluation. The study material consisted of 83 laryngeal squamous cell cancer (LSCC) cases and 10 benign hypertrophic lesions of larynx epithelium as a control group. For the present study, laryngeal cancer cell line HEp-2 and human keratinocytes were employed, and to evaluate expression of all the markers, immunohistochemical method (IHC), immunofluorescence (IF) and western blot analysis were used. Statistical analysis showed strong positive correlation between expression of MCM2, MCM3, MCM7 and Ki-67 antigen in LSCC. Additionally, moderate positive correlation was observed between MCM3 and MT-I/II expression. In cancer cells, the level of expression of MCM3, MCM2, MCM7 and Ki-67 markers was increasing with the grade of LSCC malignancy. IF and western blot analysis showed higher MCM2, MCM3, MCM7 expression in HEp-2 cells in comparison to their expression in keratinocytes. MCM proteins might be useful markers of cell proliferation in LSCC.

Rabeprazole is effective for bile reflux oesophagitis after total gastrectomy in a rat model

AIM: To elucidate the effect of a proton pump inhibitor (PPI, rabeparazole) on oesophageal bile reflux in oesophagitis after total gastrectomy.

METHODS: Twenty-one 8-week-old male Wistar rats were studied. They were performed oesophagoduodenostomy of total gastrectomy to induce oesophageal reflux of biliary and pancreatic juice. Five rats were performed the sham operation (Sham). On post-operative day 7, they were treated with saline (Control) (n = 8) or PPI (rabeprazole, 30 mg/kg per day, ip ) (n = 8) for 2 wk. On post-operative 21, all rats were sacrificed and each oesophagus was evaluated histologically. Oesophageal injury was evaluated by macroscopic and microscopic findings as well as the expression of cyclooxygenase-2 (COX2). We measured bile acid in the oesophageal lumen and the common bile duct.

RESULTS: At 3 wk after surgery, a histological study analysis revealed an increase in the thickness of the epithelium, elongation of the lamina propria and basal cell hyperplasia in the oesophageal mucosa. The macroscopic ulcer score and microscopic ulcer length of the control group were significantly higher compared to those of the rabeprazole- treated group. The expression of COX2 was significantly increased according to the immunostaining in the control group compared to rabeprazole- treated group. Although there was no difference between the control and PPI groups in the total bile acid in the common bile duct, the bile acid activity in the oesophageal lumen was significantly decreased in the rabeprazole- treated group due to augmentation of the duodenal motor complex.

CONCLUSION: With this model, rabeprazole is good effect for reflux esophagitis after total gastrectomy from bile reflux. Bile acid is an important factor in the mucosal lesion induced by duodenal reflux.

Gastroesophageal reflux and carcinoma of larynx or pharynx: a meta-analysis

CONCLUSION

The meta-analysis supported the proposition that the prevalence of gastroesophageal reflux disease (GERD) was associated with laryngeal cancer, particularly in the hospital-based control group and diagnosed by esophagogastroduodenoscopy (EGD) or esophageal pH monitoring. However, no significant association was found between GERD and pharyngeal carcinoma.

OBJECTIVES

A number of studies have been conducted to investigate the relationship between gastroesophageal reflux and laryngeal or pharyngeal carcinoma. The conclusions are still debated.

METHODS

We conducted a systematic review of studies associated with the prevalence of GERD in laryngeal or pharyngeal cancer, published up to November 2013.Odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were estimated using random effects models or fixed effects models, according to heterogeneity I(2).

RESULTS

Ten studies were included in this meta-analysis. On average, GERD was significantly higher in the tumor tissue of the study group compared with normal tissue of the control group (OR = 2.17, 95% CI = 1.50, 3.14; random effects analysis). The pooled ORs for laryngeal carcinoma were 2.21 (95% CI = 1.53-3.19; I(2) = 97, random effects model) and 3.76 (95% CI = 0.21-67.48; I(2) = 94, random effects model) for pharyngeal carcinoma.

