1. Introduction
Oral mucosal epithelial cells are extremely sensitive to damage caused by chemoradiotherapy, and oral mucositis (OM) is a common adverse prognostic event in patients receiving hematopoietic autologous stem cell transplantation (ASCT) after high-dose chemotherapy or radiotherapy, and different treatment options directly affect the clinical symptoms of OM. [ 1 , 2 ] Clinical symptoms of OM include mild erythema, edema, pain, extreme pain, and even ulceration; severe OM can affect the patient’s ability to speak, eat, and swallow and even lead to dehydration, malnutrition, and eventually serious infection. [ 3 ] Severe mucositis has been shown to correlate with overall survival by ASCT ( P = .002). [ 4 ] Prevention or early intervention of high-incidence OM in ASCT patients is necessary to improve survival in ASCT patients. [ 5 ]
High-dose melphalan (MEL) combined with ASCT is currently the first choice for the treatment of multiple myeloma (MM), which has the characteristics of high efficiency, low recurrence rate, and prolongation of disease-free survival. [ 6 ] As a cytotoxic drug, MEL can reduce mitosis in epithelial cells, resulting in cell contraction or apoptosis, mucosal shedding, and bacteria, viruses, or fungi invading the oral wall, which also makes it the most important factor in inducing OM in ASCT patients. [ 7 ] The Multinational Association of Supportive Care in Cancer/International Society of Oral Oncology guidelines state that oral care during melphalan administration and improved oral hygiene can minimize the occurrence or severity of OM. [ 8 , 9 ]
Modified oral care can maintain patients’ good oral hygiene, reduce oral bacterial colonization, and improve quality of life. This study aimed to investigate the prevention of OM in MM patients receiving high-dose MEL chemotherapy before ASCT with different mouthwashing methods.
Nonetheless, despite continuous progress in supportive care for hematologic malignancies, the effectiveness of oral care interventions during ASCT remains inconsistent. Recent studies have mainly focused on pharmacological or mouthwash-based strategies – such as zinc chloride, Nigella sativa oil, or vitamin E–containing formulations – to alleviate chemotherapy-induced OM. [ 8 , 9 ] However, these investigations have primarily addressed the composition of oral rinses rather than the procedural aspects of oral care itself.
Current protocols generally specify which mouthwash to use but rarely standardize how oral hygiene should be performed. Critical factors – including gargling duration, involvement of the oropharynx, and the quality of the gargling technique – are seldom defined, even though they may strongly influence preventive efficacy. Moreover, inconsistent patient education and limited nursing supervision often result in poor adherence, potentially increasing the risk and severity of OM.
To date, few studies have systematically evaluated the effect of standardized gargling techniques combined with nurse-supervised instruction in patients undergoing high-dose melphalan conditioning and ASCT. Addressing this gap, the present study retrospectively investigates an enhanced, procedure-based oral care model aimed at improving the prevention of OM and supporting better clinical outcomes in this patient population.
2. Materials and methods
This study was approved by the Ethics Committee of the First Affiliated Hospital of Soochow University. This retrospective observational study involved patients with MM treated with ASCT in the Hematology Department of the First Affiliated Hospital of Soochow University from December 2019 to February 2022. The study aimed to evaluate the effectiveness of various oral care regimens during the high-dose conditioning phase of MEL to prevent and manage OM, a common and unfortunate complication of ASCT.
A total of 87 patients met the following eligibility criteria: a confirmed diagnosis of MM according to the International Myeloma Working Group criteria; age between 40 and 70 years; and eligibility for high-dose melphalan conditioning followed by ASCT.
Patients were excluded if they had: active oral or maxillofacial lesions, plasma cell neoplasms involving or adjacent to oral structures; a history of head or neck radiotherapy; severe hepatic, renal, or cardiac dysfunction; active infection at the time of conditioning; or uncontrolled diabetes or other systemic comorbidities that could interfere with mucosal healing. Baseline oral health was assessed before conditioning, including evaluation of oral hygiene status, presence of caries, periodontal disease, or mucosal injury. When necessary, dental cleaning and treatment of preexisting oral conditions were completed before initiation of chemotherapy. Patients who had previously received intensive chemotherapy or radiotherapy within 3 months before ASCT were also excluded to minimize confounding effects on OM risk.
