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

Does Extraesophageal Reflux Support the Development of Lung Adenocarcinoma? Analysis of Pepsin in Bronchoalveolar Lavage in Non-Smoker Patients

The significance of extraesophageal reflux as a risk factor in lung adenocarcinoma has been understudied. In this study, we investigated whether extraesophageal reflux leads to higher pepsin concentrations in bronchoalveolar lavage (BAL) in patients with lung adenocarcinoma compared to controls. Subjects were recruited from non-smoker patients (lifelong non-smokers and ex-smokers with more than 5 years of non-smoking history) who had undergone bronchoscopy due to pulmonary abnormalities on a CT scan and met the inclusion criteria. Based on histological verification of the lung process, the patients were divided into three groups: (1) lung adenocarcinoma, (2) pulmonary metastases, and (3) lung sarcoidosis. Lung adenocarcinoma cases were further categorized as central or peripheral. BAL samples collected during bronchoscopy were quantitatively analyzed by enzyme-linked immunosorbent assay (ELISA) to measure pepsin levels. No statistically significant difference in pepsin concentration was observed between the lung adenocarcinoma group and control groups (p = 0.135). After excluding hemorrhagic BAL samples, the pepsin concentration was significantly the lowest in patients with lung adenocarcinoma (p = 0.023) compared to the control groups. The results of the study do not support the hypothesis of a higher occurrence of extraesophageal reflux (evaluated as the amount of pepsin in BAL) in non-smoker patients with lung adenocarcinoma.

[Risk factors of recurrence and canceration for premalignant vocal fold lesions after surgery]

Objective:To analyze the risk factors of recurrence and canceration for premalignant vocal fold lesions after surgery, and to provide a reasonable basis for preoperative evaluation and postoperative follow-up. Methods:This study retrospective analyzed the relationship between clinicopathological factors and clinical outcome（recurrence, canceration, recurrence-free survival, and canceration-free survival） in 148 patients undergoing surgical treatment in Chongqing General Hospital from 2014 to 2017. Results:The five-year overall recurrence rate was 14.86% and the overall recurrence rate was 8.78%. Univariate analysis showed that smoking index, laryngopharyngeal reflux and lesion range were significantly associated with recurrence（P<0.05）, and smoking index and lesion range were significantly associated with canceration（P<0.05）. Multivariate logistic regression analysis showed that smoking index ≥600 and laryngopharyngeal reflux were independent risk factors for recurrence（P<0.05）, and smoking index ≥600 and lesion range ≥1/2 vocal cord were independent risk factors for canceration（P<0.05）. The mean carcinogenesis interval for the postoperative smoking cessation group was significantly longer（P<0.05）. Conclusion:Excessive smoking, laryngopharyngeal reflux and a wide range of lesions may be related to postoperative recurrence or malignant progression of precancerous lesions in the vocal cord, and further large-scale multi-center prospective randomized controlled studies are needed to clarify the effects of the above factors on recurrence and malignant changes in the future.

Oral and Inhaled Fosamprenavir Reverses Pepsin-Induced Damage in a Laryngopharyngeal Reflux Mouse Model

OBJECTIVE

More than 20% of the US population suffers from laryngopharyngeal reflux. Although dietary/lifestyle modifications and alginates provide benefit to some, there is no gold standard medical therapy. Increasing evidence suggests that pepsin is partly, if not wholly, responsible for damage and inflammation caused by laryngopharyngeal reflux. A treatment specifically targeting pepsin would be amenable to local, inhaled delivery, and could prove effective for endoscopic signs and symptoms associated with nonacid reflux. The aim herein was to identify small molecule inhibitors of pepsin and test their efficacy to prevent pepsin-mediated laryngeal damage in vivo.

METHODS

Drug and pepsin binding and inhibition were screened by high-throughput assays and crystallography. A mouse model of laryngopharyngeal reflux (mechanical laryngeal injury once weekly for 2 weeks and pH 7 solvent/pepsin instillation 3 days/week for 4 weeks) was provided inhibitor by gavage or aerosol (fosamprenavir or darunavir; 5 days/week for 4 weeks; n = 3). Larynges were collected for histopathologic analysis.

