Efficacy and safety of pilocarpine for radiation-induced xerostomia in patients with head and neck cancer: A systematic review and meta-analysis

Does lower dose pilocarpine have a role in radiation-induced xerostomia in the modern radiotherapy era? A single-center experience based on patient-reported outcome measures

PURPOSE

This study aims to investigate the efficacy of lower dose pilocarpine in alleviating late dry mouth symptoms in head and neck cancer patients received radiotherapy.

METHODS

Eighteen head and neck cancer patients experiencing persistent dry mouth were enrolled in this study. All participants started pilocarpine treatment a median of 6 months post-radiotherapy. Initially, patients received pilocarpine at 5 mg/day, with a gradual increase to the recommended dose of 15 mg/day. A Patient-Reported Outcome Measurement (PROMs) questionnaire assessed symptoms' severity related to hyposalivation.

RESULTS

All patients reported symptomatic dry mouth above grade 2 before starting the medication. Pilocarpine treatment continued based on patients' self-assessment, with a median duration of 12 months (range, 3-36 months). The median daily maintenance dose was 10 mg (range, 5 to 20 mg). Total PROMs scores significantly decreased following medication, from 13 points (range 7-18 points) to 7 points (range 4-13 points) (p = 0.001). Significant improvements were observed in questions related to dry mouth (p < 0.001), water intake during eating (p = 0.01), carrying water (p = 0.01), taste (p < 0.001), and water intake during speech (p < 0.001). Initial and maintenance doses of pilocarpine were lower, and the duration of pilocarpine usage was shorter in patients treated with intensity-modulated radiation therapy compared to conformal radiotherapy (12 months vs. 25 months, p = 0.04).

CONCLUSION

Pilocarpine may be considered at doses lower for late-term dry mouth. With modern radiotherapy techniques effectively preserving the parotid gland, short-term use may be recommended in these patients. Future studies may enhance the development of a more robust patient selection criteria model.

A real-life experience of long-term use of pilocarpine in irradiated head and neck cancer patients

AIMS

To assess long-term efficacy and side effects of pilocarpine on irradiated head and neck cancer (HNC) patients in both for prevention and treatment of radiation-induced xerostomia (RIX).

METHODS

Retrospective observational study was conducted. Eligibility criteria included irradiated HNC patients who received pilocarpine at least 12 weeks either for prevention (group A) or for treatment (group B) of RIX. We collected the documented Late Effect Normal Tissue Task Force-Subjective, Objective, Management, Analytics subjective/objective grades of RIX before (only group B) and the latest visit for pilocarpine prescription, dosage, side effects, duration of treatment, and the cause of discontinuation.

RESULTS

Between December 2007 and June 2022, 182 patients were enrolled including 95 patients (52%) in group A and 87 patients (48%) in group B. Group A patients reported grades 1, 2, 3, and 4 objective RIX in 0%, 7%, 93%, and 0%. Grade 1, 2, and 3 subjective RIX were 57%, 28%, and 15%. All patients in group B had grade 3 both objective/subjective RIX. The overall improvement of objective/subjective RIX was found in 40%/83%. Discontinuation was found in 51% of patients due to tolerable symptoms or deterioration of the patient's status.

CONCLUSIONS

Based on this retrospective analysis, long-term use of pilocarpine in irradiated HNC appears feasible for both prevention and treatment of RIX.

Health from Brazilian Amazon food wastes: Bioactive compounds, antioxidants, antimicrobials, and potentials against cancer and oral diseases

Brazilian Amazon contains over 30,000 plant species and foods rich in bioactive compounds such as terpenes, phenolic acids, alkaloids, and flavonoids, of potential health benefits (antioxidant, antimicrobial, antiparasitic, anticancer, gastroprotection, prebiotic effects, among others). The existence of residues from non-edible parts of plants (leaves, roots, stems, branches, barks) or fruit wastes (peel, bagasse, seeds) in the agri-food industry and its supply chain is an important challenge in food loss and waste management. In this critical review several Amazon species, focusing on extracts/essential oils from nonedible parts or wastes, were analyzed in terms of phytochemicals, biological activity, and underlying mechanisms. We hope this review emphasizes the importance of Amazon's sustainability initiatives on population health due to the potential shown against cancer, infectious diseases, and prevention of oral diseases. It is urgent to think about the conversion of amazon food wastes and co-products into high-added-value raw materials to develop novel drugs, food packaging systems, or nutraceutical foods.