All patients provided written informed consent at the time of transplantation, and the study protocol was approved by the Ethics Committee of the First Affiliated Hospital of Soochow University. This study was designed as a retrospective observational analysis. During the study period, 2 different oral care protocols were implemented in routine clinical practice as part of quality improvement efforts. Based on the oral care regimen that each patient actually received during their hospitalization, patients were retrospectively categorized into the control group (routine oral care, n = 49) or the observation group (enhanced oral care, n = 38) (Table 1 ). All patients received intravenous high-dose melphalan (140 mg/m 2 or 200 mg/m 2 ) as conditioning therapy, and oral care interventions were performed from the start of the conditioning phase and continued throughout the treatment period.
Table 1
Oral care patterns in 2 groups.
| Care plan | Control group | Observation group |
| Wake up in the morning before going to bed | Use chlorhexidine acetate mouthwash with a sponge stick to brush your teeth. | Use chlorhexidine acetate mouthwash with a sponge stick to brush your teeth. |
| Before meals | Rinse your mouth with warm water. | Rinse your mouth with warm water. |
| After meals | Gargle alternately after meals with warm water or 0.9% saline, nystatin and 5% sodium bicarbonate solution. | Gargle alternately after meals with warm water or 0.9% saline, nystatin, and 5% sodium bicarbonate solution. |
| Medication | Gargle and swallow the rehabilitation solution every day, 3 times a day, 5-10 mL each time. | Gargle and swallow the rehabilitation solution every day, 3 times a day, 5–10 mL each time. |
| Cryotherapy | Patients need to have ice in the mouth twice a day for 5–10 min each time. Continue to contain ice in the mouth on the day of the infusion, for example, infusion of melphalan for 2 h and oral ice for 2 h. | Patients need to have ice in the mouth twice a day for 5–10 min each time. Continue to contain ice in the mouth on the day of the infusion, for example, infusion of melphalan for 2 h and oral ice for 2 h. |
| Gargle method | 15–30 mL mouthwash, gargle for 10 s. | 15–30 mL mouthwash each time, gargle for 30 s, puff up 10–15 times, gargle 2–3 times each time to complete 1 gargle. Raise your head and make an “ah” sound so that the mouthwash fully touches your throat. If you cannot raise your head to rinse your mouth, do not forcibly raise your head to rinse your mouth to avoid choking. |
| Evaluation method | 1. Ask the patient what type of mouthwash they use and how long to use it. | |
| 2. Ask the patient to demonstrate a live gargle. | ||
| 3. Correct the patient’s mouth gargle error in time. | ||
| 4. If the patient is older or uncooperative, the bed nurse needs to accompany the patient to watch the video repeatedly and practice repeatedly. |
2.1. Oral care interventions
Both groups adhered to standard oral hygiene practices, which involved washing the mouth with chlorhexidine acetate mouthwash rinsed with warm water before meals and brushing teeth with a sponge stick containing chlorhexidine acetate mouthwash upon awakening and before bed, as well as warm water rinsed before meals. After every meal, all patients were gargled in a rotation of warm water, 0.9% saline solution, nystatin, and 5% sodium bicarbonate solution. In addition, 3 times a day, patients gargled and swallowed a rehabilitation solution (5–10 mL). Cryotherapy was also applied twice a day and during MEL infusion, where patients were instructed to keep ice in their mouth for 5 to 10 minutes to minimize the risk of damage to the mucosa. The major difference between the 2 groups was the technique of gargling, reported in Table 1 . Briefly, participants in the control group gargled for 10 seconds with 15 to 30 mL of mouthwash, while the participants in the observation group utilized a more enhanced technique by gargling for 30 seconds while puffing their cheeks 10 to 15 times, which the rinse was repeated 2 to 3 times, and with the head raised while vocalizing “ah,” to encourage deeper contact with the oropharynx. For patients unable to raise their heads, other methods of assisting them took place with nurses to prevent choking.