Reflux induces DNA strand breaks and expression changes of MMP1+9+14 in a human miniorgan culture model

Gastroesophageal reflux disease has been implicated in the pathogenesis of adenocarcinoma of the oesophagus. The same applies to laryngopharyngeal reflux (LPR) and squamous cell cancer of the head and neck, but so far, this link has not been proven. The impact of low pH and bile acids has not been studied extensively in cells other than oesophageal cancer cell lines and tissue. The aims of this study were to investigate the pathogenic potential of reflux and its single components on the mucosa of the upper respiratory tract. We measured DNA stability in human miniorgan cultures (MOCs) and primary epithelial cell cultures (EpCs) in response to reflux by the alkaline comet assay. As matrix metalloproteinases (MMPs) are involved in extracellular matrix remodelling processes and may contribute to cancer progression, we studied the expression of MMP1, -9, and -14 in MOCs, EpC, UM-SCC-22B, and FADUDD. DNA strand breaks (DNA-SBs) increased significantly at low pH and after incubation with human or artificial gastric juice. Single incubation with glycochenodeoxycholic acid also showed a significant increase in DNA-SBs. In epithelial cell cultures, human gastric juice increased the number of DNA-SBs at pH 4.5 and 5.5. Artificial gastric juice significantly up regulated the gene expression of MMP9. Western blot analysis confirmed the results of gene expression analysis, but the up regulation of MMP1, -9, and -14 was donor-specific. Reflux has the ability to promote genomic instability and may contribute to micro environmental changes suitable for the initiation of malignancy. Further functional gene analysis may elucidate the role of laryngopharyngeal reflux in the development of head neck squamous cell carcinoma (HNSCC).

Oesophageal hyperkeratosis: clinicopathological associations

AIMS

Oesophageal hyperkeratosis is rarely described. In contrast to hyperkeratosis of orolaryngeal mucosa, where its risk factors and association with squamous neoplasia are well-studied, the prevalence and clinicopathological features of oesophageal hyperkeratosis are unknown.

METHODS AND RESULTS

We reviewed prospectively 1845 oesophageal biopsies and found hyperkeratosis in 37 (2.0%). Among 98 patients studied, hyperkeratosis occurred in two distinct settings: group 1 [within Barrett's oesophagus (BO)/adenocarcinoma, n = 61, 62%] and group 2 (outside BO/adenocarcinoma, n = 37, 38%). In contrast to group 1, hyperkeratosis in group 2 was more often multifocal (>3 foci in 51% versus 16%, P = 0.0001), involved mid-oesophagus (51% versus 2%, P < 0.0001), showed endoscopic leucoplakia (24% versus 3%, P = 0.003) and involved current/former alcohol users (51% versus 19%, P = 0.0012). Importantly, invasive squamous carcinoma and squamous dysplasia were seen only in group 2 (47% and 19% versus 0%, P < 0.0001). Further, 42% of group 2, but none of group 1, had benign or malignant squamous lesions of the oral cavity/larynx (P < 0.0001).

CONCLUSION

Hyperkeratosis involves ~2% of oesophageal biopsies and can be divided into cases occurring within BO/adenocarcinoma and those occurring outside BO/adenocarcinoma. The former lack clinical significance, whereas the latter are associated frequently with oesophageal squamous neoplasia and squamous pathology of the head and neck region.

Relationship between reflux and laryngeal cancer

Gastroesophageal reflux disease (GERD), or its variation known as laryngopharyngeal reflux (LPR), has been recognized as a potential cause of several laryngeal disorders. Patients with laryngeal cancer have lifestyle risk factors, especially tobacco and alcohol consumption, that play an etiological role in the development of their cancer but also places them at risk for reflux. The question then arises whether there is merely an association or a causal relationship between laryngeal cancer and reflux. However, despite a number of studies, a causal relationship with laryngeal cancer is uncertain. In this article, we address the current literature in a critical manner to evaluate the relationship between reflux and laryngeal cancer. From the review of the literature, we conclude that there is insufficient evidence to support a causal role of reflux in laryngeal cancer, mainly because of the confounding effect of tobacco and alcohol consumption and the inaccuracies in the diagnosis of reflux.