RESULTS

HIV protease inhibitors amprenavir, ritonavir, saquinavir, and darunavir bound and inhibited pepsin with IC50 in the low micromolar range. Gavage and aerosol fosamprenavir prevented pepsin-mediated laryngeal damage (i.e., reactive epithelia, increased intraepithelial inflammatory cells, and cell apoptosis). Darunavir gavage elicited mild reactivity and no discernable protection; aerosol protected against apoptosis.

CONCLUSIONS

Fosamprenavir and darunavir, FDA-approved therapies for HIV/AIDS, bind and inhibit pepsin, abrogating pepsin-mediated laryngeal damage in a laryngopharyngeal reflux mouse model. These drugs target a foreign virus, making them ideal to repurpose. Reformulation for local inhaled delivery could further improve outcomes and limit side effects.

LEVEL OF EVIDENCE

NA. Laryngoscope, 133:S1-S11, 2023.

HPV and head and neck cancers: Towards early diagnosis and prevention

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide with an increasing trend of its incidence. Alcohol consumption, smoking, and viral infections, such as the mucosal high-risk (HR) human papillomaviruses (HPVs) are major risk factors for HNSCC development. In particular, HR HPVs are mainly associated with a subset of oropharyngeal squamous cell carcinoma (OPSCC), while other head and neck sites are marginally affected by HPV infection. HPV16 is the most frequently HR HPV type associated with HNSCC. In contrast to the cervix, no screening programs or identifiable pre-malignant lesions have been characterized for HPV-related HNSCC. Therefore, identification of general diagnostic algorithms and HPV biomarkers that could facilitate the early diagnosis, disease evolution and recurrence for HPV-driven HNSCCs are urgently needed. We herein review the role of HPV in HNSCC with a focus on epidemiology, biology, applied diagnostic algorithms and available biomarkers in body fluids as early diagnostic tools in HPV-driven HNSCCs.

Prevalence of Laryngopharyngeal Reflux Disease in Indian Population

Laryngopharyngeal Reflux Disease (LPRD) is form of extra-oesophageal reflux due to the backflow of gastric contents into the upper aero digestive tract leading to throat symptoms. World over, the prevalence rate of LPRD, ranges from 5 to 30%. The aim of this study was to find the prevalence rate of LPRD in Indian population. This was an observational study whereby the RSI questionnaire was circulated amongst the population and records collected. All subjects who had RSI score more than 13 were considered to be suffering from LPRD. 2300 responses were collected from almost all strata of population. Out of 2300 people who responded 253 had RSI score > 13, and were considered as suffering from LPRD. Thus the prevalence rate of LPRD in population was 11%. The prevalence rate of LPRD in females was 11.2% and in males was 10.6%. The difference in prevalence among both the genders was not significant.The most common symptom of LPR reported by subjects was heartburn followed by clearing of throat and excess throat mucous. The prevalence of LPRD in Indian population as assessed by RSI score > 13 was 11%. The prevalence is same in males and females.

Laryngopharyngeal reflux: is laparoscopic fundoplication an effective treatment?

INTRODUCTION

Laryngopharyngeal reflux (LPR) is difficult to diagnose and treat owing to uncertainty relating to the underlying pathology. The initial management of LPR includes lifestyle modifications and oral medications. In patients who have failed to respond to proton pump inhibitor (PPI) therapy, anti-reflux surgery is considered; laparoscopic fundoplication is the surgery of choice. The primary aim of this review is to identify whether fundoplication is effective in improving signs and symptoms of LPR. The secondary aim is to identify whether patients who have had a poor response to PPIs are likely to have symptom improvement with surgery. The objective of the study is to establish the effect of laparoscopic fundoplication on the reflux symptom index score (RSI).

METHODS

PubMed, Embase, Medline and Cochrane databases were used to search according to the PRISMA guidelines. Original articles assessing the efficacy of fundoplication in relieving symptoms of LPR were included. For each study, the efficacy endpoints and safety outcomes were recorded.

FINDINGS

Nine studies from 844 initial records met the inclusion criteria: one prospective case control study, one retrospective case-control study, four prospective case series and three retrospective case series involving 287 fundoplications. All nine studies found fundoplication to be effective in improving symptoms of LPR (p < 0.05).

