Association of laryngeal cancer with previous gastric resection

Reduction of head and neck cancer risk following smoking cessation: a systematic review and meta-analysis

OBJECTIVE

Head and neck (HN) cancer comprises the neoplasms originating from the oral cavity, pharynx and larynx. We aimed at reviewing the available literature on the effect of smoking cessation on HN cancer risk.

METHOD

We conducted a systematic search in Medline, PubMed and Embase to June 2022. We abstracted or calculated relative risks (RR) and 95% CIs of HN cancer after cessation of tobacco smoking (both former smoking status and duration of quitting) and combined them using random effects meta-analyses. Papers included were case-control or cohort studies available in the English language. Studies investigating smoking cessation after cancer diagnosis, case reports, intervention studies or animal studies were excluded. Quality and susceptibility to bias of each included study were evaluated using the Newcastle-Ottawa Scale. Publication bias was assessed using funnel plot and Egger's test.

RESULTS

A total of 65 studies were included in the review, including 5 cohort and 60 case-control studies. The RR of HN cancer for former smokers compared with current smokers was 0.40 (95% CI 0.35 to 0.46). In an analysis by cancer site, the RR of oral cancer was 0.44 (95% CI 0.35 to 0.55), that of pharyngeal cancer 0.44 (95% CI 0.32 to 0.60) and that of laryngeal cancer 0.38 (95% CI 0.29 to 0.50). The dose-response meta-analysis was based on 37 studies. The RR per 10-year increase in smoking cessation was 0.47 (95% CI 0.43 to 0.52).

CONCLUSIONS

The risk of HN cancer declines within the first 5 years of quitting smoking. Quitting smoking is an essential element of HN cancer prevention.

TRIAL REGISTRATION NUMBER

The protocol has been deposited in the PROSPERO repository (CRD42022338262).

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.

RNA Sequencing Reveals Cancer-Associated Changes in Laryngeal Cells Exposed to Non-Acid Pepsin

OBJECTIVE

Laryngopharyngeal reflux (LPR) is a common affliction that contributes to laryngeal inflammation, symptoms that impact quality of life, and life-threatening illnesses such as cancer. Effective treatment strategies for LPR are lacking. Pepsin is a proinflammatory and carcinogenic element of refluxate. Investigation of molecular pathways involved in pepsin-mediated damage may lead to identification of novel biomarkers and therapeutic targets for LPR. In this study, RNA sequencing was used to examine changes in human laryngeal epithelial cells following brief pepsin insult. Cells were immortalized to generate a model to aid future study of laryngeal injury and therapeutics.

STUDY DESIGN

In vitro translational.

METHODS

Laryngeal epithelial cells were cultured from a patient without signs or symptoms of LPR or laryngeal cancer. Cells were treated with 0.1 mg/ml pepsin for 1 hour or normal growth media (control) prior to RNA sequencing. Cells were immortalized via HPV E6/7 and characterized by microscopy, immunohistochemistry, G-banding, and soft agar assay.

RESULTS

Three hundred ninety-seven genes exhibited differences in expression with pepsin treatment (P < .05). Pathway analysis revealed association with cancer and related signaling processes including dysregulation of cancer-associated molecules, Metastasis-Associated Lung Adenocarcinoma Transcript 1 and KRT82, and the long-noncoding RNA, lipoprotein receptor-related protein 1 (LRP1)-AS, which regulates the putative pepsin receptor LRP1.

CONCLUSIONS

A single, brief exposure to pepsin activated cancer-associated signaling pathways in laryngeal cells in vitro, revealing novel mechanisms by which chronic reflux may contribute to carcinogenesis. The cell line developed herein represents a novel tool in which to investigate pepsin-dysregulated pathways identified by RNA sequencing and disparities of tumor proneness of laryngeal subsites.

LEVEL OF EVIDENCE

N/A Laryngoscope, 131:121-129, 2021.

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.

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.

