Cost-effectiveness landscape analysis of treatments addressing xerostomia in patients receiving head and neck radiation therapy

Impact of low-level laser therapy on the quality of life of patients with xerostomia undergoing head and neck radiotherapy: a systematic review

PURPOSE

To carry out a systematic review to assess whether low-level laser therapy can improve the quality of life of patients with xerostomia undergoing head and neck radiotherapy.

METHODS

A systematic search was performed through Embase, Medline/PubMed, Cochrane, Scopus, Web of Science, nonpeer-reviewed clinicaltrials.gov and LILACS. The strategy included clinical studies were selected that prospectively followed or evaluated the quality of life by directly comparing the use of low-level laser therapy for xerostomia induced by head and neck radiotherapy with alternative therapies without the use of a laser. The risk of bias in the studies was assessed by RoB 2.0 and Robins I.

RESULTS

After all application of the predetermined criteria, four studies were included, dated between the years 2014 and 2023. Three studies described as randomized clinical trials were included, one of which was a randomized pilot study and only one was a prospective clinical trial. A total of 126 patients were evaluated, all four studies used the infrared wavelength, with two studies using the combination with the red wavelength. It was observed that low-level laser therapy can change the sensation of dry mouth, improving patients' quality of life. In addition, changes related to increased stimulated and unstimulated salivary flow were also identified.

CONCLUSION

The use of low-level laser therapy has promising results on xerostomia, consequently improving the quality of life of patients undergoing radiotherapy in the head and neck region.

Evaluation and management of dry mouth and its complications in rheumatology practice

INTRODUCTION

The symptom of dry mouth has multiple potential etiologies and can be a diagnostic clue to the presence of common systemic diseases encountered in rheumatology practice. The presence of decreased saliva flow (i.e. salivary hypofunction) defines a subset of dry mouth patients in whom there may be reversible drug effects, an iatrogenic insult such as head and neck irradiation, or a disease that directly involves the salivary glands (e.g. Sjögren's disease). The assessment of salivary hypofunction includes sialometry, salivary gland imaging, salivary gland biopsy, and an assessment for relevant systemic diseases. Optimal management of dry mouth requires accurate definition of its cause, followed by general measures that serve to alleviate its symptoms and prevent its complications.

AREAS COVERED

Through a literature search on xerostomia and salivary hypofunction, we provide an overview of the causes of dry mouth, highlight the potential impact of salivary hypofunction on oral and systemic health, detail routine evaluation methods and treatment strategies, and emphasize the importance of collaboration with oral health care providers.

EXPERT OPINION

Our Expert Opinion is provided on unmet needs in the management of dry mouth and relevant research progress in the field.

Salivary Gland Bioengineering

Salivary gland dysfunction affects millions globally, and tissue engineering may provide a promising therapeutic avenue. This review delves into the current state of salivary gland tissue engineering research, starting with a study of normal salivary gland development and function. It discusses the impact of fibrosis and cellular senescence on salivary gland pathologies. A diverse range of cells suitable for tissue engineering including cell lines, primary salivary gland cells, and stem cells are examined. Moreover, the paper explores various supportive biomaterials and scaffold fabrication methodologies that enhance salivary gland cell survival, differentiation, and engraftment. Innovative engineering strategies for the improvement of vascularization, innervation, and engraftment of engineered salivary gland tissue, including bioprinting, microfluidic hydrogels, mesh electronics, and nanoparticles, are also evaluated. This review underscores the promising potential of this research field for the treatment of salivary gland dysfunction and suggests directions for future exploration.

Basement Membrane Mimetic Hydrogel Cooperates with Rho-Associated Protein Kinase Inhibitor to Promote the Development of Acini-Like Salivary Gland Spheroids

Successful engineering of functional salivary glands necessitates the creation of cell-instructive environments for ex vivo expansion and lineage specification of primary human salivary gland stem cells (hS/PCs). Herein, basement membrane mimetic hydrogels were prepared using hyaluronic acid, cell adhesive peptides, and hyperbranched polyglycerol (HPG), with or without sulfate groups, to produce "hyperGel+" or "hyperGel", respectively. Differential scanning fluorescence experiments confirmed the ability of the sulphated HPG precursor to stabilize fibroblast growth factor 10. The hydrogels were nanoporous, cytocompatibile and cell-permissive, enabling the development of multicellular hS/PC spheroids in 14 days. Incorporation of sulfated HPG species in the hydrogel enhanced cell proliferation. Culture of hS/PCs in hyperGel+ in the presence of a Rho kinase inhibitor, Y-27632 (Y-27), led to the development of spheroids with a central lumen, increased the expression of acinar marker aquaporin-3 at the transcript level (AQP3), and decreased the expression of ductal marker keratin 7 at both the transcript (KRT7) and the protein levels (K7). Reduced expression of transforming growth factor beta (TGF-β) targets SMAD2/3 was also observed in Y27-treated cultures, suggesting attenuation of TGF-β signaling. Thus, hyperGel+ cooperates with the ROCK inhibitor to promote the development of lumened spheroids with enhanced expression of acinar markers.

