Cryotherapy for oral mucositis in cancer: review of systematic reviews and meta-analysis

BACKGROUND

One of the most common side effects of cancer treatment is oral mucositis. Although studies have shown that oral cryotherapy has a favourable effect on oral mucositis, the reliability of the results is questionable.

OBJECTIVE

The goal of this umbrella review was to provide insight into the effects of oral cryotherapy against oral mucositis in patients with cancer, as well as to assess the certainty of this evidence.

METHOD

Studies were searched for through PubMed, Scopus and Web of Science, with no restrictions until August 2021. The risk ratio (RR) and 95% CI for each meta-analysis were recalculated using a random-effects model, and the certainty of the evidence was judged using Grading of Recommendations Assessment, Development and Evaluation.

RESULTS

Ten meta-analyses including 25 original RCTs that fit our inclusion criteria were included. The use of oral cryotherapy markedly reduced the occurrence of overall (RR 0.72, 95% CI 0.64 to 0.83, n=20 trials), moderate to severe (RR 0.60, 95% CI 0.45 to 0.80, n=16 trials) and severe oral mucositis (RR 0.48, 95% CI 0.34 to 0.67, n=16 trials), as well as average severity score of oral mucositis (standardised mean difference=-0.94, 95% CI -1.28 to -0.59, n=4 trials) in comparison to a control group; however, the certainty of evidence for all outcomes was rated very low.

CONCLUSION

In patients with cancer, oral cryotherapy appears to greatly lower the severity and occurrence of oral mucositis, but, with very low certainty of evidence.

Cross-sectional observational study: Investigation of zinc concentration in white patients with cancer

OBJECTIVES

Numerous studies describe the role of zinc in the immune system and metabolism. Zinc may influence the pathogenesis and prognosis of cancer. The aim of this study to determine the prevalence of zinc deficiency in patients with cancer. The study's primary objective was to evaluate the frequency of zinc deficiency in White patients with cancer and characterize the clinical factors predisposing individuals to decreased zinc concentration. The study also aimed to estimate the dose of zinc supplementation that would prevent deficiency.

METHODS

Retrospective data for this cross-sectional study were analyzed from 300 consecutive white patients diagnosed with neoplastic disease and admitted to a major oncology hospital for treatment. Zinc plasma concentration, nutritional status, body composition, and medical history of ailments and dysphagia were recorded. Supplementation was introduced in patients with zinc deficiency according to the local protocol. Zinc plasma levels were collected at follow-up visits.

RESULTS

Zinc deficiency was diagnosed in 68% of the patients. Poor nutritional status was significantly associated with zinc deficiency (low body mass index, weight loss, low albumin level). Low lean body mass (P = 0.003) and adipose tissue (P = 0.045) correlated with zinc deficiency. Patients with zinc deficiency reported dysphagia more frequently than those with normal zinc levels (18 versus 8%; P = 0.03). Squamous cell carcinoma was significantly associated with zinc deficiency (P = 0.043). Oral zinc supplementation resulted in reaching laboratory norms for plasma concentration in only 27% of patients with zinc deficiency and was not dependent on lower (10-15 mg) or higher (25-30 mg) dosing (P > 0.05).

CONCLUSIONS

Zinc deficiency is common in cachectic, malnourished patients with cancer. Nutritional guidelines for these patients should include screening for micronutrient deficiencies. Further studies are needed to determine the role, dosage, duration, and form of nutritional supplementation recommended for specific cancer diagnoses.

Efficacy of bioadhesives in the management of oral mucositis in patients undergoing radio-chemotherapy for treatment of head and neck cancer-a systematic review and meta-analysis

BACKGROUND

Management of head and neck cancers requires a multidisciplinary approach where surgery followed by radio and chemotherapy is the mainstay of treatment. The above-mentioned treatment can cause mucositis, a severely debilitating side effect. This can have a significant impact on quality of life. A recent advancing mode of drug delivery is the bioadhesive system. This interacts with mucosa by adhering to it and thereby improving the efficacy of the therapeutic agent delivered.

