Throat cancer is the malignant growth of cells in the pharynx, larynx (voice box), or tonsils. The cancer itself is not contagious. You cannot catch throat cancer from another person through casual contact, kissing, or sharing food.
Why Cancer is Not Spread Through Contagion
Contagious diseases, such as the flu or strep throat, are caused by transmissible external pathogens like viruses, bacteria, or fungi that invade the body. Cancer, by contrast, is a disease of the body’s own cells, characterized by uncontrolled growth and division due to genetic mutations. These mutated cells originate within a person’s tissues and are not equipped to survive the journey or the immediate immune response of a new, healthy host. When a person’s immune system encounters foreign cells, such as those from another human, it immediately recognizes and destroys them.
The Role of Viruses as Cancer Triggers
Confusion about contagion often arises because certain viruses are strongly linked to the development of throat cancer. The most prominent example is Human Papillomavirus (HPV), particularly the high-risk type HPV-16, which is responsible for the majority of oropharyngeal cancers, specifically those in the tonsils and base of the tongue. This virus is highly contagious and is transmitted primarily through intimate skin-to-skin contact, including oral sex. The virus itself is passed from person to person, but the resulting cancer is not.
The HPV-16 virus causes malignant transformation by introducing two viral oncoproteins, E6 and E7, into the host cell. These oncoproteins interfere with the cell’s natural “brake pads”—the tumor suppressor proteins p53 and retinoblastoma protein (pRb). By inactivating these proteins, E6 and E7 allow the infected cell to bypass normal checkpoints, leading to uncontrolled proliferation and genomic instability years later. Another virus, the Epstein-Barr virus (EBV), which causes mononucleosis, has also been associated with an increased risk of nasopharyngeal cancer.
Primary Causes Beyond Infection
If a viral infection is not the cause, the risk for developing throat cancer is overwhelmingly linked to non-infectious, lifestyle, and environmental factors. Tobacco use, whether smoked or chewed, is the single largest risk factor, exposing the delicate throat lining to numerous carcinogens. Heavy alcohol consumption also significantly raises this risk, and the combination of both tobacco and alcohol has a synergistic, or greater than additive, effect.
For instance, studies show that combining heavy drinking and smoking can increase the risk for laryngeal cancer by as much as 177 times compared to abstaining from both. This is because alcohol acts as a solvent, making the throat tissues more permeable and allowing tobacco carcinogens to penetrate more deeply. Chronic acid reflux, specifically laryngopharyngeal reflux (LPR), is another risk factor, as the repeated exposure of the larynx and pharynx to stomach acid and digestive enzymes causes chronic inflammation and mucosal damage.