CONCLUSION

Current evidence suggests laparoscopic fundoplication is an effective treatment for LPR and should be considered if medical management is unsuccessful.

Aggravation of Reflux Finding Score (RFS) after thyroidectomy

Laryngopharyngeal reflux (LPR) has been suggested as a possible cause of post-thyroidectomy syndrome. However, the pathophysiology and relationship between thyroidectomy and LPR have not been well investigated. We aimed to evaluate the correlation between thyroidectomy and LPR by assessing changes in LPR-related symptoms and laryngoscopic findings before and after thyroidectomy. Ninety-five patients who underwent thyroidectomy with or without central neck dissection were included. The reflux finding score (RFS) and reflux symptom index (RSI) were investigated one day before surgery and two, four, six, and twelve months after surgery. The RFS scores increased significantly after thyroidectomy and decreased to the preoperative level 12 months after surgery. The RSI scores increased after surgery and decreased gradually by 12 months postoperatively, although it was not statistically significant. The RSI and RFS scores improved with the administration of proton pump inhibitors. In conclusion, LPR-related laryngoscopic findings were exacerbated after uncomplicated thyroidectomy. Further studies using pH-monitoring and esophageal manometry are required to investigate the possible deterioration of LPR itself and the UES pressure after thyroidectomy.

Gastroesophageal reflux disease: A risk factor for laryngeal squamous cell carcinoma and esophageal squamous cell carcinoma in the NIH-AARP Diet and Health Study cohort

BACKGROUND

Prior studies have suggested that gastroesophageal reflux disease (GERD) may be associated with risk of squamous cancers of the larynx and esophagus; however, most of these studies have had methodological limitations or insufficient control for potential confounders.

METHODS

We prospectively examined the association between GERD and esophageal adenocarcinoma (EADC), esophageal squamous cell carcinoma (ESCC), and laryngeal squamous cell carcinoma (LSCC) in 490,605 participants of the NIH-AARP Diet and Health Study cohort who were 50-71 years of age at baseline. Exposure to risk factors were obtained from the baseline questionnaire. GERD diagnosis was extracted among eligible participants via linkage to Medicare diagnoses codes and then multiply imputed for non-Medicare-eligible participants. Hazard ratios (HRs) and 95% CIs of GERD were computed using Cox regression.

RESULTS

From 1995 to 2011, we accrued 931 cases of EADC, 876 cases of LSCC, and 301 cases of ESCC in this cohort and estimated multivariable-adjusted HRs of 2.23 (95% CI, 1.72-2.90), 1.91 (95% CI, 1.24-2.94), and 1.99 (95% CI, 1.39-2.84) for EADC, LSCC, and ESCC, respectively. The associations were independent of sex, smoking status, alcohol intake, and follow-up time periods. We estimated that among the general population in the United States, 22.04% of people aged 50-71 years suffered from GERD. Using risk factor distributions for the United States from national survey data, 16.92% of LSCC cases and 17.32% of ESCC cases among individuals aged 50-71 years were estimated to be associated with GERD.

CONCLUSION

GERD is a common gastrointestinal disorder, but future prospective studies are needed to replicate our findings. If replicated, they may inform clinical surveillance of GERD patients and suggest new avenues for prevention of these malignancies.

Laryngeal Helicobacter pylori Infection and Laryngeal Cancer-Case Series and a Systematic Review

Helicobacter pylori (H. pylori) infection involves the development of gastric cancer and may be associated with laryngeal cancer. However, laryngeal H. pylori infection in Taiwanese patients with newly diagnosed laryngeal cancer has not been reported. This study was aimed to investigate the possible association between laryngeal H. pylori infection and laryngeal cancer in Taiwan and perform a systematic review of previous reports in other countries. An analysis of 105 patients with laryngeal lesions found the positive rates of H. pylori DNA (determined by polymerase chain reaction) and antigen (determined by immunohistochemistry) of the laryngeal lesions were relatively low (vocal polyps: 3% and 3%; vocal fold leukoplakia: 0% and 0%; laryngeal cancers: 0% and 2%). Furthermore, H. pylori-associated laryngopharyngeal reflux and the expression of E-cadherin and CD1d (determined by immunohistochemistry) were comparable among the three subgroups. Fifteen studies were involved in the systematic review of the digital literature database, distributed to February 2021. The data of patients with laryngeal cancer and controls showed that the laryngeal H. pylori infection rates were 29.4% and 16.7%, respectively. Although current evidence supported that laryngeal H. pylori infection was associated with laryngeal cancer globally, it might not play a role in the development of laryngeal cancer in Taiwan.

