Lip cancers

RELATED CONDITIONS: Other oral or skin cancers

DEFINITION: Lip cancers are tumors that form in the surface layer cells of the upper or, more comonly, the lower lip. Though lip cancers are generally similar to skin cancers, they are often grouped with oral cancers.

Risk factors: Smoking, especially smoking a pipe or cigar, and exposure to sunlight are the best-documented risk factors for lip cancers. According to some studies, 90 percent of people who have any type of oral cancer smoke.

The aging process itself is also a risk factor. As lip cells age and change, they are more susceptible to cancer cell generation. These factorssmoking, exposure to sunlight, and the aging processmay work in combination to increase risk. Alcohol consumption is a for developing other types of oral cancer (about 75 percent of patients with any type of oral cancer drink alcohol frequently) and may contribute to lip cancers.

Other risk factors include poor oral hygiene, a suppressed immune system (often due to organ transplant treatment), vitamin deficiency, or viral infections like strains 16 and 18 of the human papillomavirus (HPV),

Etiology and the disease process: Lip cancers almost always (about 90 percent of the time) originate in the flat skin cells (squamous cells) that form the outside covering layer of the lips. These cancers behave like skin cancers. The other 10 percent of lip cancers are basal cell carcinomas or melanomas.

This type of cancer begins with a sore, usually a bleeding sore that does not heal. If not treated, this cancer may move into other portions of the mouth, such as the tongue and the mucous membranes inside the lips. The next spread of the cancer may be into the lymph nodes, and the cancer may spread even farther into other areas of the body. Generally, cancers that begin in the upper lip are more aggressive than those that originate in the bottom lip and may be more likely to spread.

Incidence: About 90 percent of people who develop lip cancers are over the age of fifty-five, and as age increases, this type of cancer is even more likely. Men are more than twice as likely than women to get this cancer. Fair-skinned people are also more likely than those with darker skin to develop lip cancer. Around 40,000 cases of lip cancer are diagnosed annually in the United States.

Symptoms: Symptoms include lumps, sores, or white spots on the lips, particularly bleeding or open sores that do not heal in a reasonable time. Lumps or white spots may or may not be painful. Pain may also be felt in a lymph node near the lip area.

Screening and diagnosis: Dentists often perform a screening for lip and other oral cancers at a regular dental checkup by examining the lips and mouth for suspicious symptoms. X-rays may also help spot lip cancer.

Noncancerous sores, lumps, and white spots often occur on the lips, and lip cancer may resemble these conditions. Because of this, removing a small piece of tissue and examining it under a microscope for cancerous cellsis generally the preferred method of diagnosis.

Staging of lip cancer is broken into four parts based on how large the tumor or sore is and how far the cancer has spread.

• Stage I: The tumor is less than two centimeters (cm) and has not spread.
• Stage II: The tumor is more than two cm but less than five cm and has not spread.
• Stage III: The tumor is larger than four cm, or the tumor is any size, and the cancer has spread to a lymph node in the neck on the side where the cancer is located, with the lymph node being no more than three cm.
• Stage IV: The cancer has spread to the mouth or other areas around the lip (with or without lymph node involvement); it is any size and has spread to more than one lymph node on the same side of the neck, to lymph nodes on both sides of the neck, or to any lymph node that measures more than six cm; or it is any size and has spread to other parts of the body.

Treatment and therapy: Surgery is generally the first line of treatment for lip cancer, especially in Stages I and II. (using chemicals in the bloodstream to kill cancer cells) or radiation therapy (using high-energy rays to focus on and kill cancer cells) may also be necessary, depending on whether the cancer has spread. Chemotherapy or radiation therapy may also be used before surgery to shrink a tumor. In Stages III and IV, the lymph nodes affected by the cancer are also surgically removed.

Some other types of treatment may be possible depending on the size or extent of the cancer. These types of treatment may involve freezing or burning the cancerous cells on the lips or using chemicals in an acid, cream, solution, or ointment applied to the lips to kill the cancerous cells.

Surgical treatment of this type of cancer always considers the patient’s ability to eat and speak following tissue removal. If treatment of lip cancer involves surgical removal, reconstructive surgery may be needed. Even with reconstructive surgery, there may be significant changes in eating and speaking abilities, especially if muscle tissue is removed. Occupational or speech therapy may improve those functions.

Other treatment may involve counseling for issues dealing with scars or disfigurement from the surgery. Patients may need to work with a nutritionist to ensure proper nutrition and eating habits after surgery or during radiation therapy, when the lips and mouth may be sore, making eating difficult.

A promising treatment for lip cancer therapy is hyperthermia, a process that uses heat to kill cancer cells. In this type of therapy, a special machine heats the body for a certain amount of time. Cancer cells are often more sensitive to heat than healthy cells, so this treatment may kill the cancer while leaving healthy cells intact. This type of therapy may also be combined with other types of therapy, such as freezing or burning the cancer cells.

Prognosis, prevention, and outcomes: Early lip cancer identification and diagnosis improves prognosis. Quitting smoking is the most effective prevention for any type of oral cancer. Quitting pipe smoking is helpful for lip cancer in particular, as it is more closely associated with lip cancer. The heat of the pipe stem on the lips is thought to increase the likelihood of cancer developing. Other preventive measures include avoiding sun exposure, using lip balm or lipstick with a sun protection factor (SPF) rating of fifteen or more, limiting alcohol use, and increasing fruit and vegetable consumption.

Prognosis and outcomes are very good for patients when lip cancer is discovered early, especially in Stage I or II, and the cancer is squamous-cell based, with five-year survival rates of over 90 percent and ten-year survival rates over 95 percent. If the cancer is at Stage III or IV when discovered, survival rates fall to about 50 percent. Survival rates for those with lip cancers that are carcinoma-based are about 10 to 20 percent less than the squamous-based survival rates. The global mortality rate for lip and oral cancers is 2 out of 100,000 people.

Bibliography

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Cheng, Ming-Huei, et al. Resection and Reconstruction of Head & Neck Cancers. Springer, 2019.

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"Lip and Oral Cavity Cancer Treatment (Adult) (PDQ®)–Patient Version." National Cancer Institute, 14 Oct. 2021, www.cancer.gov/types/head-and-neck/patient/adult/lip-mouth-treatment-pdq. Accessed 20 June 2024.

"Lip Cancer." Cleveland Clinic, 21 Oct. 2021, my.clevelandclinic.org/health/diseases/21933-lip-cancer. Accessed 20 June 2024.