Nutritional interventions for the prevention and treatment of cancer therapy-induced oral mucositis: an umbrella review of systematic reviews and meta-analysis

CONTEXT

To date, the efficacy of nutritional interventions on oral mucositis (OM) in patients with cancer, and the quality of this evidence have not been explored.

OBJECTIVE

The goal of this umbrella review was to provide a comprehensive evaluation of nutritional interventions for patients with cancer with OM, as well as to assess the quality of this evidence.

DATA SOURCES

Meta-analyses were searched for using PubMed, Scopus, and ISI Web of Science databases until December 2021, with no time restrictions.

DATA EXTRACTION

Meta-analyses of randomized control trials that evaluated the effects of nutritional interventions on the incidence of OM in patients with cancer had inclusion criteria for this umbrella review. Data extraction, quality assessment of meta-analyses, and primary studies were done independently by 2 authors. The Grading of Recommendations Assessment, Development, and Evaluation technique was used to grade the certainty of evidence.

DATA ANALYSIS

A total of 26 meta-analyses were included in this umbrella review. The results showed that honey, glutamine, and propolis can reduce the incidence of severe OM, based on moderate evidence quality. In addition, zinc supplementation significantly reduced the incidence of OM, regardless of symptom severity; however, low certainty of the evidence was observed. The effects of vitamin E, curcumin, and probiotics on OM were not statistically significant.

CONCLUSION

This umbrella review shows that honey, glutamine, and propolis can significantly reduce the incidence of severe OM. These findings need to be confirmed with well-designed, longitudinal randomized controlled trials.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42022301010.

Interventions for the Prevention of Oral Mucositis in Patients Receiving Cancer Treatment: Evidence from Randomised Controlled Trials

Oral mucositis is a common and most debilitating complication associated with cancer therapy. Despite the significant clinical and economic impact of this condition, there is little to offer to patients with oral mucositis, and the medications used in its management are generally only palliative. Given that mucositis is ultimately a predictable and, therefore, potentially preventable condition, in this study we appraised the scientific literature to evaluate effective methods of prevention that have been tested in randomised controlled trials (RCTs). Published high-level evidence shows that multiple preventative methods are potentially effective in the prevention of oral mucositis induced by radiotherapy, chemotherapy, or both. Anti-inflammatory medications (including benzydamine), growth factors and cytokines (including palifermin), cryotherapy, laser-and-light therapy, herbal medicines and supplements, and mucoprotective agents (including oral pilocarpine) showed some degree of efficacy in preventing/reducing the severity of mucositis with most anticancer treatments. Allopurinol was potentially effective in the prevention of radiotherapy-induced oral mucositis; antimicrobial mouthwash and erythropoietin mouthwash were associated with a lower risk of development of severe oral mucositis induced by chemotherapy. The results of our review may assist in highlighting the efficacy and testing the effectiveness of low-cost, safe preventative measures for oral mucositis in cancer patients.

Oxidative Stress and Chemoradiation-Induced Oral Mucositis: A Scoping Review of In Vitro, In Vivo and Clinical Studies

Chemoradiation-induced mucositis is a debilitating condition of the gastrointestinal tract eventuating from antineoplastic treatment. It is believed to occur primarily due to oxidative stress mechanisms, which generate Reactive Oxygen Species (ROS). The aim of this scoping review was to assess the role of oxidative stress in the development of Oral Mucositis (OM). Studies from the literature, published in MEDLINE and SCOPUS, that evaluated the oxidative stress pathways or antioxidant interventions for OM, were retrieved to elucidate the current understanding of their relationship. Studies failing inclusion criteria were excluded, and those suitable underwent data extraction, using a predefined data extraction table. Eighty-nine articles fulfilled criteria, and these were sub-stratified into models of study (in vitro, in vivo, or clinical) for evaluation. Thirty-five clinical studies evaluated antioxidant interventions on OM's severity, duration, and pain, amongst other attributes. A number of clinical studies sought to elucidate the protective or therapeutic effects of compounds that had been pre-determined to have antioxidant properties, without directly assessing oxidative stress parameters (these were deemed "indirect evidence"). Forty-seven in vivo studies assessed the capacity of various compounds to prevent OM. Findings were mostly consistent, reporting reduced OM severity associated with a reduction in ROS, malondialdehyde (MDA), myeloperoxidase (MPO), but higher glutathione (GSH) and superoxide dismutase (SOD) activity or expression. Twenty-one in vitro studies assessed potential OM therapeutic interventions. The majority demonstrated successful a reduction in ROS, and in select studies, secondary molecules were assessed to identify the mechanism. In summary, this review highlighted numerous oxidative stress pathways involved in OM pathogenesis, which may inform the development of novel therapeutic targets.