Presence of pepsin in laryngeal tissue and saliva in benign and malignant neoplasms

Objectives: The current study was performed to determine the presence of pepsin in saliva and laryngeal tissue among participants with benign and malignant laryngeal neoplasms.

Study design: Case–control study included three groups of patients with: (1) benign laryngeal neoplasms, (2) malignant laryngeal neoplasms and (3) control subjects without symptoms or signs of laryngopharyngeal reflux (LPR).

Methods: Eighty-one voluntary participants were included into study. They were recruited from a group of patients with histologically proven benign and malignant laryngeal neoplasms and in case of control subjects among patients with nasal septum deformation without symptoms of LPR.

Morning saliva samples were collected preoperatively. Tumor biopsies were collected by directoscopy of larynx and the control samples from interarytenoid unit of larynx. All samples were analyzed by Enzyme-Linked Immunosorbent Assay (ELISA) and Immunohistochemistry.

Results: Pepsin was found in all samples of saliva and tissue biopsies in groups with malignant and benign neoplasms. The highest concentration of pepsin was found in a group of patients with malignant laryngeal neoplasms. Patients with benign laryngeal neoplasms had lower concentrations and the control subjects presented with the lowest concentration of pepsin measured from their saliva. Differences were not statistically significant. Immunohistochemical (IHC) analysis showed the largest number of high positive samples in the group of malignant lesions.

Conclusion: These results suggest that pepsin and LPR can contribute to the development of benign and malignant laryngeal neoplasms. Further prospective studies, with far more patients, are necessary to prove the role of pepsin in multifactorial etiology of laryngeal neoplasms.

Gastric H+/K+-ATPase Expression in Normal Laryngeal Tissue and Laryngeal Carcinoma

Background

Several studies have suggested that laryngopharyngeal reflux disease (LPRD) or gastroesophageal reflux disease (GERD) is an independent risk factor for laryngeal carcinoma. However, it remains unclear whether either condition affects the level of H⁺/K⁺-ATPase expression in laryngeal carcinoma.

Materials and Methods

Immunohistochemistry, real-time RT-PCR, and Western blotting were used to explore the distributions of proton pump (H⁺/K⁺-ATPase) α- and β-subunits in normal laryngeal tissue and laryngeal carcinoma.

Results

Messenger RNAs encoding both the α- and β-subunits were found in the normal epiglottic, ventricular fold, vocal fold, and arytenoid mucosae, as well as epiglottic cartilage. The distributions and expression levels of H+/K+-ATPase α-subunits in various laryngeal subregions did not significantly differ in IHC, RT-PCR, or Western blotting. However, Western blotting revealed a significant difference between the expression level of the β-subunit protein in the epiglottic cartilage and the levels in other sites. The expression levels of both subunits were significantly higher in carcinomatous than in paracarcinomatous tissue and normal laryngeal tissue. The mean follow-up duration was 66.2 months (range, 17–162 months). In all, 4 patients died during follow-up, 4 were lost to follow-up, and 22 were alive and free of disease at the end of follow-up. Two patients developed lung metastases and six developed disease recurrences (at 2, 8, 14, 16, 36, and 41 months). The 3- and 5-year overall survival (OS) rates were 93.0% and 77.0%, respectively. Univariate analyses showed that the 5-year OSs were significantly associated with the T, N, and clinical stages but not with age, alcohol use, pathological differentiation, or the expression levels of the α- or β-subunits (as revealed by IHC, RT-PCR, or Western blotting). However, in multivariate regression analyses, the 5-year OSs were not significantly associated with any clinicopathological factor or the expression levels of either subunit.

