Comorbidity and diagnostic delay in cancer of the larynx, tongue and pharynx.

Comorbidity and diagnostic delay are independent prognostic factors in head and neck cancer, most notably in laryngeal cancer. We investigated their inter-relationship and their relative significance in survival of three different head and neck cancers. A population-based retrospective cohort of 221 patients with cancer of oral tongue, pharynx or larynx diagnosed between 1986 and 1996. Diagnostic delays and data on the onset of symptoms from real-time primary care charts. Comorbidity classified according to Charlson comorbidity index. Survival analyses were performed using Cox multivariate model. Significant association was found between increased comorbidity score and long professional delay in laryngeal cancer. In tongue cancer, longer patient delay and increased comorbidity were associated. In laryngeal cancer, high comorbidity (adjusted hazard ratio HR 5.6), professional delay of 6 months (HR 3.3) and advanced stage (HR 3.8) all were independent determinants of survival. In laryngeal cancer, comorbid illnesses are associated with professional diagnostic delay. However, despite their inter-correlation both comorbidity and professional delay are significant and independent prognostic factors.