Gastric reflux is an independent risk factor for laryngopharyngeal carcinoma

BACKGROUND

Gastric reflux can reach into the upper airway, inducing cellular damage in the epithelial lining. This condition is believed to be a risk factor for development of laryngopharyngeal squamous cell carcinoma (LPSCC), although the literature is conflicting.

METHODS

To better clarify this relationship, we assessed the association of self-reported heartburn history and medication use among 631 patients with LPSCCs and 1234 control subjects (frequency-matched on age, gender, and town of residence) enrolled as part of a population-based case-control study of head and neck squamous cell carcinoma in the greater Boston area.

RESULTS

After adjusting for age, gender, race, smoking, alcohol consumption, HPV16 seropositivity, education, and body mass index, subjects reporting a history of frequent heartburn and who were neither a heavy smoker nor heavy drinker had a significantly elevated risk of LPSCCs [OR, 1.78; 95% confidence interval (CI), 1.00-3.16]. Among those with a history of heartburn, there was an inverse association between antacid use and LPSCCs relative to those never taking heartburn medication (OR, 0.59; 95% CI, 0.38-0.93) that remained consistent when analyzed by smoking/drinking status, HPV16 status, or by primary tumor site.

CONCLUSIONS

Our data show that gastric reflux is an independent risk factor for squamous cancers of the pharynx and larynx. Further studies are needed to clarify the possible chemopreventive role of antacid use for patients with gastric reflux.

IMPACT

Elucidation of additional risk factors for head and neck cancer can allow for risk stratification and inform surveillance of high-risk patients.

The severity of duodeno-esophageal reflux influences the development of different histological types of esophageal cancer in a rat model

The mechanism through which each histological type of carcinoma arises from the esophageal mucosa remains unknown. This study was designed to investigate whether there is an association between the severity of duodeno-esophageal reflux and the histological type of esophageal cancer. A series of 120 male Fischer rats, weighing ∼180 g, were randomized to receive one of the following procedures: duodeno-forestomach reflux (DFR) with reduced exposure to duodenal contents, duodeno-esophageal reflux (DER) with increased exposure to duodenal contents and three control operations (DFR, DER control and sham). The reflux of bile was estimated with (99m)Tc-PMT scintigraphy. All animals were fed a standard diet without carcinogen. The esophageal mucosa was assessed 50 weeks after surgery for carcinoma. The median scanned fraction rate of duodeno-esophageal reflux was significantly lower for the rodents in the DFR group than those in the DER group. Five of 28 rodents in the DFR group and 17 of the 22 rodents in the DER group developed esophageal carcinoma. None of the controls developed carcinoma. The five rodents in the DFR group developed SCC. Of 22 esophageal carcinomas for the DER group, nine were SCC, 12 ADC and one was adenosquamous carcinoma. The fraction of esophageal SCC for the DFR group was significantly higher than that for the DER group, while the fraction of esophageal ADC for the DFR group was significantly lower than that for the DER group. These observations suggest that the severity of duodeno-esophageal reflux in rodents is related to the development of different histological types of esophageal carcinoma.

Pepsin promotes proliferation of laryngeal and pharyngeal epithelial cells

OBJECTIVE/HYPOTHESIS

Laryngopharyngeal reflux (LPR) is thought to be a significant risk factor for laryngeal squamous cell carcinoma (SCC), but causality has never been proven. It is accepted that chronic reflux into the esophagus can induce metaplastic changes in esophageal mucosa with subsequent increased risk of esophageal adenocarcinoma, but no similar associations have been established for LPR and laryngopharyngeal SCC. The objective of this study was to test the hypothesis that reflux of pepsin into the laryngopharynx can promote carcinogenesis.