Dental considerations for head and neck cancer: A clinical review

Introduction

Radiotherapy is one of the treatment modalities for the treatment of head and neck cancer (HNC). However, it leads to the development of chronic and acute side effects. These side effects impact negatively on the patient's quality of life and oral functioning. This clinical review aims to provide basic information about HNC, understand the impact of radiotherapy on oral health, and explain the role of dental care providers for HNC patients during the pre-and post-radiotherapy time.

Materials and Methods

Electronic databases (i.e., PubMed, Scopus, and Google Scholar) were searched using defined keywords. The main inclusion criteria were any studies describing "dental management of patients with head and neck cancer" and "dental management of patients treated with radiotherapy."

Results

Thematic analysis was used to summaries the findings of the included studies (n = 102) into main headings and subheadings. All studies were published between 1970 and 2023.

Conclusion

The number of HNC patients is increasing. This necessitates the need for raising the awareness of dental care providers to the side-effects of HNC therapy which includes treatment with radiotherapy, chemotherapy, and/or surgery. Dental care providers should understand the common side-effects and their treatments besides their role in the pre- (i.e., dental extraction of teeth with poor prognosis and maintaining good oral hygiene) and post- (i.e., oral rehabilitation and post-HNC dental care) radiotherapy dental care.

The Role of Dental Practitioners in the Management of Oncology Patients: The Head and Neck Radiation Oncology Patient and the Medical Oncology Patient

This narrative review addresses the role of a dentist in the management of oncology patients, highlighting the oral complications that arise in head and neck radiation oncology patients and medical oncology patients. The prevention and management of these complications are discussed.

Manejo odontológico de las manifestaciones orales inducidas por radioterapia de cabeza y cuello

La radioterapia es una de las primeras opciones de tratamiento para el cáncer de cabeza y cuello; sin embargo, puede ocasionar diversas manifestaciones secundarias en la cavidad oral tales como mucositis oral, xerostomía, infecciones orales oportunistas, osteorradionecrosis y trismo. El presente artículo tiene como objetivo describir el manejo preventivo y terapéutico de las complicaciones orales inducidas por radioterapia de cabeza y cuello en la práctica odontológica propuestos hasta la actualidad. Se encontraron diversas medidas que han logrado reducir la incidencia y gravedad de dichas manifestaciones orales; sin embargo, aún existen algunas que requieren de más estudios para confirmar su efectividad. Palabras clave: cáncer de cabeza y cuello; manifestaciones bucales; radioterapia; terapéutica.

Xerostomia and Its Cellular Targets

Xerostomia, the subjective feeling of a dry mouth associated with dysfunction of the salivary glands, is mainly caused by radiation and chemotherapy, various systemic and autoimmune diseases, and drugs. As saliva plays numerous essential roles in oral and systemic health, xerostomia significantly reduces quality of life, but its prevalence is increasing. Salivation mainly depends on parasympathetic and sympathetic nerves, and the salivary glands responsible for this secretion move fluid unidirectionally through structural features such as the polarity of acinar cells. Saliva secretion is initiated by the binding of released neurotransmitters from nerves to specific G-protein-coupled receptors (GPCRs) on acinar cells. This signal induces two intracellular calcium (Ca2+) pathways (Ca2+ release from the endoplasmic reticulum and Ca2+ influx across the plasma membrane), and this increased intracellular Ca2+ concentration ([Ca2+]i) causes the translocation of the water channel aquaporin 5 (AQP5) to the apical membrane. Consequently, the GPCR-mediated increased [Ca2+]i in acinar cells promotes saliva secretion, and this saliva moves into the oral cavity through the ducts. In this review, we seek to elucidate the potential of GPCRs, the inositol 1,4,5-trisphosphate receptor (IP3R), store-operated Ca2+ entry (SOCE), and AQP5, which are essential for salivation, as cellular targets in the etiology of xerostomia.