AIM AND OBJECTIVE

The purpose of this systematic review is to evaluate the effectiveness of bioadhesives in reducing oral mucositis and relieving pain associated with mucositis in head and neck cancer patients receiving radio-chemotherapy.

MATERIALS AND METHOD

Studies assessing the effectiveness of bioadhesives for the treatment of radiation-induced oral mucositis were retrieved from specialized databases (PubMed/MEDLINE, Scopus, ProQuest, Google Scholar, LILACS, OpenGrey) as well as institutional repositories. Data on incidence, pain reduction, resolution, and improvement of oral mucositis using bioadhesive were compiled. A Cochrane tool was used for randomized controlled trials and a JBI tool for non-randomized controlled trials and observational studies to assess the quality of included studies. Based on the eligible study data, a meta-analysis was conducted with STATA version 16, 2019 software, and 95% confidence intervals and p values greater than 0.05.

RESULTS

A total of 15 studies were included which assessed the effectiveness of bioadhesives in managing mucositis and its associated pain. Studies included in the review described either reduction, resolution, or incidence of oral mucositis respectively. A total of three meta-analyses were conducted to assess the incidence of oral mucositis and the pain associated with it, as well as the reduction in incidence. Bioadhesives showed statistically significant differences in the incidence of severe mucositis (p = 0.04). A meta-analysis comparing bioadhesives efficacy in reducing mucositis and pain associated with it found no statistically significant differences (p = 0.36).

CONCLUSION

Bioadhesives are emerging as a novel drug delivery method for treating radio-chemotherapy-induced oral mucositis because of their rapid absorption and easy application. Regardless of its benefits, clinical trials comparing it with conventional treatment methods are necessary to assess its efficacy in treating oral mucositis.

Developing Ice Cream for Mucositis Management and Improving the Nutritional Support for Pediatric Cancer Patients

  Introduction: Mucositis is one of the main complications of cancer treatment, associated with several nutritional limitations and the ability to cause secondary infections. Cryotherapy is a low-cost treatment consistent with clinical practice guidelines for treating patients with mucositis. Objective: To develop and evaluate the acceptance of ice cream for the prevention and treatment of mucositis and nutritional support of pediatric cancer patients. Method: Based on knowledge about the side effects of chemotherapy (especially in oral and gastrointestinal mucositis) and the nutritional needs of pediatric cancer patients, a literature search for ingredients that could meet the study’s objectives was undertaken. Food Technology Laboratory of the São Paulo State University (Unesp), Botucatu campus, and in partnership with Sorvetes Naturais ice cream shop in the municipality of Botucatu-SP, produced the ice cream. An acceptance test was applied in ten patients undergoing cancer treatment and 30 individuals in the control group using the 5-point mixed facial hedonic scale. Results: The final formula consisted of semi-skimmed lactose-free milk, extra virgin coconut oil, oat flour, honey, chamomile, Fortini® food supplement, demerara sugar, and stabilizer/emulsifier. 90% of patients undergoing cancer treatment rated the final product as “liked” or “loved it,” compared to 63% of the control group. Conclusion: Development of an ice cream that met the objectives of the study was possible through the choice of its composition. Honey and chamomile can favor the prevention of mucositis, and other ingredients offer the caloric density and protein supply.

