Patient-reported oral complaints during cancer treatment: Dietary consequences, supportive care, and self-management in a cross-sectional survey

Background Oral complaints are common during cancer treatment and may interfere with eating and perceived quality of life. However, patient-reported evidence addressing dental and gingival complaints, xerostomia, taste alterations, counselling, and self-management remains limited. Methods We conducted an anonymous cross-sectional survey among adults in Germany with current or previous oncological treatment using paper-based and online questionnaires (January-June 2025). Analyses were based on valid responses for each item and included descriptive statistics, Pearson’s chi-square tests, linear-by-linear association tests, 95% confidence intervals for selected key prevalence estimates, and exploratory multivariable logistic regression sensitivity analyses adjusted for age and gender. Results The survey included 222 patients. New, additional, or worsening dental and gingival complaints during cancer treatment were reported by 41.9% (83/198; 95% CI 35.3–48.9%) of respondents. Xerostomia was reported by 56.6% (120/212; 95% CI 49.9–63.1%) and taste alterations by 68.0% (138/203; 95% CI 61.3–74.0%). Self-reported reduced food intake attributed to dental or gingival complaints was reported by 27.9% (57/204; 95% CI 22.2–34.5%), while 25.0% (46/184; 95% CI 19.3–31.7%) reported perceived quality-of-life impairment attributed to these complaints. In exploratory sensitivity analyses adjusted for age and gender, new, additional, or worsening complaints remained associated with reduced food intake (adjusted OR 7.85, 95% CI 3.70-16.62) and perceived quality-of-life impairment (adjusted OR 15.25, 95% CI 5.81–40.06). Among participants with xerostomia, the proportion reporting reduced food intake increased from 5.1% among those with no xerostomia-related eating difficulty to 91.7% among those with severe difficulty ( p < 0.001). Overall, 43.1% (87/202; 95% CI 36.4–50.0%) reported receiving support or counselling regarding oral health. Conclusions In this recruited sample, oral complaints during cancer treatment were common and were associated with eating-related burden and perceived quality-of-life impairment. These exploratory associations persisted after limited adjustment for age and gender but do not establish causality. Fewer than half of respondents reported receiving oral-health counselling, although perceived helpfulness was high among recipients, suggesting a potential gap in the reach of such support. These findings support prospective evaluation of repeated, function-oriented oral-health assessment and appropriate dental or nutritional referral rather than demonstrating the effectiveness of these approaches.