The nursing staff observed patient adherence and technique using an oral care evaluation protocol (Table 2 ) encompassing direct inquiry, real-time demonstration, and corrective instruction. Elderly or nonadherent patients received ongoing exposure to video instruction and hands-on coaching provided by the nursing staff. All patients received an oral health assessment prior to chemotherapy to identify signs of infection, trauma, or lesions. When warranted, ultrasonic scaling and polishing were performed, caries were addressed, and patient oral hygiene was reinforced using the modified Stillman brushing method. For patients unable to brush independently, under direct supervision by nursing staff, a cotton swab was used to clean periodontal deposits to avoid further injury.
Table 2
Routine oral care measures.
BID = bis in die (twice daily).
| Oral problems | Mode of care |
| Throat redness/sore throat | Citrulli degelatinatum and cydiodine buccal tablets are taken in the mouth. |
| Throat redness/sore throat with pharyngeal obstruction | Add 2% lidocaine solution to gargle and swallow, microwave BID. |
| Throat redness/sore throat with pharyngeal and esophageal obstruction | Follow the doctor’s advice to add intravenous pain medication and microwave irradiation BID. |
2.2. Assessment of oral mucositis
The World Health Organization Oral Toxicity Scale was used to grade the OM using an ordinal scale of Grade 0 to Grade 4, with Grade 0 being no mucositis and Grade 4 being severe ulceration interfering with alimentation. Trained nurses did daily assessments throughout hospitalization for transplant. OM treatment was based on clinical presentation: For ulcers: topical ulcer paste and compound solutions; For ulcer-related pain: 2% lidocaine rinse, nutritional support, intravenous analgesia as needed; For Grade 3 OM: oral irrigation with saline every 2 to 3 hours and initiation of oral enteral nutrition. Patients with complications associated with the pharynx or esophagus had focused syllabi in topical treatments, as microwave will were occupied for symptom-related medications (data not shown). Treatment approaches are detailed in Table 3 .
Table 3
General information about the patients.
MEL = melphalan.
| Indexes | Control group | Observation group | t /χ 2 | P |
| Gender, N (%) | ||||
| Male | 27 (55.1) | 20 (52.6) | 0.053 | .832 |
| Female | 22 (44.9) | 18 (47.4) | ||
| Age, ( x ¯ ± s ) | 55.86 ± 1.04 | 57.21 ± 1.07 | -0.895 | .539 |
| Length of hospital stay, ( x ¯ ± s ) | 21.76 ± 0.63 | 19.53 ± 0.33 | 2.868 | .006 |
| Weight changes, ( x ¯ ± s ) | 4.24 ± 0.20 | 2.51 ± 0.16 | 6.427 | .023 |
| Number of transplanted cells, ( x ¯ ± s ) | 4199948.98 ± 341959.52 | 4394768.42 ± 379886.55 | -0.380 | .915 |
| MEL dose, N (%) | ||||
| 140 mg/m 2 | 12 (24.5) | 4 (10.5) | 2.780 | .162 |
| 200 mg/m 2 | 37 (75.5) | 34 (89.5) |
2.3. Data collection and statistical analysis
The data collected included patient demographics (age, gender, and length of hospital stay), transplant-related data (number of transplanted cells and neutrophil levels), treatment data (medication regimen and weight change), and oral mucositis-related data (time to onset, time to healing, and grade). Pain and nutritional data were also collected on validated scales. Statistical analyses were conducted on SPSS version 23.0 (IBM Corp., Armonk ). Continuous variables were expressed as mean ± standard deviation and analyzed with independent-samples t test. Categorical variables were expressed as count and percent and analyzed with a chi-square (χ 2 ) test. A P value of less than .05 was considered statistically significant.
3. Result
3.1. Comparison of baseline characteristics
Table 3 reveals no significant differences in baseline characteristics, including sex, age, number of transplanted cells, and MEL dosage ( P > .05), between the control and observation groups, suggesting that the 2 groups were similar at baseline. Conversely, the observation group had a significantly shorter hospitalization time than the control group ( P < .05). Additionally, while both groups lost weight during hospitalization, the weight change in the observation group was significantly less than in the control group ( P < .05; Table 3 ). General characteristics of the control and observation groups.