Supplementation with Oral Vitamin C Prior to and during Myeloablative Chemotherapy and Autologous Haematopoietic Stem Cell Transplantation: A Pilot Study

Chemotherapy-related side effects are common in patients undergoing myeloablative chemotherapy and haematopoietic stem cell transplantation. Some, such as oral mucositis, are believed to be due to enhanced oxidative stress and inflammation. Vitamin C, a potent antioxidant with anti-inflammatory properties, becomes severely depleted following myeloablative chemotherapy. The aim of our study was to assess the feasibility and efficacy of oral vitamin C supplementation to restore and maintain adequate vitamin C concentrations in patients undergoing myeloablative chemotherapy and stem cell transplantation. We carried out a pilot randomized controlled trial in 20 patients with myeloma and lymphoma. Placebo or vitamin C tablets (1 g twice daily) were initiated one week prior to transplantation and continued for 4 weeks post-transplantation. Blood samples were collected weekly for analysis of plasma vitamin C concentrations using high-performance liquid chromatography. The patients’ symptoms and quality of life parameters were monitored using the World Health Organization oral toxicity scale and the European Organization for the Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ). Pre-supplementation with oral vitamin C doubled vitamin C concentrations relative to placebo by day 0 (median 61 vs. 31 µmol/L), with 60% of those in the vitamin C group achieving concentrations ≥ 50 µmol/L, compared with only 10% in the placebo group. Following chemotherapy and transplantation, significance between the vitamin C and placebo groups was lost by day 7, with only 30% of the patients in the vitamin C group having plasma concentrations ≥ 50 µmol/L. This was partly due to intolerance of the oral intervention due to nausea/vomiting and diarrhoea (40% of the participants in each group). Oral mucositis was also observed in 40% of the participants at day 7 or 14. Overall, our study showed that whilst short-term oral vitamin C pre-supplementation was able to restore adequate vitamin C status by day 0, ongoing supplementation could not maintain adequate vitamin C concentrations following chemotherapy and transplantation. Thus, intravenous vitamin C should be trialled as this bypasses the gastrointestinal system, negating intolerance issues and improving bioavailability of the vitamin.

Role of the microbiome in oral cancer occurrence, progression and therapy

The oral cavity, like other digestive or mucosal sites, contains a site-specific microbiome that plays a significant role in maintaining health and homeostasis. Strictly speaking, the gastrointestinal tract starts from the oral cavity, with special attention paid to the specific flora of the oral cavity. In healthy people, the microbiome of the oral microenvironment is governed by beneficial bacteria, that benefit the host by symbiosis. When a microecological imbalance occurs, changes in immune and metabolic signals affect the characteristics of cancer, as well as chronic inflammation, disruption of the epithelial barrier, changes in cell proliferation and cell apoptosis, genomic instability, angiogenesis, and epithelial barrier destruction and metabolic regulation. These pathophysiological changes could result in oral cancer. Rising evidence suggests that oral dysbacteriosis and particular microbes may play a positive role in the evolution, development, progression, and metastasis of oral cancer, for instance, oral squamous cell carcinoma (OSCC) through direct or indirect action.

Effectiveness of low level laser therapy versus cryotherapy in cancer patients with oral mucositis: Systematic review and network meta-analysis

OBJECTIVE

The purpose of this network meta-analysis was to analyze the relative effects of low level laser therapy (LLLT) and/or cryotherapy in cancer patients with oral mucositis (OM).

METHODS

This literature search followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines using MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials (CENTRAL), and the Physiotherapy Evidence Database (PEDro) up to 2020. Only randomized control trials which involved comparisons of groups receiving the interventions of combined cryotherapy and LLLT, LLLT, cryotherapy and usual care (the control group) in patients with cancer were eligible for inclusion. The effect sizes are presented as odds ratios for the occurrence of severe, moderate and none/mild OM. The mixed treatment comparison was conducted using generalized linear mixed models to analyze the direct and indirect comparisons of interventions. The critical appraisal was assessed using Cochrane Collaboration's tool. Heterogeneity between studies was assessed using I² statistics, and publication bias was evaluated by constructing a funnel plot.