AMPK Activation Restores Salivary Function Following Radiation Treatment

Head and neck cancers represent a significant portion of cancer diagnoses, with head and neck cancer incidence increasing in some parts of the world. Typical treatment of early-stage head and neck cancers includes either surgery or radiotherapy; however, advanced cases often require surgery followed by radiation and chemotherapy. Salivary gland damage following radiotherapy leads to severe and chronic hypofunction with decreased salivary output, xerostomia, impaired ability to chew and swallow, increased risk of developing oral mucositis, and malnutrition. There is currently no standard of care for radiation-induced salivary gland dysfunction, and treatment is often limited to palliative treatment that provides only temporary relief. Adenosine monophosphate (AMP)-activated protein kinase (AMPK) is an enzyme that activates catabolic processes and has been shown to influence the cell cycle, proliferation, and autophagy. In the present study, we found that radiation (IR) treatment decreases tissue levels of phosphorylated AMPK following radiation and decreases intracellular NAD+ and AMP while increasing intracellular adenosine triphosphate. Furthermore, expression of sirtuin 1 (SIRT1) and nicotinamide phosphoribosyl transferase (NAMPT) was lower 5 d following IR. Treatment with AMPK activators, 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR) and metformin, attenuated compensatory proliferation (days 6, 7, and 30) following IR and reversed chronic (day 30) salivary gland dysfunction post-IR. In addition, treatment with metformin or AICAR increased markers of apical/basolateral polarity (phosphorylated aPKCζT560-positive area) and differentiation (amylase-positive area) within irradiated parotid glands to levels similar to untreated controls. Taken together, these data suggest that AMPK may be a novel therapeutic target for treatment of radiation-induced salivary damage.

Quality of Life and Aesthetic Satisfaction in Patients Who Underwent the “Commando Operation” with Pectoralis Major Myocutaneus Flap Reconstruction—A Case Series Study

The “commando operation” is an extensive surgical procedure used to treat patients with oral squamous carcinoma and metastasis in the cervical lymph nodes. While the procedure can be curative, it is also very mutilating, which consequently has a major impact on the patient’s quality of life. Several studies showed that the procedure is associated with loss of certain functions, such as impairments in speech, chewing, swallowing, and loss of taste and appetite. Furthermore, some of these impairments and their degree depend on the reconstruction method. However, the data regarding the functional impairments and aesthetic results in patients who underwent the “commando operation” along with the pectoralis major myocutaneus flap reconstruction are still inconclusive. This study included 34 patients that underwent partial glossectomy, ipsilateral modified radical neck dissection, pectoralis major myocutaneus flap reconstruction, and adjuvant radiotherapy. A structured questionnaire was used to evaluate aesthetical results and functional impairments as well as to grade the level of satisfaction with the functional and aesthetic outcomes both by the patients and by the operator. Most of the patients stated that their speech (N = 33; 97%) and salivation (N = 32; 94.2%) severely changed after the operation and that they cannot chew (N = 33; 97%) and swallow (N = 33; 97%) the same as before the operation. Moreover, almost half of the patients (N = 16; 47%) reported that they have severe sleep impairments. However, only few of the included patients stated that they sought professional help regarding the speech (N = 4; 11.7%), eating (N = 5; 14.7%), and sleeping (N = 4; 11.7%) disturbances. Additionally, there was a statistically significant difference between the operator and the patients in the subjective assessment of the aesthetic results (p = 0.047), as operators gave significantly better grades. Our results imply that this procedure and reconstructive method possibly cause impairments that have an impact on the patients’ wellbeing. Moreover, our outcomes also suggest that patients should be educated and rehabilitated after the “commando operation” since most of them were reluctant to seek professional help regarding their impairments. Lastly, sleep deficiency, which was observed after the procedure, should be further explored.

Aldehyde dehydrogenase 3A1 deficiency leads to mitochondrial dysfunction and impacts salivary gland stem cell phenotype

Adult salivary stem/progenitor cells (SSPC) have an intrinsic property to self-renew in order to maintain tissue architecture and homeostasis. Adult salivary glands have been documented to harbor SSPC, which have been shown to play a vital role in the regeneration of the glandular structures postradiation damage. We have previously demonstrated that activation of aldehyde dehydrogenase 3A1 (ALDH3A1) after radiation reduced aldehyde accumulation in SSPC, leading to less apoptosis and improved salivary function. We subsequently found that sustained pharmacological ALDH3A1 activation is critical to enhance regeneration of murine submandibular gland after radiation damage. Further investigation shows that ALDH3A1 function is crucial for SSPC self-renewal and survival even in the absence of radiation stress. Salivary glands from Aldh3a1 -/- mice have fewer acinar structures than wildtype mice. ALDH3A1 deletion or pharmacological inhibition in SSPC leads to a decrease in mitochondrial DNA copy number, lower expression of mitochondrial specific genes and proteins, structural abnormalities, lower membrane potential, and reduced cellular respiration. Loss or inhibition of ALDH3A1 also elevates ROS levels, depletes glutathione pool, and accumulates ALDH3A1 substrate 4-hydroxynonenal (4-HNE, a lipid peroxidation product), leading to decreased survival of murine SSPC that can be rescued by treatment with 4-HNE specific carbonyl scavengers. Our data indicate that ALDH3A1 activity protects mitochondrial function and is important for the regeneration activity of SSPC. This knowledge will help to guide our translational strategy of applying ALDH3A1 activators in the clinic to prevent radiation-related hyposalivation in head and neck cancer patients.