Conclusion

H⁺/K⁺-ATPase is expressed in the normal larynx, including in the epiglottic cartilage and the mucosae of the epiglottis, ventricular fold, and arytenoid vocal fold. The expression levels of the H⁺/K⁺-ATPase α- and β-subunits in laryngeal carcinomas were higher than in normal laryngeal tissues.

Gastroesophageal reflux disease and head and neck cancers: A systematic review and meta-analysis

PURPOSE

Gastroesophageal reflux disease (GERD) has been associated with head and neck cancer (HNC), including laryngeal and pharyngeal anatomical sites. A systematic review and meta-analysis was performed to examine these associations.

METHODS

Articles were retrieved from the Medline, Web of Science, Scopus, and Embase databases using keywords "gastroesophageal reflux disease", "laryngopharyngeal reflux", "head and neck cancer", and associated variants. Inclusion criteria were English language publications, human subjects, and controlled studies with described development of head and neck cancer among individuals with GERD. 13 studies with a total of 39,824 patients were included.

RESULTS

Overall, presence of GERD was associated with an increased risk of developing HNC (OR = 1.86, 95% Confidence Interval [CI] = 1.27-2.74). This association remained significant with laryngeal cancers (OR = 1.95, 95% CI = 1.33-2.86), but not pharyngeal cancers (OR = 1.56, 95% CI = 0.86-2.83). Subgroup analyses of hypopharyngeal (OR = 2.26, 95% CI = 0.67-7.68) and oropharyngeal subsites (OR = 1.39, 95% CI = 0.51-3.84) were not statistically significant. Meta-analysis of studies that objectively assessed reflux, such as pH monitor placement, showed statistical significance (OR = 2.81, 95% CI = 1.36-5.81), while studies that used subjective reporting or chart review of GERD were not significant (OR = 1.46, 95% CI = 0.89-2.40). Association between H. pylori infection and head and neck cancers was not statistically significant (OR = 2.66, 95% CI = 0.59-11.97).

CONCLUSION

A diagnosis of GERD is associated with a later diagnosis of HNC, but this association is not significant for pharyngeal cancers. Associations of GERD with HNC may be specific to laryngeal cancers.

LEVEL OF EVIDENCE

Systematic review and meta-analysis of case control studies (3a).

Hiatal hernia repair and magnetic sphincter augmentation to treat laryngopharyngeal reflux aiding the prevention of recurrent laryngeal cancer

Laryngopharyngeal reflux (LPR) is a difficult disease to treat and can result in mucosal injury in the pharynx and larynx. This typically results in symptoms such as cough, hoarseness, and globus sensation, but the manifestation of cancer is a possibility. We present a patient with a squamous cell cancer of the larynx who was diagnosed with gastroesophageal reflux disease (GERD) and found to have LPR. The cancer was treated locally and GERD was eradicated with magnetic sphincter augmentation. After 15 months of follow-up, there was no residual cancer. This case highlights the role that untreated LPR may play in patients' risk of developing laryngeal cancer.

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.

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.

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.

Integrative analysis of mRNA and microRNA expression profiles in laryngeal squamous cell carcinoma

Larynx cancer is a therapeutically challenging disease. Rapidly evolving experimentally validated data have significantly improved our understanding of the complex role of numerous RNA, DNA, and proteins that play a role in the development and progression of cancer. Based on the insights from approximately two decades of research, it seems clear that microRNAs (miRNAs) have revolutionized our concepts related to the main role of noncoding RNAs in different cancers' progression, development, and metastasis. Mechanistically, miRNAs have been reported to regulate different RNAs and finally protein-coding genes. The expression profiling of miRNAs and messenger RNA (mRNAs) was conducted for a deeper analysis of the miRNAs and mRNAs which play an essential role in larynx cancer. Downregulation or upregulation over twofolds in the miRNAs was considered to be significant, and that of sixfolds or below was considered to be significant for the mRNAs. In accordance with this approach, the expression levels of 43 miRNAs were increased in this study, whereas the expression levels of 129 were decreased. Accordingly, all the genomic expression studies provided evidence of upregulation of 97 genes, whereas 128 genes were found to be downregulated. Among these miRNAs, hsa-miR-20a-3p and hsa-miR-1972 were noted to be important in the etiology of larynx 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.