Gastroesophageal Reflux Disease and Aerodigestive Disorders

This relationship between gastroesophageal reflux and airway disorders is complex, possibly bidirectional, and not clearly defined. The tools used to investigate gastroesophageal reflux are mostly informative about involvement of gastroesophageal reflux within the gastrointestinal tract, although they are often utilized to study the relationship between gastroesophageal reflux and airway issues with are suspected to occur in relation to reflux. These modalities often lack specificity for reflux-related airway disorders. Co-incidence of gastroesophageal reflux and airway disorders does not necessarily infer causality. While much of our focus has been on managing acidity, controlling refluxate is an area that has not been traditionally aggressively pursued. Our management approach is based on some of the evidence presented, but also often from a lack of adequate study to provide further guidance.

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.

Laryngopharyngeal reflux and GERD

In patients with laryngopharygeal reflux (LPR), gastric contents exhibit retrograde flow into the upper aero-digestive tract, causing extraesophageal symptoms including chronic cough, hoarseness, indigestion, difficulty swallowing, globus pharyngis, and asthma. The following on laryngopharyngeal reflux includes commentaries on the use of patient-completed questionaires and anti-human pepsin antibodies and other non-invasive tests in diagnosis; the role of pepsin and acid in the etiologies of laryngeal cancers; and the application of proton pump inhibitor (PPI) therapy for the treatment of LPR.

Helicobacter pylori infection of the larynx may be an emerging risk factor for laryngeal squamous cell carcinoma

INTRODUCTION

Several studies have implicated Helicobacter pylori as a risk factor in laryngeal cancer, but other studies disagree. It is fundamental that the relationship between Helicobacter pylori and laryngeal cancer be verified in order to provide evidence of ways to prevent the initiation and development of this carcinoma.

MATERIALS AND METHODS

In total, 81 patients with laryngeal squamous cell carcinoma and 75 control subjects were enrolled in a case-control study. Semi-nested polymerase chain reaction techniques were applied to detect Helicobacter pylori in the laryngeal mucosa and enzyme-linked immunosorbent assays were used to detect serum antibodies against Helicobacter pylori. Risk factors associated with laryngeal carcinoma were analyzed using logistic regression models.

RESULTS

The presence of Helicobacter pylori in the larynx was higher in patients with laryngeal cancer than in control subjects (71.6 vs. 25.3 %, p < 0.001). Among patients with laryngeal carcinoma, rates of Helicobacter pylori infection were higher in normal laryngeal tissues than in tumor tissues. After adjusting for confounding factors, regression analysis indicated that the microbe was an independent risk factor for laryngeal cancer (OR = 7.15, 95 % CI [3.29, 15.53], p < 0.001).

CONCLUSIONS

This study suggests that Helicobacter pylori is present in the mucosa of the larynx. The microorganism may be an independent risk factor for laryngeal squamous cell carcinoma. The laryngeal mucosa thus provides a reservoir for the bacteria possibly, and is a likely staging place for its transmission to other areas.

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.

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.

Clinical symptoms of esophageal intraepithelial neoplasia: an analysis of 101 cases

AIM: To analyze the clinical symptoms of esophageal intraepithelial neoplasia (EIN), their frequency, and relationship with disease location.

METHODS: One hundred and one patients with EIN treated by endoscopic mucosal resection (EMR) from January 2009 to December 2009 at the Affiliated Nanjing Drum Tower Hospital of Medical School of Nanjing University were enrolled in this study. The patients were given questionnaires to fill in the gastroesophageal symptoms they experienced. The data were then analyzed.

RESULTS: The study population consists of 71 men and 30 women. Of all the patients, 41.58% (42/101) had symptoms of sour regurgitation and belching, 27.72% (28/101) had substernal pain, and 2.97% (3/101) had no symptoms. The frequency of these symptoms is 2-3 d per week. The pathological results after endoscopic mucosal resection showed that 35 patients had high-grade intraepithelial neoplasia, 54 had low-grade intraepithelial neoplasia, and 12 had cancer. More patients with intraepithelial neoplasia in the middle of the esophagus had reflux symptoms than those with the lesions in the upper one third and lower one third of the esophagus (P < 0.001).