STUDY DESIGN

Translational research study.

METHODS

Normal human laryngeal primary epithelial cell cultures and hypopharyngeal FaDu SCC cells were exposed to human pepsin and analyzed by Human Cancer PathwayFinder and miRNA Superarrays, flow cytometry, and Western blot to determine the effect of pepsin on carcinogenesis. Laryngeal biopsy specimens taken from cancer patients and normal control subjects were analyzed for the presence of pepsin by Western blot.

RESULTS

Microarray analysis demonstrated that pepsin significantly altered the expression of 27 genes implicated in carcinogenesis and also affected the expression of 22 microRNAs known to be altered in human head and neck cancers. Pepsin increased proliferation in both FaDu SCC cells and cultured normal laryngeal epithelial primary cells by increasing S phase distribution on flow cytometry analysis in a time- and dose-dependent manner. Furthermore, pepsin was detected in 60% (3/5) human laryngeal cancer biopsies, absent in all (0/5) normal control specimens.

CONCLUSIONS

These data support a role for refluxed pepsin in the promotion of epithelial proliferation and carcinogenesis of the larynx and pharynx.

Increased risk of laryngeal and pharyngeal cancer after gastrectomy for ulcer disease in a population-based cohort study

Background:

Gastrectomy has been indicated as a risk factor for laryngeal cancer, and possibly also for pharyngeal cancer, but few studies are available. The postulated mechanism is increased bile reflux following gastrectomy.

Methods:

This was a population-based cohort study of patients who underwent gastrectomy for peptic ulcer disease between 1964 and 2008 in Sweden. Follow-up data for cancer was obtained from the Swedish Cancer Register. Relative risk was calculated as standardised incidence ratios (SIRs) with 95% confidence intervals (CIs).

Results:

The gastrectomy cohort comprises 19 767 patients, contributing 348 231 person-years at risk. The observed number of patients with laryngeal (n=56) and pharyngeal cancer (n=28) was two-fold higher than the expected (SIR: 2.0, 95% CI: 1.5–2.6 and SIR: 2.4, 95% CI: 1.6–3.5, respectively). After exclusion of 5536 cohort members with tobacco- or alcohol-related disease, the point SIRs remained increased (SIR: 1.6, 95% CI: 1.1–2.2 and SIR: 1.7, 95% CI: 0.9–2.8, respectively). The SIRs of laryngeal and pharyngeal cancer increased with time after gastrectomy (P for trend <0.0001), and were particularly increased ⩾30 years after gastrectomy (SIR: 4.8, 95% CI: 2.1–9.5 and SIR: 10.2, 95% CI: 3.7–22.3, respectively).

Conclusion:

Gastrectomy for peptic ulcer disease might entail a long-term increased risk of laryngeal and pharyngeal cancer.

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.

Non-acid reflux: the missing link between gastric atrophy and esophageal squamous cell carcinoma?

Esophageal cancer is the eighth most common incident cancer in the world and, due to the poor survival rate it confers, ranks sixth among all cancers in mortality. In developed countries of the western world, the incidence of esophageal squamous cell carcinoma (ESCC) has undergone a decline and adenocarcinoma now constitutes approximately half of all esophageal cancers. In these relatively low-risk areas, tobacco smoking and alcohol consumption account for ~90% of ESCC cases. Eastern countries have much higher incidences of ESCC and epidemiologic evidence would suggest that there are additional unknown causal mechanisms. Gastric atrophy has consistently been associated with ESCC, but its causal relevance has been questioned. In this issue of the American Journal of Gastroenterology, Uno et al. offer evidence that a causal link between these two entities is non-acid reflux.

Is there any association between esophagogastric endoscopic findings and laryngeal cancer?