RESULTS

Twenty-six randomized controlled trials with a total enrollment of 1830 cancer patients with OM were included. The outcome of none/mild OM is desirable, and odds ratios of more than 1 favor the intervention group. Moderate and severe OM are defined as adverse outcomes, and ORs less than 1 favor the intervention group. The treatment effects of the combined cryotherapy and LLLT were better than those of usual care for none/mild and severe OM (ORs = 106.23 [95% CI = 12.15 to 929.17] and 0.01 [95% CI = 0 to 0.57], respectively). Treatment effects with cryotherapy alone and LLLT alone were better than those with usual care for none/mild and severe OM (ORs = 3.13 [95%CI = 1.56 to 6.27]; ORs = 7.56 [95%CI = 3.84 to 14.88] and 0.25 [95%CI = 0.11 to 0.54]; ORs = 0.13 [95%CI = 0.07 to 0.24], respectively). Nevertheless, for patients with none/mild OM, treatment effects with combined use of cryotherapy and LLLT were better than those with only LLT or cryotherapy (ORs = 14.06 [95%CI = 1.79 to 110.30] and 33.95 [95%CI = 3.50 to 329.65], respectively). For patients with moderate OM, treatment effect did not reach statistical significance among comparisons. The limitations include the wide variability in treatment protocols and the non-uniform outcome measurements across the studies examined.

CONCLUSION

Compared with no intervention, the treatment effects of combined cryotherapy and LLLT, laser alone, and cryotherapy alone are beneficial for the reduction of severe OM. There is no difference in treatment effects among cryotherapy and/or LLLT intervention in cancer patients with moderate OM. Results of this study provide an implicative basis for LLLT and cryotherapy as viable interventions that can significantly improve severe OM.

The combination of traditional and auricular acupuncture to prevent xerostomia and anxiety in irradiated patients with HNSCC: a preventive, parallel, single-blind, 2-arm controlled study

OBJECTIVE

The purpose of the present study was to investigate the effect of acupuncture on xerostomia in irradiated patients with head and neck squamous cell carcinoma (HNSCC).

STUDY DESIGN

A preventive, 2-arm, parallel, single-blind trial was performed. Patients with HNSCC (N = 296) were checked for eligibility, and 107 patients were enrolled in the study. The study comprised 1 group that did not receive the intervention (n = 55) and the interventional group that received traditional and auricular acupuncture (n = 52). The primary outcome was the reduction of the patients' xerostomia after treatment. In addition, the secondary outcome was the reduction of anxiety.

RESULTS

The current acupuncture protocol reduced the xerostomia score and increased saliva volume and density without changing salivary pH. Additionally, acupuncture decreased the Beck Anxiety Inventory (BAI) score after radiation therapy.

CONCLUSION

Combining traditional and auricular acupuncture reduced xerostomia and increased saliva volume without changing the saliva's pH in irradiated patients with HNSCC. Additionally, the combination of traditional and auricular acupuncture reduced BAI scores.

Primary evaluation of an air-cooling device to reduce oral mucositis: a pilot study in healthy volunteers

Oral mucositis is a common side effect of chemo and radiotherapy causing painful ulcers in the oral mucosa. One of the preventive treatments recommended in international guidelines is oral cryotherapy (OC). Randomized clinical trials on OC have used ice and ice-chips to cool the mouth, but this cooling method can be difficult for the patients to tolerate. Studies have shown that OC with ice for a period of 60 min reduces the oral temperature by 12.9 °C. The aim of this pilot study was to evaluate the temperature reduction and tolerability of OC using an intra-oral air-cooling (IOAC) device in healthy volunteers. Twelve healthy volunteers, mean age 35.4 years, were included in the study. They were treated with OC using the IOAC device for 60 min. Measurements of temperature were obtained at baseline, 5 and 60 min using a FLIR® C2 camera. After the OC session, tolerability and adverse events were documented using a questionnaire. All participants were able to use the device for 60 min. The overall temperature reduction after 5 min of OC was 10.7°C (p < 0.01) and after 60 min 14.5°C (p < 0.01). The most common adverse events were bad fit of the mouthpiece (n = 6), hypersalivation (n = 6), and difficulties swallowing (n = 5). The oral device reduced the temperature of the oral mucosa as much as treatment with ice with tolerable adverse events. The mouthpiece will be remodeled to improve tolerability before further studies are conducted.