World Workshop on Oral Medicine VIII: Development of a Core Outcome Set for Dry Mouth: A Systematic Review of Outcome Domains for Xerostomia

OBJECTIVE

The purpose of this study was to identify all outcome domains used in clinical studies of xerostomia, that is, subjective sensation of dry mouth. This study is part of the extended project "World Workshop on Oral Medicine Outcomes Initiative for the Direction of Research" to develop a core outcome set for dry mouth.

STUDY DESIGN

A systematic review was performed on MEDLINE, EMBASE, CINAHL, and Cochrane Central Register of Controlled Trials databases. All clinical and observational studies that assessed xerostomia in human participants from 2001 to 2021 were included. Information on outcome domains was extracted and mapped to the Core Outcome Measures in Effectiveness Trials taxonomy. Corresponding outcome measures were summarized.

RESULTS

From a total of 34,922 records retrieved, 688 articles involving 122,151 persons with xerostomia were included. There were 16 unique outcome domains and 166 outcome measures extracted. None of these domains or measures were consistently used across all the studies. The severity of xerostomia and physical functioning were the 2 most frequently assessed domains.

CONCLUSION

There is considerable heterogeneity in outcome domains and measures reported in clinical studies of xerostomia. This highlights the need for harmonization of dry mouth assessment to enhance comparability across studies and facilitate the synthesis of robust evidence for managing patients with xerostomia.

Use and efficacy of mouthwashes in elderly patients: A systematic review of randomized clinical trials

INTRODUCTION

A higher prevalence of oral problems has been observed in the elderly population. One of the treatment options for some of these pathologies is the administration of mouthwashes combined with mechanical removal techniques. Besides, each type of oral rinse treats certain oral diseases, and it should be selected for each specific situation.

OBJECTIVE

To determine the use and efficacy of mouthwashes in the elderly as a treatment for various pathologies, to indicate the most common kinds of mouth-rinses used, the diseases treated with them, their efficacy in each treatment, and their effectiveness when they are combined with other treatments.

MATERIAL AND METHODS

The review has been carried out following the PRISMA 2020 Statement. Individualized bibliographic searches were performed in five databases. Randomized clinical trials are included in patients over 60 years old where mouthwashes were administered to treat or prevent specific diseases. The PICO question aimed to assess what type of mouthwashes elderly patients use, what they use them for, and their efficacy. Study selection, data extraction, and quality analysis were achieved using the RoB-2 guide.

RESULTS

Thirteen articles were chosen to perform the qualitative analysis. The bibliometric analysis was carried out. We have eleven randomized controlled clinical trials and two uncontrolled. The mouthwash more used was chlorhexidine, followed by essential oils and fluorides. The most studied pathologies were a periodontal disease, caries, candidiasis, denture stomatitis, and xerostomia. Chlorhexidine used weekly is effective as antiplaque and antigingivitis. Fluorides effectively prevent and reverse caries; nystatin and essential oils to treat candidiasis; and pilocarpine rinse to manage xerostomia.

CONCLUSIONS

The included studies show that mouthwashes are widely extended in the elderly population, and each sort is specifically designed for treating a particular condition.

Herbal Formula SS-1 Increases Tear Secretion for Sjögren's Syndrome

Background: Sjögren’s syndrome (SS) is an autoimmune inflammatory disease that primarily affects the exocrine glands, leading to glandular dysfunction. The hallmark symptoms of SS are dry eyes and mouth, compromising the quality of life of patients and decreasing their capacity to perform their daily activities.

Objective: This study aims to evaluate the efficacy of the herbal formula SS-1 for its potential therapeutic benefits for patients with Sjögren’s syndrome.

Materials and Methods: The bioactivity profile of SS-1 was determined using four different SS-1 concentrations across 12 human primary cell systems of the BioMAP profile. After that, a randomized, double-blind, crossover, placebo-controlled trial was performed including 57 patients treated with SS-1 for 28 weeks.