Sympathetic Nerve Entrapment Point Injection as an Antireflux Procedure for Refractory Laryngopharyngeal Reflux: A First Case Report of Innovative Autonomic Regulation

Surgical treatment is not suitable for laryngopharyngeal reflux that is refractory to proton pump inhibitors. We present a case of proton pump inhibitor-refractory laryngopharyngeal reflux that was successfully treated with sympathetic nerve entrapment point injection. The patient had previously been diagnosed with laryngopharyngeal reflux and treated with proton pump inhibitors for six months without substantial improvement. After sympathetic nerve entrapment point injection treatment, her reflux symptom index improved from 15 points to 1 point, and this response was maintained for six months. Hyperexcitability of T5 and T6 sympathetic preganglionic fibers appears to be the main cause of laryngopharyngeal reflux. Sympathetic nerve entrapment point injection may represent an alternative to anti-reflux procedures.

Xanthohumol inhibits proliferation of laryngeal squamous cell carcinoma

Xanthohumol is a flavonoid compound that exhibits antioxidant and anticancer effects, and is used to treat atherosclerosis. The aim of the present study was to investigate the effect of xanthohumol on the cell proliferation of laryngeal squamous cell carcinoma and to understand the mechanism of its action. The effects of xanthohumol on the cell viability and apoptosis rate of laryngeal squamous cell carcinoma SCC4 cells were assessed by Annexin V-fluorescein isothiocyanate/propidium iodide staining. In addition, the expression levels of pro-apoptotic proteins, caspase-3, caspase-8, caspase-9, poly ADP ribose polymerase (PARP) p53 and apoptosis-inducing factor (AIF), as well as anti-apoptotic markers, B-cell lymphoma 2 (Bcl-2) and myeloid cell leukemia 1 (Mcl-1), were analyzed by western blotting. The results revealed that treatment with 40 µM xanthohumol significantly inhibited the proliferation of SCC4 cells. Furthermore, xanthohumol treatment (40 µM) induced SCC4 cell apoptosis, as indicated by the significant increase in activity and expression of caspase-3, caspase-8, caspase-9, PARP, p53 and AIF. By contrast, the protein expression of Bcl-2 and Mcl-1 was significantly decreased following treatment with 40 µM xanthohumol. Taken together, the results of the present study indicated that xanthohumol mediates growth suppression and apoptosis induction, which was mediated via the suppression of Bcl-2 and Mcl-1 and activation of PARP, p53 and AIF signaling pathways. Therefore, future studies that investigate xanthohumol as a potential therapeutic agent for laryngeal squamous cell carcinoma are required.

Proton pump inhibitors and histamine 2 blockers are associated with improved overall survival in patients with head and neck squamous carcinoma

It has been postulated that gastroesophageal reflux plays a role in the etiology of head and neck squamous cell carcinomas (HNSCC) and contributes to complications after surgery or during radiotherapy. Antacid medications are commonly used in patients with HNSCC for the management of acid reflux; however, their relationship with outcomes has not been well studied. Associations between histamine receptor-2 antagonists (H2RA) and proton pump inhibitors (PPI) use and treatment outcomes were determined in 596 patients with previously untreated HNSCC enrolled in our SPORE epidemiology program from 2003 to 2008 (median follow-up 55 months). Comprehensive clinical information was entered prospectively in our database. Risk strata were created on the basis of possible confounding prognostic variables (age, demographics, socioeconomics, tumor stage, primary site, smoking status, HPV16 status, and treatment modality); correlations within risk strata were analyzed in a multivariable model. Patients taking antacid medications had significantly better overall survival (OS; PPI alone: P < 0.001; H2RA alone, P = 0.0479; both PPI + H2RA, P = 0.0133). Using multivariable Cox models and adjusting for significant prognostic covariates, both PPIs and H2RAs used were significant prognostic factors for OS, but only H2RAs use for recurrence-free survival in HPV16-positive oropharyngeal patients. We found significant associations between the use of H2RAs and PPIs, alone or in combination, and various clinical characteristics. The findings in this large cohort study indicate that routine use of antacid medications may have significant therapeutic benefit in patients with HNSCC. The reasons for this association remain an active area of investigation and could lead to identification of new treatment and prevention approaches with agents that have minimal toxicities.

