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high relevance mucositis toxicity RCT

Lithium mouthwash reduced severe oral mucositis during head and neck radiotherapy

Lithium mouthwash reduced severe oral mucositis from 52.1% to 34.2% in a randomized phase II head and neck radiotherapy trial.

RadOncToday · ·1 min read

KEY POINTS

  • This prospective single-center phase I/II study enrolled 175 patients with nonmetastatic head and neck cancer receiving definitive or postoperative radiotherapy: 15 entered phase I dose escalation and 160 entered the randomized phase II component. Phase II compared lithium-containing mouthwash with matched placebo in a double-blind 1:1 design.
  • Phase I established 0.15 mol/L lithium as the recommended concentration. During phase II, patients used the mouthwash three times daily throughout radiotherapy; the per-protocol efficacy population included 73 lithium-treated and 71 placebo-treated patients.
  • The primary endpoint, WHO grade 3–4 severe oral mucositis, occurred in 34.2% with lithium versus 52.1% with placebo (P=.0304), an absolute reduction of 17.9 percentage points and roughly one-third relative reduction. Median time to severe mucositis was not reached with lithium versus 35.0 days with placebo (P=.0262).
  • Severe mucositis also appeared shorter when it occurred: mean duration was 9.4 days versus 19.4 days, although this difference narrowly missed statistical significance (P=.0575). Overall mucositis burden during treatment was lower, with mean mucositis total-score AUC 5.1 versus 7.4 (P<.001).
  • Taste dysfunction was common in both groups, but lithium provided an early signal of protection. At mid-radiotherapy, objective taste dysfunction occurred in 63.0% versus 78.9% (P=.0363), and mean chemical taste scores were 6.9 versus 4.1 (P=.0066); by the end of radiotherapy and one month later, the chemical taste-score advantage was no longer significant.
  • Grade ≥2 dry mouth occurred in 55.8% versus 70.4% (P=.0528), a numerical but nonsignificant reduction. Lithium-treated patients also reported less fatigue, pain and swallowing impairment, whereas analgesic use, nutritional supplementation and treatment-related weight change were similar between groups.
  • Overall adverse-event incidence and severity were similar, with no severe adverse event attributed to lithium mouthwash. Mild nausea, vomiting and unpleasant metallic taste were reported; the authors emphasize the single-center phase II design, limited durability of the taste effect and absence of mechanistic biomarkers as reasons for further phase III validation.

CLINICAL TAKEAWAY

A simple topical lithium mouthwash reduced severe oral mucositis by almost 18 absolute percentage points during head and neck radiotherapy, with no major safety signal. The randomized design makes this clinically compelling supportive-care evidence, but a multicenter phase III trial is needed before routine adoption.

SOURCE

International Journal of Radiation Oncology, Biology, Physics