PURPOSE

The aim of the study was to survey the association between prevalence of acid-related inflammation in the upper digestive tract and laryngeal cancer.

MATERIALS AND METHODS

A case-control study was done in an otolaryngology ward at an academic university. Totally, 65 patients with laryngeal cancer and 65 cancer-free matched controls underwent esophagogastroduodenoscopy, and endoscopic findings were collected.

RESULTS

In the case group, positive endoscopic findings were significantly higher than the control group (87.7% vs 58.5%; P < .001). Laryngeal cancer patients had erosive esophagitis, and gastritis ± other findings more than the control group (48 vs 29 cases) and the difference was statistically significant.

CONCLUSION

The difference between endoscopic findings in cases and controls was statistically significant. Severe inflammation and erosion existed in patients with laryngeal cancer that could be due to increased acid secretion. Our study supported the hypothesis that gastric acid and pepsin play a role in laryngeal cancer.

Cholecystectomy and risk of laryngeal and pharyngeal cancer

Duodeno-gastro-esophageal reflux of bile might cause laryngeal and pharyngeal cancer, but more research is required. Since cholecystectomy is followed by an increased risk such reflux, the risk of developing laryngeal or pharyngeal cancer after cholecystectomy was addressed. A population-based cohort study was conducted in Sweden during the period 1965-2008. The number of laryngeal or pharyngeal cancer cases observed in a large cohort of cholecystectomized patients was compared with the expected number, calculated from the entire Swedish population of corresponding age, gender and calendar year. Risk of laryngeal or pharyngeal cancer was calculated as standardized incidence ratio (SIR) with 95% confidence interval (CI). The cholecystectomy cohort included 345,251 patients who were followed up for 1-43 years and contributed 4,854,969 person-years at risk. The 192 new cases of laryngeal cancer and the 175 cases of pharyngeal cancer were not greater than the expected, providing SIR 0.99 (95% CI 0.85-1.14) and SIR 1.06 (95% CI 0.91-1.23), respectively. A longer latency period after cholecystectomy was not associated with any increased risk of any of these tumors. No differences between age groups or sexes were detected. Analyses restricted to verified squamous-cell carcinomas revealed similar results. In conclusion, cholecystectomy does not appear to be followed by any increased risk of laryngeal or pharyngeal cancer.

The role of laryngopharyngeal reflux as a risk factor in laryngeal cancer: a preliminary report

Objectives

To evaluate the significance of laryngopharyngeal reflux (LPR) as a risk factor in laryngeal cancer.

Methods

We performed a case-control study with 29 consecutive laryngeal cancer patients who had undergone 24-hour ambulatory double pH monitoring from 2003 to 2006. The control group included 300 patients who had undergone 24-hour ambulatory double pH monitoring due to LPR-related symptoms. We analyzed the prevalence of LPR and numerous parameters from the 24-hour ambulatory double pH monitoring in the laryngeal cancer patient and control groups. Pathologic LPR is defined when more than three episodes of LPR occur in 24 hours.

Results

The prevalence of pathologic LPR was significantly higher in the laryngeal cancer group than the control group (P=0.049). The reflux number of the upper probe was significantly higher in the laryngeal cancer group (P<0.001). However the effects of pathologic LPR on laryngeal cancer risk were diluted after adjusting for smoking and alcohol consumption in the multivariable logistic regression.

Conclusion

The pathologic LPR might be a possible risk factor in the development of laryngeal cancer. A further study should be necessary to verify the exact role of LPR in laryngeal cancer.

Reevaluation of gastroesophageal reflux disease as a risk factor for laryngeal cancer

OBJECTIVES/HYPOTHESIS

The relationship between gastroesophageal reflux disease (GERD) and laryngeal cancer has not been fully elucidated. This case-control study investigates whether GERD increases the odds of developing these malignancies.

STUDY DESIGN

Case-control study.