Use of a natural multicomponent mouthwash plus oral hygiene vs oral hygiene alone to prevent everolimus-induced stomatitis: the STOP multicenter, randomized trial

BACKGROUND

Stomatitis is highly prevalent in patients with cancer treated with the mammalian target of rapamycin inhibitor everolimus; it usually has an early onset and may compromise treatment dose intensity and patients' quality of life. Within the randomized controlled Stomatitis Prevention trial (STOP, ISRCTN14568888), we investigated the possibility of using a commercial natural multicomponent mouthwash (Orasol Plus®) to prevent the development of stomatitis of any grade in patients with advanced renal cell carcinoma (RCC) treated with everolimus.

METHODS

Overall, 62 patients were randomized to receive either Orasol Plus in addition to oral hygiene or oral hygiene alone (31 patients per treatment arm).

RESULTS

In the whole study population, 28 episodes of stomatitis were observed (41.9%); in only 2 patients, stomatitis occurred more than once (2 episodes). As expected, the episodes of stomatitis occurred early in the course of treatment with everolimus. Treatment with Orasol Plus prevented the onset of everolimus-induced stomatitis: only 8 episodes of stomatitis were observed in the treated group with Orasol Plus in addition to oral hygiene vs 20 episodes in the group treated with oral hygiene only (p = 0021). Also, a reduction in the average duration of mucositis in patients treated with Orasol Plus compared to patients treated with oral hygiene only was observed (8 days vs 11.2 days, p = 0.0416).

CONCLUSION

This study showed that the use of a natural multicomponent mouthwash coupled with regular oral hygiene was able to reduce the severity and duration of everolimus-induced stomatitis in patients with RCC.

TRIAL REGISTRATION NUMBER

ISRCTN14568888.

Systematic review of oral cryotherapy for the management of oral mucositis in cancer patients and clinical practice guidelines

PURPOSE

To update the 2013 Multinational Association of Supportive Care in Cancer/International Society of Oral Oncology (MASCC/ISOO) clinical practice guidelines on oral cryotherapy for the management of oral mucositis (OM) caused by cancer therapies.

METHODS

A systematic review was conducted by the Mucositis Study Group of MASCC/ISOO. The evidence for each intervention for specific cancer treatment modalities was assigned a level of evidence (LoE). The findings were added to the database used to develop the 2013 MASCC/ISOO clinical practice guidelines. Based on the LoE, the guidelines were set as: recommendation, suggestion, or no guideline possible.

RESULTS

A total of 114 papers were identified: 44 from PubMed and 70 from Web of Science. After abstract triage and merging with the 2013 database, 36 papers were reviewed. The LoE for prevention of OM with oral cryotherapy in patients undergoing autologous hematopoietic stem cell transplant using high-dose melphalan conditioning protocols was upgraded, and the guideline changed to recommendation. Additionally, the recommendation for prevention of OM with oral cryotherapy in patients receiving bolus 5-fluorouracil for the treatment of solid tumors was confirmed. No guidelines were possible for other clinical settings.

CONCLUSIONS

The evidence supports recommendations for the use of oral cryotherapy for the prevention of OM for either (i) patients undergoing autologous hematopoietic stem cell transplant with high-dose melphalan conditioning protocols or (ii) patients receiving bolus 5-fluorouracil chemotherapy.

Oral cryotherapy for oral mucositis management in patients receiving allogeneic hematopoietic stem cell transplantation: a prospective randomized study

PURPOSE

To explore the best schedule of oral cryotherapy for the prevention of oral mucositis in recipients of myeloablative hematopoietic stem cell transplantation (HSCT).