Zinc as a complementary treatment for cancer patients: a systematic review

Zinc is a trace element that plays an important role in the immune system and cell growth. The role of zinc in cancer treatment has been discussed for some time, however without reaching an evidenced-based consensus. Therefore, we aim to critically examine and review existing evidence on the role of zinc during cancer treatment. In January 2019, a systematic search was conducted searching five electronic databases (Embase, Cochrane, PsychINFO, CINAHL and PubMed) to find studies concerning the use, effectiveness and potential harm of zinc therapy on cancer patients. Out of initial 5244 search results, 19 publications concerning 23 studies with 1230 patients were included in this systematic review. The patients treated with zinc were mainly diagnosed with head and neck cancer and underwent chemo-, radio- or concurrent radio-chemotherapy. Interventions included the intake of different amounts of zinc supplements and oral zinc rinses. Outcomes (primary endpoints) investigated were mucositis, xerostomia, dysgeusia, pain, weight, dermatitis and oral intake of nutrients. Secondary endpoints were survival data, quality of life assessments and aspects of fatigue, immune responses and toxicities of zinc. The studies were of moderate quality reporting heterogeneous results. Studies have shown a positive impact on the mucositis after radiotherapy. No protection was seen against mucositis after chemotherapy. There was a trend to reduced loss of taste, less dry mouth and oral pain after zinc substitution. No impact was seen on weight, QoL measurements, fatigue, and survival. The risk of side effects from zinc appears to be relatively small. Zinc could be useful in the prevention of oral toxicities during irradiation. It does not help in chemotherapy-induced side effects.

Efficacy of Improvised Topical Zinc (1%) Ora-Base on Oral Mucositis during Cancer Chemo-Radiation-A Randomized Study

Oral mucositis refers to erythematous and ulcerative lesions of oral mucosa during chemo/radiotherapy. Treatment modalities were directed towards reduction in severity of oral mucositis. Zinc plays an important role to retard oxidative processes and is considered as the critical component in wound healing. To compare the efficacy of zinc alone with improvised zinc preparation in reducing the severity of oral mucositis. Improvised zinc was a combination of zinc oxide, amla, tulsi and curcumin at 1% therapeutic concentrations. Seventy-five subjects undergoing chemo/radiotherapy were randomly divided into three groups: Group A (25 subjects) had received topical 5% zinc oxide paste trice daily application after food for entire treatment period, initiated 2 d prior to radiotherapy. Group B (25) received improvised zinc preparations (1%) and instructed to apply same as group A. Group C (25) received standard treatment offered by cancer hospital. All the groups were assessed for oral mucositis using WHO grading system at 7th, 14th, 21st, 28th, 35th day by the oncologist and results were tabulated for statistical analysis. Severity of oral mucositis reduced in zinc and improvised zinc group (p=0.096) when compared with controls with significant p value (0.037). Comparison of improvised zinc preparation (1%) group with only zinc group revealed that severity of overall mucositis though was not significant, was less in improvised zinc group with p value (0.029, 0.013) at 28 and 35 d respectively. Improvised zinc administration during radiation therapy was beneficial in reduction of oral mucositis during cancer treatment.

Zinc Adequacy Is Essential for the Maintenance of Optimal Oral Health

Zinc, a metal found in the Earth's crust, is indispensable for human health. In the human body, around 60% of zinc is present in muscles, 30% in bones, and the remaining 10% in skin, hair, pancreas, kidneys and plasma. An adequate zinc balance is essential for the maintenance of skeletal growth, development and function. It is also necessary for basic cellular functions including enzyme activation, cell signaling and energy metabolism. Inadequate zinc status is associated with a wide variety of systemic disorders including cardiovascular impairment, musculoskeletal dysfunctions and oromaxillary diseases. In this article, we briefly discuss the role of zinc deficiency in the genesis of various oromaxillary diseases, and explain why adequate zinc homeostasis is vital for the maintenance of oral and general health.