Results: Biologically multiplexed activity profiling in cell-based models indicated that SS-1 exerted anti-proliferative activity in B cells and promoted anti-inflammatory and immunomodulatory activity. In the clinical trial, Schirmer’s test results revealed significant improvements in both eyes, with increases of 3.42 mm (95% CI, 2.44–4.41 mm) and 3.45 mm (95% CI, 2.32–4.59 mm), respectively, and a significant reduction in artificial tear use, which was −1.38 times/day, 95% CI, −1.95 to −0.81 times/day. Moreover, the increases in B-cell activating factor (BAFF) and B-cell maturation antigen (BCMA) levels were dampened by 53.20% (295.29 versus 555.02 pg/ml) and 58.33% (99.16 versus 169.99 pg/ml), respectively.

Conclusion: SS-1 treatment significantly inhibited B-cell maturation antigen. No serious drug-related adverse effects were observed. Oral SS-1 administration may be a complementary treatment for Sjögren’s syndrome.

Xerostomia: an immunotherapy-related adverse effect in cancer patients

PURPOSE

Xerostomia is an underrecognized adverse effect of immunotherapy (IO) that can significantly impact patients' quality of life by leading to poor nutritional status, dental caries, and oral candidiasis. The purpose of this case series was to describe the onset, severity, clinical course, and management of IO-induced xerostomia.

METHODS

This was a retrospective case series conducted at an outpatient cancer center. Data collection was conducted via chart review. The severity of dry mouth symptoms was graded using the Common Terminology Criteria for Adverse Events (CTCAE) version 5.0.

RESULTS

Six patients with advanced solid tumors who received a PD-1 inhibitor or PD-1/CTLA-4 inhibitor combination therapy were evaluated. The median time to onset of xerostomia was 4.5 months overall, though symptoms developed sooner in patients who received IO as subsequent-line therapy (median = 1.9 months). All patients developed other immune-related adverse events (IRAEs) such as hypothyroidism. Five patients (83%) had grade 2 dry mouth symptoms, and similarly, 5 patients eventually required prescription medications such as sialogogues and topical or systemic corticosteroids to alleviate symptoms. Two patients (33%) required interruptions in IO. All 3 patients who received cevimeline noticed improvement in symptoms, and one patient who received prednisone dosed at 1 mg/kg/day tapered over 5 weeks also experienced significant relief.

CONCLUSION

While the optimal management of IO-induced xerostomia has not yet been established by national guidelines, increased awareness can prompt faster initiation of supportive care measures that can prevent significant discomfort and poor oral intake. Thoughtful use of over-the-counter topical agents, sialogogues, corticosteroids, and treatment interruptions can help improve tolerability of this adverse effect.

Longitudinal Multiparametric MRI Assessment of Irradiated Salivary Gland in a Rat Model: Correlated With Histological Findings

BACKGROUND

Several magnetic resonance imaging (MRI) sequences have been applied to assess injured glands but without histological validation.

PURPOSE

To evaluate longitudinal changes in multiparametric MRI (mp-MRI) of irradiated salivary glands in a rat model and investigate correlations between mp-MRI and histological findings.

STUDY TYPE

Prospective.

ANIMAL MODEL

Submandibular glands of 36 rats were radiated using a single dose of 15 Gy X-ray (irradiation [IR] group), and 6 other rats were enrolled into sham-IR group. mp-MRI were scanned 1 day after sham-IR (n = 6), or 1, 2, 4, 8, 12, 24 weeks after IR (n = 36, 6 per subgroup).

FIELD STRENGTH/SEQUENCE

A 3.0-T/Diffusion-weighted imaging (DWI), readout-segmented echo-planar imaging (EPI) sequence; intravoxel incoherent motion DWI, single-shot EPI sequence; T1 mapping, dual-flip-angle gradient-echo sequence with volumetric interpolated breath-hold examination; T2 mapping, turbo spin-echo sequence.

ASSESSMENT

Parameters including apparent diffusion coefficient (ADC), pure diffusion coefficient (D), pseudo-diffusion coefficient (D^* ), perfusion fraction (f), T1 and T2 value were obtained. Histological examinations, including hematoxylin and eosin staining (for acinar cell fraction [AC%] detection), Masson's trichrome staining (for degree of fibrosis [F%] determination) and CD34-immunohistochemical staining (for microvessel density [MVD] calculation), were performed at corresponding time points.

