The most common form of oral cancer is squamous cell carcinoma. It is most
commonly found on the lips, especially the lower lip. Inside the mouth, the posterior
lateral border of the tongue is the most common site for squamous cell carcinoma,
followed by the floor of the mouth. Oral cancer (figures 2-7 and 2-8) may appear as
leukoplakia (white plaque), erythroplakia (velvet-red plaque), or an ulceration. The red
patches (plaques) have a much higher potential of becoming malignant than do the
white plaques. Oral cancer is painless during the initial phase of development. It is
generally found in older individuals, occurring with greater frequency in males.
Metastatic potential varies with location. Cancer of the lip tends to metastasize later in
development, while cancer of the tongue tends to metastasize early. Tobacco is
regarded as the most important contributing factor for developing oral cancer. With the
use of smokeless tobacco, there is a significantly higher risk of developing oral cancer.
Since alcohol consumption also appears to add to the risk of oral cancer development,
lifestyle habits that mix smoking and drinking impose even greater risks for developing
The lower lip is a common site of oral cancer. Lesions are often present for
an extended time before being evaluated. Often, a small chronic scab may
be the only abnormality. Most affected lips show evidence of continuous
solar and ultraviolet light damage to the tissues.
Figure 2-7. Oral cancer, lower lip.