METHODS

A prospective randomized study was conducted to recruit allogeneic HSCT recipients, who were then randomly allocated into four arms to accept the following: oral cryotherapy during the whole course (arm A) or second half of the course (arm B) of cytotoxic agents administration, regular oral cryotherapy twice a day (arm C), or conventional oral care without cryotherapy (arm D). Status of oral mucositis was daily assessed from the first day of conditioning to the 15th day post-HSCT. A myeloablative conditioning regimen was used which was composed of busulfan, cyclophosphamide, and cytarabine.

RESULTS

Totally 160 cases were consecutively enrolled in this study, and 145 cases were eligible for oral mucositis assessment. Both arm A and arm B were associated with a lower incidence and short duration of severe mucositis (≥ grade 3), although no statistical difference was found between these two groups (p = 0.463, p = 0.678). The highest incidence of severe mucositis was observed in arm C. Recovery of mucositis also had a significant diversity among the 4 arms (F = 4.133, p = 0.008).

CONCLUSIONS

Risk and outcome of severe oral mucositis could be ameliorated by oral cryotherapy during the administration of cytotoxic agents for allogeneic HSCT patients receiving non-radiation myeloablative conditioning regimen, and a half-course schedule could acquire a comparable efficacy compared with the whole-course schedule.

A Comparison of the Conditioning Regimens BEAM and FEAM for Autologous Hematopoietic Stem Cell Transplantation in Lymphoma: An Observational Study on 1038 Patients From Fondazione Italiana Linfomi

BEAM (carmustine [bis-chloroethylnitrosourea (BCNU)]-etoposide-cytarabine-melphalan) chemotherapy is the standard conditioning regimen for autologous stem cell transplantation (ASCT) in lymphomas. Owing to BCNU shortages, many centers switched to fotemustine-substituted BEAM (FEAM), lacking proof of equivalence. We conducted a retrospective cohort study in 18 Italian centers to compare the safety and efficacy of BEAM and FEAM regimens for ASCT in lymphomas performed from 2008 to 2015. We enrolled 1038 patients (BEAM = 607, FEAM = 431), of which 27% had Hodgkin lymphoma (HL), 14% indolent non-Hodgkin lymphoma (NHL), and 59% aggressive NHL. Baseline characteristics including age, sex, stage, B-symptoms, extranodal involvement, previous treatments, response before ASCT, and overall conditioning intensity were well balanced between BEAM and FEAM; notable exceptions were median ASCT year (BEAM = 2011 versus FEAM = 2013, P < .001), Sorror score ≥3 (BEAM = 15% versus FEAM = 10%, P = .017), and radiotherapy use (BEAM = 18% versus FEAM = 10%, P < .001). FEAM conditioning resulted in higher rates of gastrointestinal and infectious toxicities, including severe oral mucositis grade ≥3 (BEAM = 31% versus FEAM = 44%, P < .001), and sepsis from Gram-negative bacteria (mean isolates/patient: BEAM = .1 versus FEAM = .19, P < .001). Response status at day 100 post-ASCT (overall response: BEAM = 91% versus FEAM = 88%, P = .42), 2-year overall survival (83.9%; 95% confidence interval [CI], 81.5% to 86.1%) and progression-free survival (70.3%; 95% CI, 67.4% to 73.1%) were not different in the two groups. Mortality from infection was higher in the FEAM group (subhazard ratio, 1.99; 95% CI, 1.02 to 3.88; P = .04). BEAM and FEAM do not appear different in terms of survival and disease control. However, due to concerns of higher toxicity, fotemustine substitution in BEAM does not seem justified, if not for easier supply.