3.2. Comparison of neutrophil values and oral mucositis outcomes
According to Table 4 , neutrophil counts at transplantation did not differ significantly between the 2 groups (1.09 ± 0.29 × 10⁹/L vs 0.92 ± 0.22 × 10⁹/L, P = .088). However, at OM healing, the control group showed higher neutrophil levels than the observation group (5.93 ± 0.88 × 10⁹/L vs 3.67 ± 0.40 × 10⁹/L, P = .033). The onset time of OM after transplantation was similar between groups (4.31 ± 0.22 vs 4.67 ± 0.21 days, P = .215).
Table 4
Clinical indicators of the patient.
OM = oral mucositis.
| Indexes | Control group | Observation group | t / χ 2 | P |
| Patient transplant days when OM occurs, ( x ¯ ± s ) | 4.31 ± 0.22 | 4.67 ± 0.21 | −1.094 | .215 |
| Neutrophil values at transplantation, ( x ¯ ± s ) | 1.09 ± 0.29 | 0.92 ± 0.22 | 0.437 | .088 |
| Neutrophil values at the time of healing, ( x ¯ ± s ) | 5.93 ± 0.88 | 3.67 ± 0.40 | 1.942 | .033 |
| Number of OM patients, N (%) | ||||
| No OM occurred | 8 (16.3) | 14 (36.8) | 4.768 | .046 |
| OM occurred | 41 (83.7) | 24 (63.2) | ||
| Pain score, ( x ¯ ± s ) | 0.94 ± 0.15 | 0.74 ± 0.18 | 0.864 | .694 |
| OM degree score, ( x ¯ ± s ) | 1.49 ± 0.11 | 1.58 ± 0.15 | −0.532 | .692 |
| Nutritional score, ( x ¯ ± s ) | 3.04 ± 0.03 | 3.32 ± 0.14 | −2.211 | .000 |
| OM healing time, ( x ¯ ± s ) | 13.05 ± 0.13 | 11.17 ± 0.19 | 8.436 | .527 |
Fewer patients in the observation group developed OM compared with the control group (63.2% vs 83.7%, P = .046), suggesting a preventive benefit of enhanced oral care. Pain and OM severity scores were comparable between groups ( P > .05). The observation group demonstrated higher nutritional scores (3.32 ± 0.14 vs 3.04 ± 0.03, P < .001) and a slightly shorter OM healing time (11.17 ± 0.19 vs 13.05 ± 0.13 days, P = .527).
3.3. Comparison of pain, OM severity, nutritional score, and healing time
There were no significant differences in pain scores or OM severity scores between the 2 groups ( P > .05). However, the nutritional scores were significantly higher in the observation group compared to the control group ( P < .05), reflecting better nutritional status during recovery. Although OM healing time was not statistically different between the groups ( P > .05), the observation group showed a trend toward faster recovery. Figure 1 illustrates the condition of oral mucosa in the observation group before and after oral mucositis care, showing clear visual improvement.
4. Discussion
This study describes the efficacy of different oral care modalities for preventing OM in patients with MM during high-dose MEL combined with ASCT. We found that standardized gargling combined with drugs is more conducive to preventing OM in patients and can effectively reduce the degree of OM in patients. The main ways to prevent/treat OM include mouthwash cleaning, cryotherapy, etc.; mouthwashes containing sodium bicarbonate and normal saline can effectively play the role of preventing OM, and mouthwash formulations such as nystatin and chlorhexidine are often used together. [ 10 ] Studies have shown that zinc chloride mouthwash, [ 8 ] nigella sativa oil, [ 11 ] and drug combinations can also treat and reduce OM. In this study, multiple mouthwash patterns were used for 2 groups of patients, and the results showed that the combination of multiple mouthwashes could effectively prevent the incidence of post-transplant OM in MM patients and significantly improve the nutrition and weight of patients. Agha-Hosseini et al [ 12 ] similarly used combined mouthwash and showed significant results. The sodium bicarbonate mouthwash used in this study can quickly change the oral pH value to reach alkaline, destroy the fungal growth environment, and effectively inhibit the growth of fungi. [ 9 ] Nystatin is a broad-spectrum antifungal agent and membrane permeability enhancer, and increasing the dose does not affect its safety, and the combination of sodium bicarbonate is more effective in preventing OM. [ 13 , 14 ] Therefore, choosing a combined mouthwash with significant efficacy and compatible medicinal properties for alleviating OM is of great significance.
