Can Salivary Cotinine be Used as an Indicator of Tumour Characteristics & Outcomes: A Study of Current Trends in Head and Neck Malignancy

Study current clinical presentations of head and neck cancers; assess utility of salivary cotinine as a tobacco-related biomarker by correlating with stage, lesion site, and quality of life. Longitudinal study; 2 tertiary care centres. Inclusion criteria – Adults with head and neck malignancy. Exclusion criteria – Those unwilling/unable to comply with sampling criteria/follow-up at 1 month. Main Outcomes and Measures – Baseline cotinine levels compared with demographic data, stage, site, and quality of life parameters. No significant correlation found between salivary cotinine levels and cancer stage (p = 0.602), site (p = 0.397) or outcomes. However, 74.28% participants under-reported tobacco usage history, with continued use post-diagnosis in 51 of 70 patients. 76% incidence was in men, with highest presentation in stage III-IVa (n = 40). Most common site was buccal mucosa. Strong association noted between smokeless tobacco use, female gender and oral cavity primary (p = 0.046). Quality of life showed poorer data amongst women at 1 month in all functionality scales but only in social functioning scales at 3-months. Advanced age showed heightened perception of malignancy-specific symptoms at 1 month (95%CI: 0.03 to 0.44, p = 0.042). While salivary cotinine testing showed no significant relation with studied parameters, the study revealed important behavioural trends in tobacco use, revealing insights for better management of head and neck cancer patients.