Severe Oral Mucositis After Intensity-Modulated Radiation Therapy for Head and Neck Cancer.

Importance: Oral mucositis (OM) is a common and debilitating adverse effect observed in patients with head and neck cancer (HNC) receiving radiation therapy (RT). Previous studies examining associations between OM and clinical outcomes were performed in the era of 3-dimensional conformal RT planning with low rates of concurrent chemotherapy, and thus may not reflect current practice. Objective: To prospectively assess patient-reported OM and identify its associations with clinical outcomes and quality of life. Design, Setting, and Participants: This cohort study performed at a single institution included 702 consecutive patients who underwent definitive or adjuvant intensity-modulated RT (IMRT) for primary HNC from February 9, 2015, to May 27, 2022. Data were analyzed from November 28, 2022, to August 18, 2023. Main Outcomes and Measures: Severity of OM was assessed based on highest reported mouth and throat soreness (MTS) score during radiotherapy according to the Oral Mucositis Weekly Questionnaire-Head and Neck Cancer survey, which was administered weekly during IMRT. Linear mixed models were used to compare mean MTS scores grouped by disease site and chemotherapy regimen. Fisher exact tests and 1-way analysis of variance tests were performed to identify associations between severity of OM and clinical outcomes. Results: Among 576 eligible patients, the median age was 62.5 (IQR, 56.3-69.1) years, and 451 patients (78.3%) were men. In terms of race and ethnicity, 6 patients (1.0%) were American Indian or Alaska Native; 2 (0.3%), Asian; 31 (5.4%), Black; 8 (1.4%), Hispanic or Latino; 509 (88.4%), White; and 28 (4.9%), unknown. The most common treatment site was oropharynx (268 [46.5%]), and most patients received concurrent chemotherapy (464 [80.6%]). By the end of treatment, 360 patients (62.5%) developed severe OM and 568 (98.6%) developed some degree of OM. Linear mixed models found no significant differences in OM between HNC disease sites. Groups with greater highest severity of OM reported had higher rates of measured outcomes (listed respectively by MTS score 0, 1, 2, 3, and 4): feeding tube placement (0%, 3.6% [2 of 56], 6.6% [10 of 152], 14.7% [40 of 272], and 21.6% [19 of 88]; P = .001), hospitalization (12.5% [1 of 8], 10.7% [6 of 56], 15.1% [23 of 152], 23.9% [65 of 272], and 28.4% [25 of 88]; P = .02), opiate use (0%, 19.6% [11 of 56], 42.8%[65 of 152], 61.4% [167 of 272], and 64.8% [57 of 88]; P < .001) and experienced greater weight loss (median, -0.7 [IQR, -1.7 to -0.4] kg; median, 3.9 [IQR, 1.1 to 6.1] kg; median, 5.0 [IQR, 2.2 to 7.7] kg; median, 4.7 [IQR, 2.1 to 7.7] kg; and median, 7.7 [IQR, 2.8 to 10.6] kg; P < .001). Conclusions and Relevance: In this cohort study of patients with HNC, 62.5% developed severe OM. Higher severity of OM was associated with feeding tube placement, hospitalization, opiate use, and weight loss. Improvements in OM prevention and management are needed.