METHODS

Rates of GERD among cases of laryngeal cancer identified in the Veterans Health Administration outpatient care files (year 2000-2006) were compared with controls. Cases (N = 14,449) were frequency matched 1:1 with controls. Multivariate logistic regression was used to determine the association between GERD and cancer.

RESULTS

After adjusting for tobacco and/or alcohol use, there was no association between GERD and laryngeal cancer (adjusted odds ratio, 1.01; 95% confidence interval, 0.92-1.12, P =.780). Although an association was found when time from GERD diagnosis to malignancy was less than 3 months, it disappeared when this period was extended further.

CONCLUSIONS

In this population, there was no increased risk of laryngeal cancer among patients with GERD. However, in subsite analysis, a possible relationship between GERD and glottic cancer was observed. Reverse causality must be considered in future studies assessing the relationship between reflux and laryngeal cancer to limit misclassification bias.

Serum pepsinogens and Helicobacter pylori in relation to the risk of esophageal squamous cell carcinoma in the alpha-tocopherol, beta-carotene cancer prevention study

BACKGROUND

Helicobacter pylori can induce gastric atrophy in humans, which in turn increases gastric cancer risk. Whether H. pylori and gastric atrophy also affect the risk of esophageal squamous cell carcinoma (ESCC), however, remains unresolved.

METHODS

We performed a nested case-control study within the prospective Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study to assess these relationships. The Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study is composed of 29,133 Finnish male smokers, ages 50 to 69 years, who were recruited during 1985-1988. Using baseline sera, we assessed H. pylori status (via immunoglobulin G antibodies against whole-cell and CagA antigens) and gastric atrophy status [via the biomarkers pepsinogen I (PGI) and pepsinogen II (PGII)] in 79 ESCC cases and 94 controls. Logistic regression with adjustment for age, date of blood draw, education, cigarette smoking, alcohol, body mass index, and fruit and vegetable intake was used to estimate odds ratios (OR) and 95% confidence intervals (95% CI).

RESULTS

Gastric atrophy (PGI/PGII <4) was associated with ESCC (OR, 4.58; 95% CI, 2.00-10.48). There was no evidence for an association between H. pylori and ESCC (OR, 0.94; 95% CI, 0.40-2.24).

CONCLUSIONS

These results could be explained by misclassification of H. pylori status due to serologic amnesia, ESCC risk being dependent on the functional consequences or interactions of H. pylori rather than the infection per se, gastric atrophy having a different histogenesis in ESCC without being primarily dependent on H. pylori acquisition, or a lack of statistical power to detect an effect.

IMPACT

Validation of these results may warrant mechanistic studies to determine the route of association between gastric atrophy and ESCC.

Is there a role for flexible oesophagogastroscopy in upper aerodigestive tract squamous cell carcinoma?

Introduction:

There is growing evidence to suggest that reflux (both laryngopharyngeal and gastroesophageal) has a role in the development of upper aerodigestive tract squamous cell carcinoma. This study discusses the role of identifying reflux in this patient group, and its prevalence.

Methods:

Prospective review of patients with head and neck cancer undergoing flexible oesophagogastroscopy as part of their diagnostic investigation.

Results:

Forty-five consecutive patients were identified. All patients were found to have evidence of oesophagitis, with 28 having oesophageal erosions and two Barrett's oesophagitis.

Conclusion:

Flexible oesophagogastroscopy is a useful test in patients with upper aerodigestive tract squamous cell carcinoma.

A selective cyclooxygenase-2 inhibitor prevents inflammation-related squamous cell carcinogenesis of the forestomach via duodenogastric reflux in rats

BACKGROUND

Duodenal reflux causes inflammation-related squamous cell carcinogenesis in the forestomach of rats without any carcinogens. The aim of this study was to investigate the efficacy of a selective cyclooxygenase (COX)-2 inhibitor, meloxicam, in preventing this carcinogenesis.