A Computational Text Mining-Guided Meta-Analysis Approach to Identify Potential Xerostomia Drug Targets

Xerostomia (subjective complaint of dry mouth) is commonly associated with salivary gland hypofunction. Molecular mechanisms associated with xerostomia pathobiology are poorly understood, thus hampering drug development. Our objectives were to (i) use text-mining tools to investigate xerostomia and dry mouth concepts, (ii) identify associated molecular interactions involving genes as candidate drug targets, and (iii) determine how drugs currently used in clinical trials may impact these genes and associated pathways. PubMed and PubMed Central were used to identify search terms associated with xerostomia and/or dry mouth. Search terms were queried in pubmed2ensembl. Protein–protein interaction (PPI) networks were determined using the gene/protein network visualization program search tool for recurring instances of neighboring genes (STRING). A similar program, Cytoscape, was used to determine PPIs of overlapping gene sets. The drug–gene interaction database (DGIdb) and the clinicaltrials.gov database were used to identify potential drug targets from the xerostomia/dry mouth PPI gene set. We identified 64 search terms in common between xerostomia and dry mouth. STRING confirmed PPIs between identified genes (CL = 0.90). Cytoscape analysis determined 58 shared genes, with cytokine–cytokine receptor interaction representing the most significant pathway (p = 1.29 × 10⁻²³) found in the Kyoto encyclopedia of genes and genomes (KEGG). Fifty-four genes in common had drug interactions, per DGIdb analysis. Eighteen drugs, targeting the xerostomia/dry mouth PPI network, have been evaluated for xerostomia, head and neck cancer oral complications, and Sjögren’s Syndrome. The PPI network genes IL6R, EGFR, NFKB1, MPO, and TNFSF13B constitute a possible biomarker signature of xerostomia. Validation of the candidate biomarkers is necessary to better stratify patients at the genetic and molecular levels to facilitate drug development or to monitor response to treatment.

The relationship between the severity of oral dryness and the use of dry-mouth interventions by various subgroups of dry-mouth patients

OBJECTIVE

Dry-mouth patients use different interventions to relieve their oral dryness. As recent studies showed that various subgroups of dry-mouth patients perceived different intra-oral regions as most dry, the present study investigated whether the use of dry-mouth interventions by various subgroups of dry-mouth patients was related to the perceived oral dryness as well as salivary flow rate.

MATERIALS AND METHODS

Xerostomia Inventory (XI) scores, Regional Oral Dryness Score (RODI) scores and used dry-mouth interventions were extracted from the medical records of 528 patients visiting a saliva clinic. Based on their medical history, they were allocated into 6 subgroups.

RESULTS

The subgroups of dry-mouth patients used a wide range of interventions to relieve their oral dryness. Sjögren's syndrome patients used most interventions more frequently than patients with oral dryness due to use of a limited number of medications and controls. Patients using medications showed associations between the total XI score and dry-mouth interventions aimed at the entire mouth. In medication using patients and controls, the locally applied intervention "using mouth gel" was associated with RODI scores of the anterior tongue.

CONCLUSION

The use of dry-mouth interventions was associated with dry-mouth feelings. Use of interventions aimed to relieve dryness of the entire mouth was significantly associated with total XI score, while locally applied interventions were significantly associated with the severity of dryness at specific intra-oral regions, the anterior tongue in particular.

CLINICAL RELEVANCE

The results will help clinicians to advise dry-mouth patients about the most suitable interventions for relief of oral dryness complaints.

Salivary Gland Hypofunction and/or Xerostomia Induced by Nonsurgical Cancer Therapies: ISOO/MASCC/ASCO Guideline

PURPOSE

To provide evidence-based recommendations for prevention and management of salivary gland hypofunction and xerostomia induced by nonsurgical cancer therapies.

METHODS

Multinational Association of Supportive Care in Cancer/International Society of Oral Oncology (MASCC/ISOO) and ASCO convened a multidisciplinary Expert Panel to evaluate the evidence and formulate recommendations. PubMed, EMBASE, and Cochrane Library were searched for randomized controlled trials published between January 2009 and June 2020. The guideline also incorporated two previous systematic reviews conducted by MASCC/ISOO, which included studies published from 1990 through 2008.