STATISTICAL TESTS

One-way analysis of variance was used to compare the mp-MRI and histological parameters among different groups. Spearman correlation analysis was applied to determine the correlation between mp-MRI and histological parameters. Two-sided P ≤ 0.05 was considered statistically significant.

RESULTS

Changes of mp-MRI parameters (ADC, D, D^* , f, T1, T2) and histological results (AC%, F%, MVD) among the seven groups were all significant. ADC, D, and T2 values negatively correlated with AC% (ADC, r = -0.728; D, r = -0.773; T2, r = -0.600), f positively correlated with MVD (r = 0.496), and T1 values positively correlated with F% (r = 0.714). DATA CONCLUSION: mp-MRI might be able to noninvasively and quantitatively evaluate the dynamic pathological changes within the irradiated salivary glands.

EVIDENCE LEVEL

1 TECHNICAL EFFICACY: Stage 2.

Radiation-induced swallowing dysfunction in patients with head and neck cancer: A literature review

Swallowing dysfunction is a prevailing state following radiotherapy in patients with head and neck cancer. Following the advancement of cancer treatment in recent years, the survival rate of head and neck cancer has gradually increased. Simultaneously, patients with head and neck cancer suffer due to the long-duration and more prominent swallowing dysfunction states. Based on an extensive literature review, we aimed to explore the mechanisms, risk factors, and clinical evaluations of swallowing dysfunction and their related symptoms following radiotherapy. These include functional changes of the muscles, trismus, xerostomia, neuropathy, and lymphedema. When swallowing dysfunction occurs, patients usually seek medical help and are referred for rehabilitation therapy, such as muscle strengthening and tongue resistance exercise. Furthermore, clinicians should discuss with patients how and when to place the feeding tube. Only through detailed evaluation and management can swallowing dysfunction resolve and improve the quality of life of patients with head and neck cancer following radiotherapy.

Aging-Related Metabolic Dysfunction in the Salivary Gland: A Review of the Literature

Aging-related salivary dysfunction commonly induces the poor oral health, including decreased saliva flow and dental caries. Although the clinical significance of the salivary glands is well-known, the complex metabolic pathways contributing to the aging-dysfunction process are only beginning to be uncovered. Here, we provide a comprehensive overview of the metabolic changes in aging-mediated salivary gland dysfunction as a key aspect of oral physiology. Several metabolic neuropeptides or hormones are involved in causing or contributing to salivary gland dysfunction, including hyposalivation and age-related diseases. Thus, aging-related metabolism holds promise for early diagnosis, increased choice of therapy and the identification of new metabolic pathways that could potentially be targeted in salivary gland dysfunction.

Synthesis, Biological, and Computational Evaluation of Antagonistic, Chiral Hydrobenzoin Esters of Arecaidine Targeting mAChR M1

Muscarinic acetylcholine receptors (mAChRs) are a pivotal constituent of the central and peripheral nervous system. Yet, therapeutic and diagnostic applications thereof are hampered by the lack of subtype selective ligands. Within this work, we synthesized and chemically characterized three different stereoisomers of hydrobenzoin esters of arecaidine by NMR, HR-MS, chiral chromatography, and HPLC-logP. All compounds are structurally eligible for carbon-11 labeling and show appropriate stability in Dulbecco’s phosphate-buffered saline (DPBS) and F12 cell culture medium. A competitive radioligand binding assay on Chinese hamster ovary cell membranes comprising the human mAChR subtypes M1-M5 showed the highest orthosteric binding affinity for subtype M1 and a strong influence of stereochemistry on binding affinity, which corresponds to in silico molecular docking experiments. K_i values toward M1 were determined as 99 ± 19 nM, 800 ± 200 nM, and 380 ± 90 nM for the (R,R)-, (S,S)-, and racemic (R,S)-stereoisomer, respectively, highlighting the importance of stereochemical variations in mAChR ligand development. All three stereoisomers were shown to act as antagonists toward mAChR M1 using a Fluo-4 calcium efflux assay. With respect to future positron emission tomography (PET) tracer development, the (R,R)-isomer appears especially promising as a lead structure due to its highest subtype selectivity and lowest K_i value.

