Lip and oral cavity cancer is a disease in which cancer cells form in the lips or mouth. The oral cavity includes the lips, hard palate (the bony front portion of the roof of the mouth), soft palate (the muscular back portion of the roof of the mouth), front two-thirds of the tongue, the gums, the inner lining of the lips and cheek (buccal mucosa), and the floor of the mouth under the tongue.
Most cancers start in the thin, flat squamous cells that line the lips and oral cavity. These squamous cell cancers usually develop in areas of leukoplakia (white patches of cells that do not rub off) and may spread into deeper tissues as the cancer grows. Known risk factors for developing cancers of the oral cavity are tobacco, heavy alcohol use and exposure to natural or artificial sunlight.1,2,3
Early signs of lip and oral cavity cancer are typically a sore or lump on the lips or in the mouth that does not heal. A white or red patch on the gums, tongue, or lining of the mouth is called leukoplakia, erythroplakia, or mixed erythroleukoplakia.4,5 These precancerous lesions should be brought to the attention of a doctor when identified, as should any unresolved sore throat or feeling that something is caught in the throat. Lip and oral cavity cancers may not have any symptoms and they are sometimes detected during a regular dental exam.
It is highly recommended that patients be carefully evaluated in medical centers that treat many patients with cancers of the head and neck. Patients with salivary gland cancer require a multidisciplinary team approach that is often only available at specialty medical centers. A multidisciplinary team may be comprised of a head and neck surgeon, a radiation oncologist, a medical oncologist, a pathologist, a dentist, and social services personnel. Evaluation by an experienced team is essential for determining optimal treatment.
Diagnosis and Staging
Diagnosis of cancer is confirmed by a biopsy and staging is the process of identifying how extensive the cancer is. Accurately identifying the stage of a cancer helps determine what treatments will be most effective. Staging is particularly important for determining whether a cancer has spread from its original site to other parts of the body.
Cancers are staged according to their size, lymph node involvement and presence of metastases.4,5 Magnetic resonance imaging (MRI) offers advantages over computed tomographic (CT) scanning in the detection of head and neck cancer and is preferred for evaluation of suspected neoplasms of the salivary glands.6
A diagnosis of a lip or oral cavity cancer usually involves several tests to help determine the size and extent of spread from its site of origin or stage. In addition to blood tests other tests may include;
- Endoscopy. An endoscope is a lighted tube, which is used to examine the throat, larynx, and upper esophagus. Endoscopy is performed to obtain a biopsy, determine the local extent of the cancer, and look for additional cancers
- Biopsy involves the removal of a small sample of the suspected cancer. The samples are then examined under a microscope to determine if cancer is present.
- Imaging Tests: Chest x-ray, CT scans, MRI scans, ultrasound, and positron emission tomography (PET) scans are often valuable for detecting the extent to which the cancer has spread to the lymph nodes and to further identify the extent of cancer at the primary location.
Early Stage Cancer
Stage I, II, and some stage III cancers are referred to as early stage. At these stages, the cancer is small, localized and can typically be treated with surgery or radiation therapy.
Stage I The cancer is no more than 2 centimeters (about 1 inch) and has not spread to lymph nodes in the area.
Stage II The cancer is more than 2 centimeters, but less than 4 centimeters (less than 2 inches) and has not spread to lymph nodes in the area.
Stage III The cancer is considered “early” if it is small and the single involved node can be removed or irradiated with high probability of cure. Stage III cancers that are more extensive than this are considered locally advanced.
Locally Advanced Cancer
Some stage III and all stage IV cancers are referred to as locally advanced. These are large and/or have spread to regional lymph nodes.
Stage III The cancer is more than 4 centimeters, or it is any size with spread to only one lymph node on the same side of the neck as the primary cancer. The lymph node containing the cancer can measure no more than 3 centimeters (just over 1 inch).
Stage IV The cancer has spread to tissues around the lip and mouth. The lymph nodes may or may not contain cancer or the cancer is any size and has spread to more than one lymph node on the same side of the neck as the cancer, to lymph nodes on one or both sides of the neck or to any lymph node that measures more than 6 centimeters (over 2 inches).
Metastatic Cancer has spread to distant sites.
Recurrent Cancer has failed to respond completely to primary treatment or has recurred after a complete response.
- Blot WJ, McLaughlin JK, Winn DM, et al.: Smoking and drinking in relation to oral and pharyngeal cancer. Cancer Res 48 (11): 3282-7, 1988..
- Neville BW, Day TA: Oral cancer and precancerous lesions. CA Cancer J Clin 52 (4): 195-215, 2002 Jul-Aug.
- Altieri A, Bosetti C, Gallus S, et al.: Wine, beer and spirits and risk of oral and pharyngeal cancer: a case-control study from Italy and Switzerland. Oral Oncol 40 (9): 904-9, 2004.
- Scheifele C, Reichart PA, Dietrich T: Low prevalence of oral leukoplakia in a representative sample of the US population. Oral Oncol 39 (6): 619-25, 2003.
- Shafer WG, Waldron CA: Erythroplakia of the oral cavity. Cancer 36 (3): 1021-8, 1975.
- Consensus conference. Magnetic resonance imaging. JAMA 259 (14): 2132-8, 1988. [PUBMED Abstract]