CONCLUSION: The majority of patients with EIN have reflux symptoms. The incidence of symptoms is related to the location of EIN. For patients with the above symptoms, comprehensive endoscopic and pathological examinations should be performed.

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.

Gastroesophageal reflux leads to esophageal cancer in a surgical model with mice

BACKGROUND

Esophago-gastroduodenal anastomosis with rats mimics the development of human Barrett's esophagus and esophageal adenocarcinoma by introducing mixed reflux of gastric and duodenal contents into the esophagus. However, use of this rat model for mechanistic and chemopreventive studies is limited due to lack of genetically modified rat strains. Therefore, a mouse model of esophageal adenocarcinoma is needed.

METHODS

We performed reflux surgery on wild-type, p53A135V transgenic, and INK4a/Arf+/- mice of A/J strain. Some mice were also treated with omeprazole (1,400 ppm in diet), iron (50 mg/kg/m, i.p.), or gastrectomy plus iron. Mouse esophagi were harvested at 20, 40 or 80 weeks after surgery for histopathological analysis.

RESULTS

At week 20, we observed metaplasia in wild-type mice (5%, 1/20) and p53A135V mice (5.3%, 1/19). At week 40, metaplasia was found in wild-type mice (16.2%, 6/37), p53A135V mice (4.8%, 2/42), and wild-type mice also receiving gastrectomy and iron (6.7%, 1/15). Esophageal squamous cell carcinoma developed in INK4a/Arf+/- mice (7.1%, 1/14), and wild-type mice receiving gastrectomy and iron (21.4%, 3/14). Among 13 wild-type mice which were given iron from week 40 to 80, twelve (92.3%) developed squamous cell carcinoma at week 80. None of these mice developed esophageal adenocarcinoma.

CONCLUSION

Surgically induced gastroesophageal reflux produced esophageal squamous cell carcinoma, but not esophageal adenocarcinoma, in mice. Dominant negative p53 mutation, heterozygous loss of INK4a/Arf, antacid treatment, iron supplementation, or gastrectomy failed to promote esophageal adenocarcinoma in these mice. Further studies are needed in order to develop a mouse model of esophageal adenocarcinoma.

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.

Bile acids and total bilirubin detection in saliva of patients submitted to gastric surgery and in particular to subtotal Billroth II resection

OBJECTIVE

The aim of our study was to detect bile acids and total bilirubin in saliva of gastrectomized patients, to confirm objectively presence of biliary laryngopharyngeal reflux and its relationship with laryngeal mucosa damage.

SUMMARY BACKGROUND DATA

Recently, it has been hypothesized that biliary-reflux may reach the upper aerodigestive tract and enhance development of laryngeal malignancies; nevertheless, the presence of duodenogastric contents in this region has never been revealed.

METHODS

We carried out a prospective observational case-control study on 52 patients (cases) previously submitted to gastric surgery, mainly to subtotal Billroth II resection, and on 51 healthy volunteers (controls). Patients were submitted to clinical interview, esophagogastroduodenal endoscopy, endoscopic laryngeal evaluation, and saliva collection. In all saliva samples, bile acids, total bilirubin, and pepsinogen II were assayed.

RESULTS

In cases, group bile acids levels were recorded in 17 of 52 (32.6%) patients, while in 35 of 52 (67.4%) they were undetectable. All controls were negative to bile acids. In positive cases to bile acids, we found a significant (P < 0.05) correlation between bile acids, total bilirubin, and pepsinogen II values and a significant (P < 0.05) higher prevalence of symptoms and findings of laryngeal damage and of previous laryngeal neoplastic lesions.

CONCLUSIONS

We found detectable levels of bile acids and total bilirubin in saliva of patients submitted to previous gastric surgery, prospecting an intriguing diagnostic role of this dosage in the study of biliary laryngopharyngeal reflux. We finally revealed a high incidence of laryngeal disorders in patients with positive bile acids in saliva.