Topical pilocarpine for xerostomia in patients with head and neck cancer treated with radiotherapy

OBJECTIVE

To evaluate a pilocarpine spray as a treatment for xerostomia in patients treated with radiotherapy (RT) for head and neck cancer (HNC).

METHODS

This was a placebo-controlled, double-blind, crossover clinical trial of patients complaining of dry mouth after RT for HNC. Forty patients were randomly assigned to either placebo or pilocarpine (1.54%) spray and instructed to use three times a day for 3 months. After 1-month washout period, patients were crossed over to receive placebo or pilocarpine. The assessments were salivary flow (Stimulated Whole Saliva Flow - SWSF), xerostomia (Xerostomia Inventory - XI), and quality of life (QoL/Oral Health Impact Profile - OHIP-14), assessed at baseline, 1 hr (only SWSF), and at 1, 2, and 3 months of treatment.

RESULTS

Posttreatment SWFS was not statistically different between pilocarpine and placebo regardless of the treatment sequence (paired T test; p > .05), except for the SWFS rates at 2 months after therapy. When comparing pilocarpine with placebo in the time points, there was no significant difference (p > .05) for QoL or XI. Significant differences in improvement in QoL and xerostomia experience appeared along time for pilocarpine group.

CONCLUSION

The topical application of pilocarpine spray tested was similar to placebo on SWSF assessments in patients treated with RT for HNC.

Salivary Gland Hypofunction and Xerostomia in Head and Neck Radiation Patients

BACKGROUND

The most manifest long-term consequences of radiation therapy in the head and neck cancer patient are salivary gland hypofunction and a sensation of oral dryness (xerostomia).

METHODS

This critical review addresses the consequences of radiation injury to salivary gland tissue, the clinical management of salivary gland hypofunction and xerostomia, and current and potential strategies to prevent or reduce radiation injury to salivary gland tissue or restore the function of radiation-injured salivary gland tissue.

RESULTS

Salivary gland hypofunction and xerostomia have severe implications for oral functioning, maintenance of oral and general health, and quality of life. Significant progress has been made to spare salivary gland function chiefly due to advances in radiation techniques. Other strategies have also been developed, e.g., radioprotectors, identification and preservation/expansion of salivary stem cells by stimulation with cholinergic muscarinic agonists, and application of new lubricating or stimulatory agents, surgical transfer of submandibular glands, and acupuncture.

CONCLUSION

Many advances to manage salivary gland hypofunction and xerostomia induced by radiation therapy still only offer partial protection since they are often of short duration, lack the protective effects of saliva, or potentially have significant adverse effects. Intensity-modulated radiation therapy (IMRT), and its next step, proton therapy, have the greatest potential as a management strategy for permanently preserving salivary gland function in head and neck cancer patients.Presently, gene transfer to supplement fluid formation and stem cell transfer to increase the regenerative potential in radiation-damaged salivary glands are promising approaches for regaining function and/or regeneration of radiation-damaged salivary gland tissue.

Late side effects of radiation treatment for head and neck cancer

Patients undergoing radiation therapy for head and neck cancer (HNC) experience significant early and long-term side effects. The likelihood and severity of complications depends on a number of factors, including the total dose of radiation delivered, over what time it was delivered and what parts of the head and neck received radiation. Late side effects include: permanent loss of saliva; osteoradionecrosis; radiation recall myositis, pharyngoesophageal stenosis; dental caries; oral cavity necrosis; fibrosis; impaired wound healing; skin changes and skin cancer; lymphedema; hypothyroidism, hyperparathyroidism, lightheadedness, dizziness and headaches; secondary cancer; and eye, ear, neurological and neck structures damage. Patients who undergo radiotherapy for nasopharyngeal carcinoma tend to suffer from chronic sinusitis. These side effects present difficult challenges to the patients and their caregivers and require life-long strategies to alleviate their deleterious effect on basic life functions and on the quality of life. This review presents these side effects and their management.