RESULTS

A total of 58 publications were identified: 46 addressed preventive interventions and 12 addressed therapeutic interventions. A majority of the evidence focused on the setting of radiation therapy for head and neck cancer. For the prevention of salivary gland hypofunction and/or xerostomia in patients with head and neck cancer, there is high-quality evidence for tissue-sparing radiation modalities. Evidence is weaker or insufficient for other interventions. For the management of salivary gland hypofunction and/or xerostomia, intermediate-quality evidence supports the use of topical mucosal lubricants, saliva substitutes, and agents that stimulate the salivary reflex.

RECOMMENDATIONS

For patients who receive radiation therapy for head and neck cancer, tissue-sparing radiation modalities should be used when possible to reduce the risk of salivary gland hypofunction and xerostomia. Other risk-reducing interventions that may be offered during radiation therapy for head and neck cancer include bethanechol and acupuncture. For patients who develop salivary gland hypofunction and/or xerostomia, interventions include topical mucosal lubricants, saliva substitutes, and sugar-free lozenges or chewing gum. For patients with head and neck cancer, oral pilocarpine and oral cevimeline, acupuncture, or transcutaneous electrostimulation may be offered after radiation therapy.Additional information can be found at www.asco.org/supportive-care-guidelines.

Cost-effectiveness Analysis of Submandibular Gland Preservation With Sialendoscopy for the Management of Sialolithiasis

OBJECTIVE

To compare the cost-effectiveness of sialendoscopy with gland excision for the management of submandibular gland sialolithiasis.

STUDY DESIGN

Cost-effectiveness analysis.

SETTING

Outpatient surgery centers.

METHODS

A Markov decision model compared the cost-effectiveness of sialendoscopy versus gland excision for managing submandibular gland sialolithiasis. Surgical outcome probabilities were found in the primary literature. The quality of life of patients was represented by health utilities, and costs were estimated from a third-party payer's perspective. The effectiveness of each intervention was measured in quality-adjusted life-years (QALYs). The incremental costs and effectiveness of each intervention were compared, and a willingness-to-pay ratio of $150,000 per QALY was considered cost-effective. One-way, multivariate, and probabilistic sensitivity analyses were performed to challenge model conclusions.

RESULTS

Over 10 years, sialendoscopy yielded 9.00 QALYs at an average cost of $8306, while gland excision produced 8.94 QALYs at an average cost of $6103. The ICER for sialendoscopy was $36,717 per QALY gained, making sialendoscopy cost-effective by our best estimates. The model was sensitive to the probability of success and the cost of sialendoscopy. Sialendoscopy must meet a probability-of-success threshold of 0.61 (61%) and cost ≤$11,996 to remain cost-effective. A Monte Carlo simulation revealed sialendoscopy to be cost-effective 60% of the time.

CONCLUSION

Sialendoscopy appears to be a cost-effective management strategy for sialolithiasis of the submandibular gland when certain thresholds are maintained. Further studies elucidating the clinical factors that determine successful sialendoscopy may be aided by these thresholds as well as future comparisons of novel technology.

Duration of effect of Biotène spray in patients with symptomatic dry mouth: A pilot study

OBJECTIVES

The objective of this study was to assess the duration of effect of a single dose of Biotène Moisturizing Spray on xerostomia compared to water spray.

STUDY DESIGN

This double-blind randomized controlled crossover trial compared the duration of effect of 2 agents on relieving xerostomia in adult patients recruited through convenience sampling. Following a xerostomia questionnaire, qualifying patients with an unstimulated whole saliva flow rate of ≤0.20 mL/min rated their baseline level of discomfort from oral dryness and received a single dose (3 sprays) of Biotène Moisturizing Spray or water (active control). Patients indicated their level of oral discomfort every 15 min and the precise time when relief ceased. After a minimum 48-h washout, patients repeated the exercise with the alternative product.

RESULTS

The baseline severity of discomfort from oral dryness among qualifying patients was significantly related to their level of hyposalivation (P = .001). The mean duration of effect of Biotène Moisturizing Spray was 27 ± 25 min, which was not significantly different from that for water (26 ± 25 min; P = .88; n = 25).

CONCLUSION

Biotène Moisturizing Spray and water spray had variable durations of effect averaging approximately 30 min. The results of this pilot study provide guidance regarding anticipated usage and dispensing needs for patients with objective xerostomia. ClinicalTrials.gov NCT03663231.

Evaluation of the salivary function of patients in treatment with radiotherapy for head and neck cancer submitted to photobiomodulation

Background

Head and neck radiotherapy is typically associated with toxicities that can have profound effects on the patient's quality of life. Xerostomia, which may or may not be related to hypofunction of the salivary gland, leading to negative consequences, mainly in quality of life, leaving patients more susceptible to the development of oral mucositis, dental caries, oral infection and difficulties in speech is one of the most common side effects of such treatment. The aim of the present study was to evaluate salivary function of patients in treatment with radiotherapy for head and neck cancer submitted to photobiomodulation.