Do acid and bile reflux into the esophagus simultaneously? Temporal relationship between duodenogastro-esophageal reflux and esophageal pH

BACKGROUND

Duodenogastro-esophageal reflux (DGER) is an important factor in the pathogenesis of reflux esophagitis. Animal studies have demonstrated that the injurious effect of duodenal juice components depends on pH. The purpose of the present study was to investigate the temporal relationship between DGER and esophageal pH.

METHODS

Seventy-six children with symptoms of gastro-esophageal reflux disease (27 without, 31 with mild, 18 with severe esophagitis) underwent 24 h simultaneous esophageal pH and bilirubin monitoring with Bilitec 2000. The recordings were analyzed for (i) pH at the beginning of DGER episodes; (ii) relative duration of DGER in eight defined pH intervals of 1 pH unit; and (iii) differences in relative duration of DGER between the three groups of children.

RESULTS

DGER episodes most frequently began at pH between 6 and 7. DGER was present in the esophagus across the spectrum of esophageal pH, with the biggest relative duration between pH 3 and 5. However, in children without esophagitis relative duration of DGER was longest between pH 5 and 6, in children with mild esophagitis between pH 4 and 5, while in those with severe esophagitis it was between pH 2 and 4 (P < 0.001).

CONCLUSIONS

DGER appears across the whole esophageal pH spectrum. The more severe the esophagitis, the lower the pH at which DGER occurs, resulting in simultaneous damaging effects of acid and duodenal juice components.

Laryngeal carcinoma and laryngo-pharyngeal reflux disease

A correlation between laryngo-pharyngeal reflux and laryngeal carcinoma is currently debated. Chronic inflammation is a mutagen factor confirmed in the cancerogenesis of various tumours. Aim of the present study was to evaluate, in an objective and consecutive way, with 24h multi-electrode pH-metry the presence of proximal and distal oesophageal reflux in patients presenting pre-cancerosis or squamous cell laryngeal and/or pharyngeal carcinomas. From our data, a strict correlation emerged between laryngo-pharyngeal reflux and neoplasias of the upper airways, documented through multi-electrode pH-metry. Data emerging from this study would seem to support the theory that the protracted exposure (> 20 years) to biliary reflux would represent a statistically significant added risk factor in the precancerous lesions and squamous pharyngo-laryngeal carcinoma as it occurs at oesophageal level. Moreover, a significant statistical association (p < 0.0001) emerged between laryngeal carcinoma and previous gastro-resection (odds ratio 3.8).

Biliary laryngopharyngeal reflux: a new pathological entity

PURPOSE OF REVIEW

The purpose of this review is to summarize the recent understanding of the harmful effects of gastric and duodenal agents on mucosa of the upper aerodigestive tract in patients with duodeno-gastro-esophageal reflux.

RECENT FINDINGS

The damaging action of duodeno-gastro-esophageal reflux on the gastro-esophageal mucosa and its potential etiological role in the development of many inflammatory and neoplastic patterns have been well documented in the literature. Recently, there has been increasing evidence that duodeno-gastro-esophageal reflux may also be related to several laryngeal disorders and clinical studies confirm that reflux after gastric resection may enhance the development of laryngeal malignancies. Finally, there have been experimental attempts to confirm that duodenal contents may contribute to inflammation and carcinogenesis in the pharynx or larynx, as it is known to do in the esophagus.

SUMMARY

The association between duodeno-gastro-esophageal reflux and laryngeal lesions is of great interest to otolaryngologists because it focuses attention on a new pathological entity that could be classified as biliary laryngopharyngeal reflux. This condition, as an acid one, seems to represent an important dangerous, endogenous risk factor involved in the pathogenesis of inflammatory, precancerous and neoplastic laryngeal lesions. For these reasons, particular attention is required in the future regarding the understanding of the local environment, individual susceptibility and clinical treatment. Finally, new antireflux therapy should be considered to control not only the acid gastric component of the refluxate but also the duodenal component.