Mouth-Watering Results: Clinical Need, Current Approaches, and Future Directions for Salivary Gland Regeneration

Permanent damage to the salivary glands and resulting hyposalivation and xerostomia have a substantial impact on patient health, quality of life, and healthcare costs. Currently, patients rely on lifelong treatments that alleviate the symptoms, but no long-term restorative solutions exist. Recent advances in adult stem cell enrichment and transplantation, bioengineering, and gene transfer have proved successful in rescuing salivary gland function in a number of animal models that reflect human diseases and that result in hyposalivation and xerostomia. By overcoming the limitations of stem cell transplants and better understanding the mechanisms of cellular plasticity in the adult salivary gland, such studies provide encouraging evidence that a regenerative strategy for patients will be available in the near future.

Pilocarpine induces the residual secretion of salivary fluid in perfused submandibular glands of rats

Pilocarpine is an M3 muscarinic agonist that is widely used for the treatment of xerostomia caused by various diseases and medical conditions. Pilocarpine induced the secretion of salivary fluid in perfused submandibular glands of rats. The secretion of salivary fluid observed after removal of pilocarpine was referred to as residual fluid secretion. The volume of fluid and time of the residual secretion depended on the dose of pilocarpine. Such a residual effect of pilocarpine was observed on fluid secretion via the paracellular pathway and oxygen consumption. When a muscarinic antagonist was added to the perfusate immediately after cessation of pilocarpine, residual secretion of salivary fluid did not occur. These observations indicate that the residual secretion of salivary fluid is a characteristics of the interaction of pilocarpine with muscarinic receptors.

A suspected case of drug-induced tubulointerstitial nephritis by pilocarpine hydrochloride

A 63-year-old man with pharyngeal cancer had been prescribed pilocarpine hydrochloride for xerostomia after concomitant chemoradiotherapy. After 6 months of taking pilocarpine hydrochloride, he was referred to our hospital due to gradually developing renal insufficiency. The patient underwent detailed urinalysis, blood chemistry analysis, immune-serology testing. A renal biopsy was also performed. He was diagnosed with chronic tubulointerstitial nephritis (TIN) caused by lymphocytic infiltration of the interstitium, tubular atrophy, and interstitial fibrotic changes. Infections, autoimmune diseases, and genetic factors were ruled out as causes of TIN; a drug-induced lymphocyte stimulation test confirmed that he had high stimulation index scores for pilocarpine hydrochloride and a normal range stimulation score for other supplements. These results indicated that the TIN could have been induced by pilocarpine hydrochloride. Drug discontinuation partly improved his renal function and tubule marker levels. To our knowledge, this is the first report of TIN following administration of pilocarpine hydrochloride. This finding could contribute to future treatment decisions for patients with TIN and those using pilocarpine hydrochloride.

Pilocarpine and artificial saliva for the treatment of xerostomia and xerophthalmia in Sjögren syndrome: a double-blind randomized controlled trial

BACKGROUND

Sjögren syndrome (SS) is associated with xerostomia and xerophthalmia. Pilocarpine has been shown to stimulate the secretion of saliva.

OBJECTIVES

To investigate and compare the efficacy of pilocarpine and artificial saliva as symptomatic treatments for xerostomia and xerophthalmia in patients with SS.

METHODS

A double-blind randomized controlled study was performed. A total of 72 patients with SS were assigned randomly to receive 10 drops of pilocarpine (5 mg) or 10 drops of artificial saliva orally, three times daily for 12 weeks. Whole saliva and tear flow were evaluated at baseline and periodically throughout the study to provide a global assessment of dryness and to report any adverse effects.

RESULTS

Patients receiving pilocarpine had a statistically significant improvement in their salivary flow (P < 0·001), lacrimal flow (P < 0·001) and their subjective global assessment (P < 0·001), compared with patients who received artificial saliva. The most common side-effects were sialorrhoea and nausea.

CONCLUSIONS

Pilocarpine is more effective than artificial saliva for enhancing salivary and lacrimal secretion in patients with SS. This is the first study to compare the efficacy of pilocarpine and artificial saliva for the treatment of xerostomia and xerophthalmia in SS.