Material and Methods

A cross-sectional study with a quantitative approach was carried out in the Dentistry Department of the Hospital de Câncer de Pernambuco between February and September 2019.

Results

The study sample comprised 23 patients of both genders, treated with radiotherapy for cancer in the head and neck region. The patients were submitted to photobiomodulation with infrared laser, as intraoral applications in order to prevent mucositis and extraoral applications to stimulate salivary glands. The applications were undertaken three times a week on alternate days throughout the radiotherapy period. The following parameters were used: Intraoral 15mW, 12J / cm2, 10s / point, 2.4 J / point, and extraoral 30mW, 7.5J / cm2, 10s / point, 0.3J / point, both with a wavelength of 830nm and area of 0.028cm². Subjective and objective symptoms were evaluated by measuring the unstimulated salivary flow (USF) using the spitting technique before, during and after radiotherapy treatment. For statistical analysis, a significance level of 5% was adopted. Most patients were male (70%) with 60 years of age on average. At the beginning of treatment, 22 patients had USF> 0.2 ml / min (grade 1), at the end of which 15 patients remained unchanged and only 3 patients progressed to grade 3. As for the subjective classification, most (52%) remained in grade 1 (absence of disability) throughout the treatment.

Conclusions

Based upon the results of this study it was possible to conclude that the use of photobiomodulation did not significantly interfere with the xerostomia complaint of patients in treatment with radiotherapy, however, it does seem to prevent patients from reaching higher degrees of xerostomia taking into account salivary flow measures.

Key words:Photobiomodulation, head and neck neoplasms, radiotherapy, xerostomia, saliva.

Building a Functional Salivary Gland for Cell-Based Therapy: More than Secretory Epithelial Acini

A few treatment options exist for patients experiencing xerostomia due to hyposalivation that occurs as a result of disease or injury to the gland. An opportunity for a permanent solution lies in the field of salivary gland replacement through tissue engineering. Recent success emboldens in the vision of producing a tissue-engineered salivary gland composed of differentiated salivary epithelial cells that are able to differentiate to form functional units that produce and deliver saliva to the oral cavity. This vision is augmented by advances in understanding cellular mechanisms that guide branching morphogenesis and salivary epithelial cell polarization in both acinar and ductal structures. Growth factors and other guidance cues introduced into engineered constructs help to develop a more complex glandular structure that seeks to mimic native salivary gland tissue. This review describes the separate epithelial phenotypes that make up the gland, and it describes their relationship with the other cell types such as nerve and vasculature that surround them. The review is organized around the links between the native components that form and contribute to various aspects of salivary gland development, structure, and function and how this information can drive the design of functional tissue-engineered constructs. In addition, we discuss the attributes of various biomaterials commonly used to drive function and form in engineered constructs. The review also contains a current description of the state-of-the-art of the field, including successes and challenges in creating materials for preclinical testing in animal models. The ability to integrate biomolecular cues in combination with a range of materials opens the door to the design of increasingly complex salivary gland structures that, once accomplished, can lead to breakthroughs in other fields of tissue engineering of epithelial-based exocrine glands or oral tissues.

Acute and cumulative benefits of Photobiomodulation for xerostomia: A systematic review and meta-analysis

The objective was to explore the effectiveness of photobiomodulation therapy for treating patients who suffer xerostomia and/or hyposalivation due to the most prevalent clinical diagnoses. We searched PubMed, Scopus, Web of Science, CINAHL and Cochrane Library for randomized or clinical controlled trials published until 31 October 2019. Risk of bias assessment and meta-analysis were conducted using the Cochrane tools. A total of 274 records were retrieved, and 11 met the inclusion criteria. Interventions whose parameters ranged between wavelengths of 790-830 nm (infrared), 30-120 mW of power and an energy density below 30 J/cm-2 were associated with improvements in xerostomia/hyposalivation. As for the assessment of methodological quality, 10 of the 11 articles included had a high risk of overall bias. Only 3 articles provided sufficient information to conduct a meta-analysis for quality of life, compared with placebo in patients with burning mouth syndrome, showing a standardized mean difference between groups from baseline of -0.90 (-1.48; -0.32). The present review and meta-analysis suggest that photobiomodulation therapy is an effective, non-invasive and safe approach in patients with xerostomia. However, despite the potential, it is not possible to reach a reliable consensus on the parameters to be used, and future studies should be conducted by standardizing intervention protocols.

Where Dysphagia Begins: Polypharmacy and Xerostomia

BACKGROUND

Xerostomia, the subjective sensation of dry mouth, contributes to dysarthria, dysphagia, and diminished quality of life. Polypharmacy is a known and modifiable risk factor for xerostomia. The objective of this study was to evaluate the prevalence of dry mouth, the relationship between dry mouth and other oral conditions, and the impact of polypharmacy on dry mouth.

