Record ID: MS-N066 · Family: Supportive physical care / mucositis prevention · Clinical question: Does cooling the mouth with ice reduce oral mucositis during bolus 5-fluorouracil or high-dose melphalan treatment?
Evidence label: Recommended in specific short-infusion settings; not a universal mucositis strategy.
Evidence at a glance
- Benefit: Randomized evidence and guidelines support oral cryotherapy during bolus 5-fluorouracil and high-dose melphalan before autologous transplant.
- Certainty: Moderate for those specific regimens; low outside them.
- Risk: Cold intolerance, dental sensitivity, oral discomfort and rare tissue injury; some people cannot tolerate it.
- Cancer control: Not studied.
What was studied
In a classic randomized trial, 95 people receiving their first cycle of bolus 5-fluorouracil plus leucovorin were assigned to oral cryotherapy during drug administration or control care. Clinicians and patients assessed mucositis.
MASCC/ISOO guidelines and a Cochrane review were checked to determine where results have been replicated and translated into supportive-care recommendations. Contemporary studies also evaluate cryotherapy around high-dose melphalan used before autologous hematopoietic-cell transplantation.
What the results show
The 5-fluorouracil trial found substantially less mucositis with cryotherapy by physician assessment (P=.0002) and patient assessment (P=.0001). MASCC/ISOO guidance recommends oral cryotherapy during bolus 5-fluorouracil and suggests it with high-dose melphalan conditioning when feasible.
The mechanism—temporary local vasoconstriction during a short drug exposure—helps explain why this result should not be extrapolated to continuous infusions or unrelated regimens.
Limits and uncertainty
The early trial was small and predates many current supportive-care practices. Timing, ice delivery and chemotherapy pharmacokinetics matter. Evidence outside bolus 5-fluorouracil and high-dose melphalan is inconsistent or absent. The intervention prevents some mucositis; it does not guarantee prevention or treat established severe infection, dehydration or uncontrolled pain.
Safety and practical context
Only use a protocol approved by the oncology or transplant team. Cold-sensitive dental disease, oral wounds, Raynaud phenomenon, cryoglobulinemia, aspiration risk or inability to safely manage ice may make it unsuitable. Severe mouth pain, fever, inability to drink, uncontrolled bleeding or white plaques requires prompt clinical care. Maintain the prescribed oral-hygiene and pain-control plan.
Questions for the care team
- Does this exact chemotherapy schedule have evidence for oral cryotherapy?
- When should cooling start and stop under the center’s protocol?
- Are dental sensitivity, swallowing problems or cold-related conditions a contraindication?
Sources checked
- Randomized bolus 5-fluorouracil trial (PMID 1999715; DOI 10.1200/JCO.1991.9.3.449)
- MASCC/ISOO mucositis guideline (PMID 31836937)
- Cochrane review of oral cryotherapy (PMID 27583808)
- Randomized high-dose melphalan study (PMID 33084773)
Last literature search: October 18, 2026 · Record appraisal: October 18, 2026
Educational evidence summary, not personal medical advice. This record concerns symptom or supportive care. It does not establish tumor shrinkage, recurrence prevention or longer survival, and it should not delay or replace oncology treatment.