Treatment of mucositis with combined 660- and 808-nm-wavelength low-level laser therapy reduced mucositis grade, pain, and use of analgesics: a parallel, single-blind, two-arm controlled study

Oral squamous cell carcinoma (OSCC) is the most frequent oral malignant neoplasia. As consequence of OSCC treatment, oral mucositis (OM) is one of the most common adverse effects of OSCC treatment. Currently, there is no consensus for OM treatment. The purpose of the current study was to test the combination of red and infrared low-level laser therapy (LLLT) for OM treatment. Primary culture of human fibroblast was performed to identify LLLT dose. After laboratory tests, a two-arm parallel, single-blind, controlled study was conducted. The two arms were group 1, both 660- and 808-nm wavelengths (300 J/cm², 9 J of total energy, 100 mW, spot size 3 mm²), and group 2, only 660-nm wavelength (300 J/cm², 9 J of total energy, 100 mW, spot size 3 mm²). Both treatments were performed twice a week. Group 1 presented a reduction of mucositis grade in comparison to group 2. Group 1 also presented reduction of analgesics prescription. But no significant differences between groups 1 and 2 were observed according to the pain scale. In conclusion, the current study demonstrated that a combination of red and infrared at a higher dose (300 J/cm²) reduced both oral mucositis grade and analgesics prescription. The effects of the combination of RT and LLLT are unclear and need more studies.

Challenges in the local delivery of peptides and proteins for oral mucositis management

Oral mucositis, a common inflammatory side effect of oncological treatments, is a disorder of the oral mucosa that can cause painful ulcerations, local motor disabilities, and an increased risk of infections. Due to the discomfort it produces and the associated health risks, it can lead to cancer treatment restrains, such as the need for dose reduction, cycle delays or abandonment. Current mucositis management has low efficiency in prevention and treatment. A topical drug application for a local action can be a more effective approach than systemic routes when addressing oral cavity pathologies. Local delivery of growth factors, antibodies, and anti-inflammatory cytokines have shown promising results. However, due to the peptide and protein nature of these novel agents, and the several anatomic, physiological and environmental challenges of the oral cavity, their local action might be limited when using traditional delivering systems. This review is an awareness of the issues and strategies in the local delivery of macromolecules for the management of oral mucositis.

Interventions for preventing oral mucositis in patients with cancer receiving treatment: oral cryotherapy

BACKGROUND

Oral mucositis is a side effect of chemotherapy, head and neck radiotherapy, and targeted therapy, affecting over 75% of high risk patients. Ulceration can lead to severe pain and difficulty eating and drinking, which may necessitate opioid analgesics, hospitalisation and nasogastric or intravenous nutrition. These complications may lead to interruptions or alterations to cancer therapy, which may reduce survival. There is also a risk of death from sepsis if pathogens enter the ulcers of immunocompromised patients. Ulcerative oral mucositis can be costly to healthcare systems, yet there are few preventive interventions proven to be beneficial. Oral cryotherapy is a low-cost, simple intervention which is unlikely to cause side-effects. It has shown promise in clinical trials and warrants an up-to-date Cochrane review to assess and summarise the international evidence.

OBJECTIVES

To assess the effects of oral cryotherapy for preventing oral mucositis in patients with cancer who are receiving treatment.

SEARCH METHODS

We searched the following databases: the Cochrane Oral Health Group Trials Register (to 17 June 2015), the Cochrane Central Register of Controlled Trials (CENTRAL) (Cochrane Library 2015, Issue 5), MEDLINE via Ovid (1946 to 17 June 2015), EMBASE via Ovid (1980 to 17 June 2015), CANCERLIT via PubMed (1950 to 17 June 2015) and CINAHL via EBSCO (1937 to 17 June 2015). We searched the US National Institutes of Health Trials Registry, and the WHO Clinical Trials Registry Platform for ongoing trials. No restrictions were placed on the language or date of publication when searching databases.

SELECTION CRITERIA

We included parallel-design randomised controlled trials (RCTs) assessing the effects of oral cryotherapy in patients with cancer receiving treatment. We used outcomes from a published core outcome set registered on the COMET website.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened the results of electronic searches, extracted data and assessed risk of bias. We contacted study authors for information where feasible. For dichotomous outcomes, we reported risk ratios (RR) and 95% confidence intervals (CI). For continuous outcomes, we reported mean differences (MD) and 95% CIs. We pooled similar studies in random-effects meta-analyses. We reported adverse effects in a narrative format.