METHODS

This study was a retrospective cross-sectional study of all patients seen in fiscal year (FY) 2015 (October 1, 2014 to September 30, 2015) at the VA Palo Alto Health Care System (VAPAHCS), a tertiary care US Department of Veterans Affairs (VA) hospital. Patients diagnosed with xerostomia were identified using ICD-9 codes (527.7, 527.8, R68.2) and Systemized Nomenclature of Medicine Clinical Terms (SNOMED CT) codes (87715008, 78948009).

RESULTS

Of all the patients seen at VAPAHCS during FY 2015, 138 had a diagnostic code for xerostomia; of those patients, 84 had at least 1 documented speech, dentition, or swallowing (SDS) problem, and 55 (39.9%) were taking ≥ 12 medications, more than twice as many patients as in any one of the other groups studied (0-2, 3-5, 6-8, and 9-11 medications taken). Although 4,971 total patients seen at VAPAHCS had documented SDS problems during FY 2015, of those patients only 77 (1.5%) had an additional recorded diagnosis of xerostomia.

CONCLUSIONS

Heightened physician awareness regarding the signs and symptoms of and risk factors for xerostomia is needed to improve health care providers' ability to diagnose dry mouth. Polypharmacy also must be considered when developing new strategies for preventing and treating xerostomia.

Current alternatives in the prevention and treatment of xerostomia in cancer therapy

ABSTRACT In the last decades, there has been a substantial increase in the occurrence of cancer. The most commonly used treatment for this disease involves surgery, radiotherapy and chemotherapy. These treatment modalities are associated with different kinds of side effects, acute or late. Xerostomia is one of the main oral complications that affect patients undergoing antineoplastic treatments, mainly head and neck cancer patients. It is characterized by a “dry mouth” sensation resulting from decreased salivary flow. It is persistent and affects the integrity of oral tissues, thereby significantly affecting patients’ quality of life. Many strategies have been applied and others developed to prevent and reduce xerostomia. Accordingly, the objective of this study was to review the literature about current prevention and treatment measures aimed at improving the quality of life of xerostomic patients.

Patient-related outcomes in Sjögren syndrome treated with stimulants of salivary secretion: Randomized clinical trial

OBJECTIVES

To investigate the impact of gustatory stimulants of salivary secretion (GSSS) on Sjögren's syndrome patients' self-perception of xerostomia, oral health-related quality of life (OHRQoL) and salivary secretion.

METHODS

A total of 110 Sjögren's syndrome patients were randomly allocated to be treated with either a malic acid lozenge or a citric acid mouthwash and then crossed over. Before and after the interventions, the Xerostomia Inventory 5 (SXI-5-PL) and the Oral Health Impact Profile (OHIP-14-PT) questionnaires (both in the Portuguese language) were administered to patients. Unstimulated, mechanical and gustatory-stimulated salivary flows were determined. Repeated measures and between-subject analyses were performed. Statistical significance was set at 5%.

RESULTS

After the intervention and within each group, both GSSS elicited a reduction in the SXI-5-PL and OHIP-14-PT scores and an increase in salivary output, significant in the malic acid lozenge group. The malic acid treatment resulted in a greater effect size and percentage improvement than citric acid mouthwash. The malic acid lozenge also produced a significant greater salivary output than the citric acid rising solution.

CONCLUSIONS

In Sjögren's syndrome patients, lozenges containing malic acid increased saliva production and xerostomia relief, resulting in improved quality of life.

Impact of xerostomia on the quality of life of patients submitted to head and neck radiotherapy

Background

The aim of the present work was to evaluate the impact of xerostomia on the quality of life of patients who underwent radiotherapy in the head and neck region.

Material and Methods

This was a cross-sectional, quantitative study. The sample comprised 40 patients whose xerostomia was classified through the xerostomia inventory and the quality of life evaluated through the oral health impact profile questionnaire (OHIP).

Results

The majority of participants were male (75%), mean age 58.7 years. According to the degree of severity of the xerostomia, the average score among the participants was 36 points, this being considered moderate xerostomia. A significant impact was observed, with the median score 11 points, with the highest scores in the domains related to functional limitation, physical pain and physical disability. The majority of the participants (97.5%) had reduced salivary flow after the end of radiotherapy. There was a significant positive correlation between the degree of xerostomia and reduced quality of life, Pearson correlation 0.5421, (p< 0.05).

Conclusions

Based upon the results it is concluded that xerostomia has a negative impact on the quality of life of patients who undergo radiotherapy in the head and neck region.

Key words:Head and neck neoplasms, radiotherapy, xerostomia, quality of life.

