Oral Health and Survival in Head and Neck Cancer

Poor oral health influences survival of patients with head and neck cancer: a joint analysis of the International Head and Neck Cancer Epidemiology Consortium

Head and neck squamous cell carcinoma is the sixth most common malignancy worldwide, with 878,348 cases of newly diagnosed patients in 2020. Although survival has improved in recent decades, head and neck squamous cell carcinoma remains one of the deadliest malignancies worldwide, with 444,347 deaths reported in 2020. Variation in the global incidence of head and neck squamous cell carcinoma reflects differences in the distribution of known risk factors, including smoking and exposure to tobacco, alcohol, human papillomavirus (HPV), and low socioeconomic status. Importantly, these risk factors have also been associated with differences in survival of patients with head and neck squamous cell carcinoma.

Poor oral health has been reported to be an independent risk factor for head and neck squamous cell carcinoma. Specifically, measures of poor oral health, including tooth loss, periodontal disease, infrequent tooth brushing, and lack of dental visits, have been associated with weak to moderate increases in the risk of SCC. scaly head and neck. Although the mechanisms underlying these associations remain unclear, chronic trauma, oral inflammation, and alterations in the oral microbiome have been proposed.

For example, oxidative stress is found in periodontal inflammation and epithelial mutagenesis and could link oral inflammation to cancer initiation and progression. Furthermore, Fusobacterium species known to be upregulated in oral squamous cell carcinoma were recently reported to induce upregulation of the programmed cell death ligand 1 and extracellular signal-regulated kinase 1 (ERK1) pathway that sends signals to the MYC proto-oncogene in head and neck squamous cell carcinoma and therefore potentially affecting tumor biology and treatment responses

Background

Poor oral health has been identified as a prognostic factor potentially affecting the survival of patients with head and neck squamous cell carcinoma. However, to date, evidence supporting this association comes from single cohort-based studies with small to modest sample sizes.

Methods

Pooled analysis of 2449 participants with head and neck squamous cell carcinoma from 4 studies of the International Head and Neck Cancer Epidemiology Consortium included data on periodontal disease, tooth brushing frequency, mouthwash use, number of natural teeth and visits to the dentist during the 10 years prior to diagnosis.

Multivariable generalized linear regression models were used and adjusted for age, sex, race, geographic region, tumor site, tumor node metastasis stage, treatment modality, education, and smoking status to estimate risk ratios (RR). of associations between oral health measures. and overall survival.

Results

Remaining natural teeth (10-19 teeth: RR = 0.81, 95% confidence interval [CI] = 0.69 to 0.95; ≥20 teeth: RR = 0.88, 95% CI = 0. 78 to 0.99) and frequent dental visits (>5 visits: RR = 0.77, 95% CI = 0.66 to 0.91) were associated with better overall survival.

The inverse association with natural teeth was most pronounced among patients with head and neck squamous cell carcinoma of the hypopharynx and/or larynx, and not otherwise specified.

The association with dental visits was most pronounced among patients with oropharyngeal head and neck squamous cell carcinoma. Patient-reported gingival bleeding, tooth brushing, and mouthwash use were not associated with overall survival.

Conclusions

Good oral health, defined by maintenance of natural dentition and frequent visits to the dentist, appears to be associated with better overall survival among patients with head and neck squamous cell carcinoma.

Comments

For patients with head and neck squamous cell carcinoma, good oral health is associated with better survival, according to a study published online September 19 in the Journal of the National Cancer Institute.

Jason Tasoulas, MD, of the Lineberger Comprehensive Cancer Center at the University of North Carolina at Chapel Hill, and colleagues conducted a pooled analysis of 2,449 participants with head and neck squamous cell carcinoma from four studies to examine poor oral health as prognostic factor. Data on periodontal disease, tooth brushing frequency, mouthwash use, number of natural teeth, and dental visits during the 10 years prior to diagnosis were included.

The researchers found that better overall survival was observed in association with remaining natural teeth (hazard ratio, 0.81 and 0.88 for 10 to 19 and ≥20 teeth, respectively) and frequent dental visits (hazard ratio, 0.77 for more than five visits). Patients with squamous cell carcinoma of the hypopharynx and/or larynx and not otherwise specified in the head and neck had the most pronounced inverse association with natural teeth. Patients with oropharyngeal head and neck squamous cell carcinoma had the most pronounced association with dental visits. No associations with survival were observed for patient-reported gingival bleeding, tooth brushing, and mouthwash use.

"These results emphasize the role of oral health maintenance not only in avoiding treatment-related adverse outcomes such as osteoradionecrosis, but also as a potentially independent prognostic parameter for patients with head and neck squamous cell carcinoma," the authors write.