MAIN RESULTS

We included 14 RCTs analysing 1280 participants. The vast majority of participants did not receive radiotherapy to the head and neck, so this review primarily assesses prevention of chemotherapy-induced oral mucositis. All studies were at high risk of bias. The following results are for the main comparison: oral cryotherapy versus control (standard care or no treatment). Adults receiving fluorouracil-based (5FU) chemotherapy for solid cancersOral cryotherapy probably reduces oral mucositis of any severity (RR 0.61, 95% CI 0.52 to 0.72, 5 studies, 444 analysed, moderate quality evidence). In a population where 728 per 1000 would develop oral mucositis, oral cryotherapy would reduce this to 444 (95% CI 379 to 524). The number needed to treat to benefit one additional person (NNTB), i.e. to prevent them from developing oral mucositis, is 4 people (95% CI 3 to 5).The results were similar for moderate to severe oral mucositis (RR 0.52, 95% CI 0.41 to 0.65, 5 studies, 444 analysed, moderate quality evidence). NNTB 4 (95% CI 4 to 6).Severe oral mucositis is probably reduced (RR 0.40, 95% CI 0.27 to 0.61, 5 studies, 444 analysed, moderate quality evidence). Where 300 per 1000 would develop severe oral mucositis, oral cryotherapy would reduce this to 120 (95% CI 81 to 183), NNTB 6 (95% CI 5 to 9). Adults receiving high-dose melphalan-based chemotherapy before haematopoietic stem cell transplantation (HSCT)Oral cryotherapy may reduce oral mucositis of any severity (RR 0.59, 95% CI 0.35 to 1.01, 5 studies, 270 analysed, low quality evidence). Where 824 per 1000 would develop oral mucositis, oral cryotherapy would reduce this to 486 (95% CI reduced to 289 to increased to 833). The NNTB is 3, although the uncertainty surrounding the effect estimate means that the 95% CI ranges from 2 NNTB, to 111 NNTH (number needed to treat in order to harm one additional person, i.e. for one additional person to develop oral mucositis).The results were similar for moderate to severe oral mucositis (RR 0.43, 95% CI 0.17 to 1.09, 5 studies, 270 analysed, low quality evidence). NNTB 3 (95% CI 2 NNTB to 17 NNTH).Severe oral mucositis is probably reduced (RR 0.38, 95% CI 0.20 to 0.72, 5 studies, 270 analysed, moderate quality evidence). Where 427 per 1000 would develop severe oral mucositis, oral cryotherapy would reduce this to 162 (95% CI 85 to 308), NNTB 4 (95% CI 3 to 9).Oral cryotherapy was shown to be safe, with very low rates of minor adverse effects, such as headaches, chills, numbness/taste disturbance, and tooth pain. This appears to contribute to the high rates of compliance seen in the included studies.There was limited or no evidence on the secondary outcomes of this review, or on patients undergoing other chemotherapies, radiotherapy, targeted therapy, or on comparisons of oral cryotherapy with other interventions or different oral cryotherapy regimens. Therefore no further robust conclusions can be made. There was also no evidence on the effects of oral cryotherapy in children undergoing cancer treatment.

AUTHORS' CONCLUSIONS

We are confident that oral cryotherapy leads to large reductions in oral mucositis of all severities in adults receiving 5FU for solid cancers. We are less confident in the ability of oral cryotherapy to reduce oral mucositis in adults receiving high-dose melphalan before HSCT. Evidence suggests that it does reduce oral mucositis in these adults, but we are less certain about the size of the reduction, which could be large or small. However, we are confident that there is an appreciable reduction in severe oral mucositis in these adults.This Cochrane review includes some very recent and currently unpublished data, and strengthens international guideline statements for adults receiving the above cancer treatments.