Artificial Saliva: Challenges and Future Perspectives for the Treatment of Xerostomia

The chronic sensation of a dry mouth is a disease condition called xerostomia and affects a large part of the population. Xerostomia is associated with decreased secretion, or more often, qualitative changes in saliva proteins and immunoglobulin concentrations that develop as a result of salivary gland dysfunction. Several reasons causing dry mouth were described, and usually, they include taking medications, diseases or radiotherapy. In some situations, when it is difficult to use salivary stimulants or salivary gland damage is irreversible, the only option might seem to be saliva substitutes. The paper presents the most important aspects considering saliva preparations. The rheological and lubricating properties and the reconstruction of the complex saliva structure has been the main purpose of research. The biological properties of saliva preparations were also widely discussed. As part of the work, the antimicrobial effect of three commercial saliva preparations was tested. Finally, inadequate antimicrobial properties against the strains isolated from the oral cavity were demonstrated. The development of salivary substitutes, in particular, the improvement of antimicrobial properties, can be achieved using nanotechnology, including drug delivery systems containing nanocarriers.

RDH10-mediated retinol metabolism and RARα-mediated retinoic acid signaling are required for submandibular salivary gland initiation

In mammals, the epithelial tissues of major salivary glands generate saliva and drain it into the oral cavity. For submandibular salivary glands (SMGs), the epithelial tissues arise during embryogenesis from naïve oral ectoderm adjacent to the base of the tongue, which begins to thicken, express SOX9 and invaginate into underlying mesenchyme. The developmental mechanisms initiating salivary gland development remain unexplored. In this study, we show that retinoic acid (RA) signaling activity at the site of gland initiation is colocalized with expression of retinol metabolic genes Rdh10 and Aldh1a2 in the underlying SMG mesenchyme. Utilizing a novel ex vivo assay for SMG initiation developed for this study, we show that RDH10 and RA are required for salivary gland initiation. Moreover, we show that the requirement for RA in gland initiation involves canonical signaling through retinoic acid receptors (RAR). Finally, we show that RA signaling essential for gland initiation is transduced specifically through RARα, with no contribution from other RAR isoforms. This is the first study to identify a molecular signal regulating mammalian salivary gland initiation.

A systematic review of the effects of acupuncture on xerostomia and hyposalivation

BACKGROUND

Saliva is fundamental to our oral health and our well-being. Many factors can impair saliva secretion, such as adverse effects of prescribed medication, auto-immune diseases (for example Sjögren's syndrome) and radiotherapy for head and neck cancers. Several studies have suggested a positive effect of acupuncture on oral dryness.

METHODS

Pubmed and Web of Science were electronically searched. Reference lists of the included studies and relevant reviews were manually searched. Studies that met the inclusion criteria were systematically evaluated. Two reviewers assessed each of the included studies to confirm eligibility and assessing the risk of bias.

RESULTS

Ten randomized controlled trials investigating the effect of acupuncture were included. Five trials compared acupuncture to sham/placebo acupuncture. Four trials compared acupuncture to oral hygiene/usual care. Only one clinical trial used oral care sessions as control group. For all the included studies, the quality for all the main outcomes has been assessed as low. Although some publications suggest a positive effect of acupuncture on either salivary flow rate or subjective dry mouth feeling, the studies are inconclusive about the potential effects of acupuncture.

CONCLUSIONS

Insufficient evidence is available to conclude whether acupuncture is an evidence-based treatment option for xerostomia/hyposalivation. Further well-designed, larger, double blinded trials are required to determine the potential benefit of acupuncture. Sample size calculations should be performed before before initiating these studies.

Validity and reliability of a Portuguese version of the Summated Xerostomia Inventory-5

OBJECTIVES

The aim of this study was to validate and determine the reliability of the Portuguese version of the Summated Xerostomia Inventory.

BACKGROUND

Many conditions such as head and neck radiation, autoimmune diseases or polypharmacy are characterised by hyposalivation which can affect oral and systemic quality of life. As such, this condition must be assessed, and the English version of the Xerostomia Inventory has been increasingly used to determine the severity of dry mouth perception.

MATERIALS AND METHODS

This was a descriptive cross-sectional study, which employed volunteers suffering from hyposalivation after local ethical committee clearance. Each patient signed an informed consent and responded to the Portuguese version of the questionnaire in the form of an interview. This was repeated again after 2 weeks. A standard single question provided a validity check. Data were analysed using Cronbach's α to test its reliability and total and interitem correlation, and intraclass correlation to determine its internal consistency and test-retest reliability. Significance was set at .05.

RESULTS

A sample of 103 volunteers was recruited. Cronbach's α was .84 and .87 for the first and second test administrations, respectively. The intraclass correlation coefficient value for the test-retest reliability was .93, and scores for the individual items ranged from .79 to .90. The correlation between the total score of the questionnaire and standard single dry mouth question was .66, indicating a very good correlation.

CONCLUSION

Demonstrating excellent psychometric properties, the Summated Xerostomia Inventory (Portuguese Version) is a valid tool for quantifying Xerostomia in a dry mouth-afflicted population.

Beneficial Effects of Adjuvant Melatonin in Minimizing Oral Mucositis Complications in Head and Neck Cancer Patients Receiving Concurrent Chemoradiation

OBJECTIVES

Oral mucositis is a major cause of pain and delayed cancer treatment leading to poor survival in head and neck cancer patients receiving concurrent chemoradiation. The study evaluated the effect of adjuvant melatonin on minimizing oral mucositis complications to reduce these treatment delays and interruptions.