Higher levels of total pepsin and bile acids in the saliva as a possible risk factor for early laryngeal cancer

Background

Gastroesophageal reflux is suspected to be an etiological factor in laryngeal and pharyngeal cancer. The aim of this study was to establish, using a non-invasive method, whether laryngopharyngeal reflux (LPR) appears more often in patients with early laryngeal cancer than in a control group.

Patients and methods

We compared the pH, the level of bile acids, the total pepsin and the pepsin enzymatic activity in saliva in a group of 30 patients with T1 laryngeal carcinoma and a group of 34 healthy volunteers.

Results

The groups differed significantly in terms of levels of total pepsin and bile acids in the saliva sample. Higher levels of total pepsin and bile acids were detected in the group of cancer patients. No significant impact of other known factors influencing laryngeal mucosa (e.g. smoking, alcohol consumption, and the presence of irritating substances in the workplace) on the results of saliva analysis was found.

Conclusions

A higher level of typical components of LPR in the saliva of patients with early laryngeal cancer than in the controls suggests the possibility that LPR, especially biliary reflux, has a role in the development of laryngeal carcinoma.

Establishment of an immortalized laryngeal posterior commissure cell line as a tool for reflux research

OBJECTIVES/HYPOTHESIS

Laryngopharyngeal reflux (LPR) has been implicated as a promoter of laryngeal cancer. Within the larynx, the posterior commissure (PC) is the region that usually comes into direct contact with refluxed materials. Specific laryngeal cell lines useful for in vitro studies are not widely available, and noncancer-derived PC laryngeal cell line has not yet been described.

STUDY DESIGN

Experimental study.

METHODS

Specimens of squamous epithelium from the PC of the larynx were collected from patients without a history or evidence of laryngeal inflammatory or neoplastic diseases. Harvested tissue was cultured and then immortalized by transduction with human papillomavirus E6/E7-encoding lentivirus. PC primary and transformed cells were characterized by light microscopy and immunohistochemistry.

RESULTS

Primary cultures established from PC contained < 5% fibroblasts and displayed normal epithelial cell morphology and cytokeratin expression. These cells survived nine passages in culture. Following lentiviral-mediated immortalization, cells retained normal squamous epithelial morphology and survived > 20 passages in culture. Methods were optimized for culture of PC laryngeal epithelial cells, resulting in 90% success rate of culture.

CONCLUSION

A novel immortalized PC laryngeal epithelial cell line has been established. This cell line provides a unique tool for investigating the mechanism of LPR in the development and progression of laryngeal cancer.

LEVEL OF EVIDENCE

N/A.

Chronic pepsin exposure promotes anchorage-independent growth and migration of a hypopharyngeal squamous cell line

OUTCOME OBJECTIVES

(1) Investigate the role of reflux, specifically pepsin, in laryngopharyngeal carcinogenesis. (2) Evaluate effects of chronic pepsin exposure on cell migration, apoptosis, and colony-forming ability in hypopharyngeal cells.

STUDY DESIGN

Translation research.

SETTING

Academic research laboratory.

METHODS

Human hypopharyngeal squamous carcinoma FaDu cells were chronically exposed to nonacidic pepsin (exposed for 24 hours, 4 times over 2 weeks at the following concentrations: 0.01 mg/mL, 0.1 mg/mL, or 1 mg/mL). Precise wounds were created in confluent cell plates, and rates of cell migration into wounds were quantified. Separately, cell viability of chronic pepsin-exposed FaDu cells acutely treated with paclitaxel was measured. Finally, a clonogenic assay was performed on these cells to measure effects of chronic pepsin exposure on colony-forming ability.

RESULTS

An increased rate of relative wound density was observed in chronic pepsin-treated (0.01 mg/mL, 0.1 mg/mL) cells compared with control (P < .001), suggesting greater rates of cell migration. Pepsin-treated (0.1 mg/mL) cells demonstrated on average greater cell viability compared with control after exposure to paclitaxel, suggesting possible apoptotic resistance; however, this was not statistically significant. Chronic pepsin exposure (0.1 mg/mL, 1 mg/mL) was associated with a dose-dependent increase in colony-forming ability relative to control (P < .001).