Management of Radiation Toxicity in Head and Neck Cancers

Head and neck cancers account for approximately 3% of all cancers in the United States with 62,000 new cases diagnosed annually. The global incidence is approximately 700,000 new cases a year. There has also been a recent increase in human papilloma virus-related oropharyngeal cancers. External beam radiation therapy (RT) is commonly used as an effective therapy for head and neck (H&N) cancers. This is used as a definitive treatment (alone or in combination with chemotherapy) or as an adjuvant treatment after surgical resection of the tumors. Because of the complex anatomy of the H&N region, several critical structures in and around the area receive radiation treatment. This includes the neural structures (brainstem, spinal cord, and brachial plexus), salivary glands, mucosa, major blood vessels, and swallowing musculature. Careful RT planning is necessary to avoid or mitigate the side effects of treatment. This review discusses some of the major acute and late side effects of RT for H&N cancers and provides evidence-based guidelines for their management. Patient-reported outcomes and quality-of-life implications are also discussed.

Treatment of late sequelae after radiotherapy for head and neck cancer

Radiotherapy (RT) is used to treat approximately 80% of patients with cancer of the head and neck. Despite enormous advances in RT planning and delivery, a significant number of patients will experience radiation-associated toxicities, especially those treated with concurrent systemic agents. Many effective management options are available for acute RT-associated toxicities, but treatment options are much more limited and of variable benefit among patients who develop late sequelae after RT. The adverse impact of developing late tissue damage in irradiated patients may range from bothersome symptoms that negatively affect their quality of life to severe life-threatening complications. In the region of the head and neck, among the most problematic late effects are impaired function of the salivary glands and swallowing apparatus. Other tissues and structures in the region may be at risk, depending mainly on the location of the irradiated tumor relative to the mandible and hearing apparatus. Here, we review the available evidence on the use of different therapeutic strategies to alleviate common late sequelae of RT in head and neck cancer patients, with a focus on the critical assessment of the treatment options for xerostomia, dysphagia, mandibular osteoradionecrosis, trismus, and hearing loss.

Current Status of Targeted Radioprotection and Radiation Injury Mitigation and Treatment Agents: A Critical Review of the Literature

As more cancer patients survive their disease, concerns about radiation therapy-induced side effects have increased. The concept of radioprotection and radiation injury mitigation and treatment offers the possibility to enhance the therapeutic ratio of radiation therapy by limiting radiation therapy-induced normal tissue injury without compromising its antitumor effect. Advances in the understanding of the underlying mechanisms of radiation toxicity have stimulated radiation oncologists to target these pathways across different organ systems. These generalized radiation injury mechanisms include production of free radicals such as superoxides, activation of inflammatory pathways, and vascular endothelial dysfunction leading to tissue hypoxia. There is a significant body of literature evaluating the effectiveness of various treatments in preventing, mitigating, or treating radiation-induced normal tissue injury. Whereas some reviews have focused on a specific disease site or agent, this critical review focuses on a mechanistic classification of activity and assesses multiple agents across different disease sites. The classification of agents used herein further offers a useful framework to organize the multitude of treatments that have been studied. Many commonly available treatments have demonstrated benefit in prevention, mitigation, and/or treatment of radiation toxicity and warrant further investigation. These drug-based approaches to radioprotection and radiation injury mitigation and treatment represent an important method of making radiation therapy safer.

Efficacy of Traditional Chinese Medicine in Xerostomia and Quality of Life during Radiotherapy for Head and Neck Cancer: A Prospective Pilot Study

Xerostomia is one of the most common acute and late complications of radiotherapy for head and neck cancer, and it affects quality of life. We conducted a prospective study to evaluate the efficacy of traditional Chinese medicine (TCM) in toxicities and quality of life during radiotherapy. Head and neck cancer patients who were scheduled for radiotherapy were checked for inclusion/exclusion criteria before enrollment. Patients in the study group (inpatients) were hospitalized in a Chinese medicine ward and received concomitant TCM intervention during radiotherapy, while those in the control group (outpatients) received only conventional cancer treatments at the Western outpatient department. The primary end point was amelioration of postradiotherapy side effects. The secondary end points were quality of life during the cancer therapy and occurrence of adverse events following the TCM treatments. Thirty inpatients and 50 outpatients completed the study. Compared to the control group, those in the TCM group had decreased severity of xerostomia. There was no treatment-related impairment of renal or hepatic function among TCM group. Although better outcomes of social contact, dyspnea, physical and emotional function, and financial problems were found in the TCM group, we need further confirmation about the impact of hospitalization itself on these results.