Oral squamous cell carcinoma (OSCC) tumors from heavy alcohol consumers are associated with higher levels of TLR9 and a particular immunophenotype: Impact on patient survival

Abstract

Head and neck cancer was identified as the seventh most common cancer worldwide in 2018, with 890,000 new cases and 450,000 deaths being reported. Oral squamous cell carcinoma (OSCC) is the most prevalent subgroup of head and neck cancer and includes the lips, the tongue, the gums, the buccal mucosa, the floor of the mouth, the hard palate, and the alveolar ridge. It represents a major cause of morbidity and mortality worldwide, especially in Southern Asia and the Pacific islands (2). It arises as a consequence of multifactorial risk factors that include tobacco and alcohol, chronic inflammation, ultraviolet radiation (for lip cancer), human papilloma virus (HPV) or Candida infections, immunosuppression, genetic predisposition, and diet. However, tobacco smoking and alcohol consumption are considered as the main causal factors (3, 4). OSCC is still a leading cause of cancer death among men in many places and despite several advancements in therapeutic approaches, the 5-year survival rate is around 50% (1).