DESIGN

A randomized, double-blind, double dummy, placebo-controlled clinical trial.

SETTING

Ubon Ratchathani Cancer Hospital, Thailand.

PARTICIPANTS

Thirty-nine head and neck cancer patients receiving concurrent chemoradiation (5 days/week of radiation plus chemotherapy three or six cycles).

METHODS

Patients were randomized to receive 20 mg melatonin gargle (or matched placebo) before each irradiation, and 20 mg melatonin capsules (or matched placebo) taken nightly during 7 weeks of concurrent chemoradiation. Endpoints were oral mucositis events (incidence and time to grade 3 mucositis or grade 2 xerostomia), pain medication consumption and quality of life (QOL).

RESULTS

Melatonin group reported lower incidence of grade 3 oral mucositis (42% vs. 55%) and grade 2 xerostomia (20% vs. 21%); no statistical significance was detected. Melatonin regimen delayed onset of grade 3 mucositis (median 34 days vs. 50 days; p = 0.0318), allowing median time of 16 more patient visits before its onset and fewer interrupted treatments due to oral mucositis were reported (n = 1 vs. n = 5). There was no difference of grade 2 xerostomia (median 32 days vs. 50 days; p = 0.624). Morphine consumption was also reduced (median 57 mg vs. 0 mg; p = 0.0342), while QOL was comparable during the study period.

CONCLUSION

Adjuvant melatonin delayed the onset of oral mucositis, which enables uninterrupted cancer treatment and reduced the amount of morphine used for pain treatment.

Biopolymeric Mucin and Synthetic Polymer Analogs: Their Structure, Function and Role in Biomedical Applications

Mucin networks are viscoelastic fibrillar aggregates formed through the complex self-association of biopolymeric glycoprotein chains. The networks form a lubricious, hydrated protective shield along epithelial regions within the human body. The critical role played by mucin networks in impacting the transport properties of biofunctional molecules (e.g., biogenic molecules, probes, nanoparticles), and its effect on bioavailability are well described in the literature. An alternate perspective is provided in this paper, presenting mucin’s complex network structure, and its interdependent functional characteristics in human physiology. We highlight the recent advances that were achieved through the use of mucin in diverse areas of bioengineering applications (e.g., drug delivery, biomedical devices and tissue engineering). Mucin network formation is a highly complex process, driven by wide variety of molecular interactions, and the network possess structural and chemical variations, posing a great challenge to understand mucin’s bulk behavior. Through this review, the prospective potential of polymer based analogs to serve as mucin mimic is suggested. These analog systems, apart from functioning as an artificial model, reducing the current dependency on animal models, can aid in furthering our fundamental understanding of such complex structures.

Adipose Mesenchymal Stem Cell Secretome Modulated in Hypoxia for Remodeling of Radiation-Induced Salivary Gland Damage

Background and Purpose

This study was conducted to determine whether a secretome from mesenchymal stem cells (MSC) modulated by hypoxic conditions to contain therapeutic factors contributes to salivary gland (SG) tissue remodeling and has the potential to improve irradiation (IR)-induced salivary hypofunction in a mouse model.

Materials and Methods

Human adipose mesenchymal stem cells (hAdMSC) were isolated, expanded, and exposed to hypoxic conditions (O₂ < 5%). The hypoxia-conditioned medium was then filtered to a high molecular weight fraction and prepared as a hAdMSC secretome. The hAdMSC secretome was subsequently infused into the tail vein of C3H mice immediately after local IR once a day for seven consecutive days. The control group received equal volume (500 μL) of vehicle (PBS) only. SG function and structural tissue remodeling by the hAdMSC secretome were investigated. Human parotid epithelial cells (HPEC) were obtained, expanded in vitro, and then irradiated and treated with either the hypoxia-conditioned medium or a normoxic control medium. Cell proliferation and IR-induced cell death were examined to determine the mechanism by which the hAdMSC secretome exerted its effects.

Results

The conditioned hAdMSC secretome contained high levels of GM-CSF, VEGF, IL-6, and IGF-1. Repeated systemic infusion with the hAdMSC secretome resulted in improved salivation capacity and increased levels of salivary proteins, including amylase and EGF, relative to the PBS group. The microscopic structural integrity of SG was maintained and salivary epithelial (AQP-5), endothelial (CD31), myoepithelial (α-SMA) and SG progenitor cells (c-Kit) were successfully protected from radiation damage and remodeled. The hAdMSC secretome strongly induced proliferation of HPEC and led to a significant decrease in cell death in vivo and in vitro. Moreover, the anti-apoptotic effects of the hAdMSC secretome were found to be promoted after hypoxia-preconditioning relative to normoxia-cultured hAdMSC secretome.

Conclusion

These results show that the hAdMSC secretome from hypoxic-conditioned medium may provide radioprotection and tissue remodeling via release of paracrine mediators.