Health A-Z

Medical Content Created by the Faculty of the
Harvard Medical School

Head and Neck Cancer

What Is It?

Head and neck cancer begins with the abnormal growth of cells. These cancerous cells multiply out of control, eventually forming a tumor. As the tumor grows, it can form a lump, a sore, or an abnormal superficial patch of white or discolored tissue. Without treatment, the tumor can invade and destroy nearby bones and soft tissues. Eventually, it can spread (metastasize) to lymph nodes in the neck and to organs in other parts of the body. In many cases, head and neck cancers are triggered by carcinogens, substances that cause cancer. Common carcinogens include chemicals found in tobacco smoke, smokeless (chewing) tobacco and snuff. Chronic or heavy alcohol use also contributes to head and neck cancer. The disease is especially prevalent in those who both smoke and drink alcohol. In addition to the classifications listed below, head and neck cancers include those of the larynx (the voice box); the tongue; both the soft and hard palates; and tumors of the salivary glands, including the parotid gland.

Head and neck cancers are divided into according to where they are found:

• Upper aerodigestive tract — This includes the lips, mouth, throat and voice box (larynx). Of all head and neck cancers, those involving the upper aerodigestive tract are the most common. Almost all cancers in this part of the head are squamous cell carcinomas, which arise from a type of epithelial cell that makes up the structures of the head and neck area. Squamous carcinomas can also occur on the skin in the head and neck area, but a head and neck cancer that is of the squamous variety is not considered a skin cancer. These cancers are more common in people older than 45. Men are affected two to four times more often than women. More than 90% of cases are related to tobacco use. Alcohol increases the risk of cancers in this area of the body, especially when use is heavy and constant.

• Salivary glands — Salivary gland cancer is rare. There are several types of salivary gland cancer that vary in aggressiveness. Exposure to radiation increases the risk of this type of cancer, and smoking may play some role in certain types of salivary gland cancer. It has also been thought that people who have had chronic salivary gland stones and inflammation of the glands may be more prone to this disease.

• Nasopharynx — The nasopharynx is the upper portion of the back of the throat, where the throat meets the back of the nasal cavity. Unlike other head and neck cancers, this one is not associated with tobacco or alcohol use. This area is generally more sensitive to chemotherapy and radiation than other head and neck cancers. In the United States, nasopharyngeal cancer has not been associated with any particular cause. But in parts of northern Africa, Asia and the Arctic region, where this cancer is more common, it has been related to the following: infection with the Epstein-Barr virus (EBV), the cause of infectious mononucleosis; eating Cantonese salted fish; high exposure to dusts and smoke; and eating a lot of fermented foods.

• Sinuses and nasal cavity — Seventy-four percent to 79% of cancers found in the sinuses (behind the bones of the forehead and cheeks and inside the nose) are squamous cell carcinomas. Rarely, adenocarcinomas, melanomas and lymphomas also occur in this area. In many cases, these cancers grow fairly large before they are diagnosed. This is because the sinuses and nasal cavity have enough room for tumors to grow before they block the sinuses or nasal passages or cause other symptoms.