In this study, the normative or nonstandard mouth gargling was innovatively evaluated, the observation group followed the standard gargle care for 30 seconds, and the results showed that the number of patients with OM in the observation group was significantly lower ( P < .05) than that in the control group. The tonsils and posterior pharyngeal wall flushing are of great significance for removing bacteria and viruses. [ 15 ] In addition, studies have shown that the bulging cheek rinse method can cover the mouth and pharynx more comprehensively, and the gargling effect will be better than that of ordinary gargling at the same time. [ 16 ] Without gargling or short-term gargling, it is not enough to clean the posterior pharyngeal wall and tonsil fossa and effectively inhibit the growth of bacteria. [ 17 ] These are consistent with the results of this study, and standardizing the gargling time and gargling method is of great significance for preventing OM and improving the degree of OM in patients.
Given the effective therapeutic effect of cryotherapy on OM, this study innovatively combines cryotherapy with standardized mouthwash methods. The use of ice, cold water, and popsicles to cool the patient’s oral cavity during chemotherapy infusion can narrow blood vessels, reduce blood circulation in the oral cavity, and reduce the amount of chemotherapy drug that penetrates the mucous membrane, thereby reducing the risk of chemotherapy-induced OM. [ 18 ] After combining the standardized mouthwash method, we found that the recovery speed and recovery effect of OM in the observation group were better than those in the control group.
This study has some notable strengths. First, it is one of the few to investigate the combined effect of standardized gargling techniques and cryotherapy in a real-world cohort of ASCT patients with MM. Second, it investigates the possible usefulness of a nurse-supervised evaluation model for carrying out the oral care treatment to facilitate implementation and adherence to this enhanced protocol; this suggests that a structured education for patients and guided oral hygiene may offer promise in supportive cancer care. However, several limitations should be acknowledged. First, as a retrospective study, potential selection bias cannot be completely excluded, and unmeasured variables may have influenced both group allocation and clinical outcomes. Second, the relatively small sample size and single-center nature of this analysis may limit the generalizability of the findings. Third, other potential confounding factors – including differences in patient adherence to oral care protocols, variations in the use of supportive therapies such as cryotherapy or hematopoietic growth factors, and individual differences in nutritional status – could have also affected the incidence or recovery of OM. Additionally, variations in nursing staff experience and training may have influenced the consistency of intervention delivery. Future multicenter, prospective, and randomized studies with standardized implementation monitoring are warranted to further validate these findings and better control for patient- and institution-level confounders. Nevertheless, this study provides a meaningful foundation for understanding the potential benefits of enhanced oral care models in reducing OM risk among multiple myeloma patients undergoing high-dose melphalan and ASCT.
5. Conclusion
A better oral care protocol – incorporating improved gargling methods and monitored oral hygiene – was associated with a lower incidence of oral mucositis (OM) in patients with multiple myeloma undergoing high-dose melphalan and ASCT. These findings suggest a potential benefit of enhanced oral care practices in peri-transplant management, which should be further validated in larger, multicenter, and prospective studies.
Author contributions
Conceptualization: Qian Wu, Minghong Liu.
Data curation: Qian Wu, Xiaming Zhu, Minghong Liu.
Formal analysis: Qian Wu, Xiaming Zhu, Minghong Liu.
Investigation: Xiaming Zhu, Minghong Liu.
Methodology: Xiaming Zhu, Minghong Liu.
Validation: Qian Wu.
Visualization: Qian Wu, Minghong Liu.
Writing – original draft: Qian Wu, Xiaming Zhu, Minghong Liu.
Writing – review & editing: Qian Wu, Xiaming Zhu, Minghong Liu.
Abbreviations: ASCT autologous stem cell transplantation MEL melphalan MM multiple myeloma OM oral mucositis
Informed consent was obtained from all individual participants included in the study.
All procedures performed in studies involving human participants were in accordance with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. The Ethics Committee of The First Affiliated Hospital of Soochow University approves this study. Written informed consent was obtained.
The authors have no funding and conflicts of interest to disclose.
The datasets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request.
How to cite this article: Wu Q, Zhu X, Liu M. Effect of oral care models on the prevention of oral mucositis induced by high-doses of melphalan in patients undergoing ASCT. Medicine 2025;104:51(e46289).
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