CONCLUSION

Hypopharyngeal squamous cell line chronically exposed to pepsin demonstrated increased cell migration and colony-forming ability relative to control cells. These experiments indicate that chronic pepsin exposure acts as a promoter of tumorigenesis and metastasis of airway epithelium, suggesting a role for pepsin in laryngopharyngeal carcinogenesis attributed to gastric reflux.

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.

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).

Expression of HMGA1 and ezrin in laryngeal squamous cell carcinoma

CONCLUSION

The overexpression of HMGA1 or Ezrin may contribute to the carcinogenesis, development, and metastasis of laryngeal squamous cell carcinoma (LSCC).

OBJECTIVE

To investigate the expression of HMGA1 and Ezrin in LSCC and analyze their clinical significance.

METHODS

The expression of HMGA1 and Ezrin was analyzed by immunohistochemistry (IHC) in 50 cases of LSCC. Thirty cases of laryngeal polyp and 30 cases of atypical hyperplasia of larynx were studied as controls. The expression of HMGA1 and Ezrin was analyzed by real-time PCR and by Western blot in 30 cases of LSCC; samples from adjacent normal epithelial tissues in 30 cases were studied as controls.

RESULTS

(1) IHC revealed that the positive rate of HMGA1 protein was 68.0% (34/50), 53.3% (16/30), and 13. 3% (4/30) in LSCC, atypical hyperplasia of larynx, and laryngeal polyp (p < 0.05), and the positive rate of Ezrin protein was 64.0% (32/50), 50.0% (15/30), and 23.3% (7/30) (p < 0.01), respectively. (2) Real-time PCR demonstrated that the mean relative mRNA expression levels of HMGA1 in LSCC and in normal tissues were 2.41 ± 0.40 and 1.05 ± 0.18, respectively (p < 0.01). The mRNA levels of Ezrin in LSCC and in normal tissues were 1.79 ± 0.27 and 1.04 ± 0.22, respectively (p < 0.05). (3) Western blotting revealed that the mean relative protein expression levels of HMGA1 in LSCC and in normal tissues were 1.73 ± 0.60 and 0.35 ± 0.17, respectively (p < 0.01). The protein levels of Ezrin in LSCC and in normal tissues were 1.82 ± 0.77 and 0.42 ± 0.20, respectively (p < 0.01).

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.

First agreement analysis and day-to-day comparison of pharyngeal pH monitoring with pH/impedance monitoring in patients with suspected laryngopharyngeal reflux

OBJECTIVE

Diagnosis of laryngopharyngeal reflux (LPR) is still challenging. Recently a diagnostic device for pH values in the aerosolized environment of the pharynx has been introduced (Dx-pH). We evaluated results of Dx-pH with objective criteria of pH/impedance monitoring (MII) and subjective reflux scoring systems and assessed day-to-day variability.

DESIGN

This study makes use of a prospective single-center trial. Thirty patients with suspected LPR were analyzed. Upper endoscopic examination, manometry, phoniatric examination, and reflux scores were assessed. Dx-pH was performed on two consecutive days, first in combination with MII and second as single measurement. Thereafter, proton pump inhibitor (PPI) trial was performed. Patients were interviewed about symptom relief after 3 months.

RESULTS

There were considerable differences between MII and results on Dx-pH: day 1 (agreement 11 out of 30, kappa 0.137) and day 2 (agreement 14 out of 30, kappa 0.036). Statistically significant differences were detected correlating all single reflux episodes (n = 453) of Dx-pH with MII and vice versa. Furthermore acidic reflux episodes did not result in pH drops of the pharynx. There was a fair agreement between Dx-pH measurements on subsequent days. After follow-up, 3 out of 18 patients with pathological Dx-pH results reported positive response to PPIs, in contrast to 5 out of 6 patients with pathological MII.

CONCLUSION

According to our data, acid pharyngeal pH levels detected with Dx-pH are not related to GERD and acid esophageal reflux episodes do not result in pharyngeal pH alterations. Hence, present etiology of LPR needs to be reconsidered since neither mixed nor gas reflux events result in pharyngeal pH alteration. Other acid-producing or retaining factors should be taken into account.