METHODS

A series of 188 rats underwent a surgical duodenogastric reflux procedure and were divided into 2 groups. One group was given commercial chow (control group), and the other was given experimental chow containing meloxicam (0.3 mg/kg body weight/day) (meloxicam group). The animals were sequentially sacrificed at Weeks 20, 30, 40, 50, and 60 after surgery. The forestomach was examined for the presence of carcinoma, the incidence of reflux-related morphological changes, COX-2 expression, and its activity.

RESULTS

At Week 60, squamous cell carcinoma developed in 8 of 21 animals (38%) in the control group, but none of 20 (0%) in the meloxicam group (P<.05). In addition, basal cell dysplasia developed in 19 of 21 (90%) animals in the control group, but only 4 of 20 (20%) in the meloxicam group (P<.01). COX-2 immunoreactivity was predominantly detected in macrophages in the epithelial stroma. Compared with nonsurgical rats, RNA expression of COX-2 in the epithelium was up-regulated, reaching peak at an early stage of Week 20 in both groups (P<.005). The expression of microsomal prostaglandin E synthase-1 was lower in the meloxicam group than in the control group. PGE2 production was significantly suppressed throughout the experiment in the meloxicam group compared with the control group (P<.005).

CONCLUSIONS

Meloxicam was effective in preventing reflux-induced squamous cell carcinogenesis via an inflamed squamous epithelium.

Association between Helicobacter pylori infection and laryngo-hypopharyngeal carcinoma: a case-control study and review of the literature

BACKGROUND

Gastroesophageal reflux, by exposing the pharynx to Helicobacter pylori (H. pylori), is a potential risk factor for laryngo-hypopharyngeal carcinoma. Its possible association has been inconsistent. In this case-control study, we investigated the relationship between H. pylori seropositivity and laryngo-hypopharyngeal carcinoma in Iran.

METHODS

We had 105 healthy controls (group A), 70 cases of laryngeal carcinoma (group B), and 28 cases of hypopharyngeal carcinoma group (group C). Age, sex, smoking habit, alcohol use, and H. pylori serology were determined for all subjects.

RESULTS

Groups were matched in age and alcohol use. Smoking and H. pylori seropositivity were more common in groups B and C, and male sex was more common in group B (compared with group A). In multivariate regression, the effect of smoking (p <.01, odds ratio [OR] = 2.92) and H. pylori seropositivity (p <.01, OR = 11.49) remained highly significant.

CONCLUSION

H. pylori is an independent risk factor for laryngo-hypopharyngeal carcinoma.

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.

Salivary glutathione and uric acid levels in patients with head and neck squamous cell carcinoma

BACKGROUND

We evaluated the concentrations of glutathione and uric acid, low molecular weight antioxidants, in saliva of patients with head and neck squamous cell carcinoma (HNSCC), in order to identify differences with normal subjects and to obtain information about biochemical alterations of human saliva during carcinogenesis.

METHODS

We compared 50 HNSCC patients, divided in 2 subsets on the basis of tumor site, with a control group of 77 subjects, without a previous diagnosis of HNSCC, matched for age, sex, alcohol consumption, and smoking status.

RESULTS

At tests for equality of means by Welch and Brown-Forsythe, differences between groups resulted probable for salivary levels of glutathione (p = .004 and p < .001 respectively) but not for salivary levels of uric acid (p = .228 and p = .122 respectively). Comparing groups by Tamhane test, the patients with oral or pharyngeal cancer had significantly higher salivary levels of glutathione than both controls and patients with laryngeal cancer.

CONCLUSIONS

Salivary glutathione levels may be an index of oxidative stress at the level of the upper airways and in particular of oral cavity and pharynx. Therefore, high salivary glutathione may be an epidemiological marker to identify subjects with an increased risk of developing HNSCC, to submit to strict follow-up and chemoprevention. Metabolic alterations of saliva could be both an epidemiological marker and a target for chemoprevention of oral and oropharyngeal carcinogenesis.