A Meta-Analysis on the Efficacy of Zinc in Oral Mucositis during Cancer Chemo and/or Radiotherapy-An Evidence-Based Approach

Zinc in various therapeutic doses was used on patients suffering from oral mucositis during cancer treatment. A meta-analysis was conducted to probe the role of oral zinc as a possible treatment option for oral mucositis. A literature search was done using PubMed, EBSCO, Cochrane, MedLine, ScienceDirect, ResearchGate and Google Scholar with key words. The analysis was directed to recognize and identify the use of zinc supplementations at a confidence interval (CI) 95% with p value significance taken as <0.05. A total number of 21,428 articles was retrieved. After thorough screening and assessment of the eligibility criteria, 10 articles were included in qualitative and quantitative analysis in the study. The 10 articles constituted a total sample size of 299 in the case group and 294 in the control group. Oral zinc doses used were 25 mg, 30 mg, 50 mg and 220 mg capsules and mouthwash of 0.2% zinc, as well as 0.5 g of granules dissolved in 5% sodium alginate solution. Two studies showed no significance, with the overall effect 1.61. Eight studies favored zinc over a placebo with an overall effect size of -0.89 at 95% CI of -1.08 and -0.70 which was statistically significant (Z=9.27, p<0.00001). This analysis suggests that zinc usage has shown significant reduction in the severity of oral mucositis but not prevention. The onset of the reaction was delayed and hastened healing. Pharyngeal mucositis, pain and quality of life of the individuals received no effect from zinc therapy.

Oral Zinc Sulfate for Prevention and Treatment of Chemotherapy-Induced Oral Mucositis: A Meta-Analysis of Five Randomized Controlled Trials

Chemotherapy-induced oral mucositis is an extremely serious complication faced by cancer patients. The role of oral zinc sulfate in preventing and treating chemotherapy-induced oral mucositis remains a subject of debate. The aim of this systematic review is to assess the potential of oral zinc sulfate to alleviate this morbid condition. A systematic search was conducted electronically in PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials (CENTRAL) to capture all potential randomized controlled trials investigating efficacy and safety of oral zinc sulfate in prevention and treatment of chemotherapy-induced oral mucositis, and the retrieval time was limited from their inception to April 2018. We assigned two independent investigators to perform a search, screen citations, extract information, and evaluate the risk of bias in all included trials. Subsequently, the RevMan 5.3 software was utilized to perform all statistical analyses. We included five eligible studies involving 352 patients. Meta-analysis based on limited data revealed that oral zinc sulfate failed to decrease the incidence of chemotherapy-induced oral mucositis (RR [relative risk] = 0.52, 95% CI [confidence interval] = 0.17–1.64) as well as relieve chemotherapy-induced oral mucositits grade (RR = 0.62, 95% CI = 0.11–3.56; RR = 0.70, 95% CI = 0.29–1.71). Moreover, qualitative analyses also suggested that oral zinc sulfate was not associated with reduced oral pain intensity, delayed onset of chemotherapy-induced oral mucositis, decreased adverse events, or improved quality of life compared with control regimes. Oral zinc sulfate may not provide clinical benefits in preventing or reducing incidence, severity, or pain intensity of chemotherapy-induced oral mucositis in cancer patients. However, more studies with large-scale and rigorous methods are warranted for the purpose of further investigating efficacy and safety of oral zinc sulfate for this pathologic condition due to the presence of limitations.

Efficacy and safety of oral zinc sulfate in the prevention of chemotherapy-induced oral mucositis: Protocol for a meta-analysis of randomized controlled trials

BACKGROUND

Oral mucositis has been an extremely serious complication resulted from cytotoxic effects of the chemotherapy among cancer patients. Several randomized controlled trials investigated the efficacy of zinc sulfate in prevention of this morbid condition among cancer patients undergoing chemotherapy, however conclusive findings has not yet been generated. This systematic review will assess the efficacy and safety of oral zinc sulfate for chemotherapy-induced oral mucositis.

METHODS

We will electronically search all potential citations in PubMed, EMBASE, and Cochrane Central Register of Controlled Trials (CENTRAL) from their inception to April 2018. The randomized controlled trials, which investigated the efficacy of oral zinc sulfate for chemotherapy-induced oral mucositis will be considered. We will assign 2 independent investigators to perform search, screen citations, extract data, and appraise risk of bias. And then, the primary investigator will adopt RevMan 5.3 software to complete all statistical analyses.

ETHICS AND DISSEMINATION

The findings from this systematic review and meta-analysis will be submitted to a peer-reviewed journal for publication. Moreover, we will disseminate all results in any topic-related conference.

REGISTRATION NUMBER

This protocol has been registered with a number of CRD42018093605.