Significance
An estimated 35,310 new cases of oral cancer are expected to be diagnosed in
the United States in 2008, and an estimated 7,590 people will die of the
disease.[1] This form of cancer accounts for about 3% of cancers in men [1] and 2%
of cancers in women.[2] Oral cancer occurs more frequently in blacks than in whites.[3]
More than 90% of oral cancers occur in patients older than 45 years. The
incidence increases steadily until age 65 years, when the rate levels off. Over
the last 22 years, there have been slight decreases in incidence and mortality
rates.
Reports have noted a substantial increase in the incidence of oral cancer (particularly of the tongue) among adults younger than 40 years in the United States between 1973 and 1997.[4]
The primary risk factors for oral cancer in American men and women are tobacco
(including smokeless tobacco) and alcohol use. Infection with human papillomavirus 16 has
been associated with an excess risk of developing squamous cell carcinoma of
the oropharynx.[5]
No population-based screening programs for oral cancers have been implemented in developed countries, although "opportunistic screening" has been advocated.[6,7] There are different methods of screening for oral cancers. Oral cancer occurs in a region of the body that is generally accessible to
physical examination by the patient, the dentist, and the physician, and visual examination is the most common method used to detect visible lesions. Other methods have been used to augment clinical detection of oral lesions and include toluidine blue, brush biopsy, and fluorescence staining.
Screening
examination can be made more efficient by inspecting the high-risk sites where
90% of all oral squamous cell cancers arise: the floor of the mouth, the
ventrolateral aspect of the tongue, and the soft palate complex.[8] An inspection of the oral cavity is often part of a physical examination in a dentist's or physician's office. It has
been pointed out that high-risk individuals visit their medical doctors more
frequently than they visit their dentists. Although physicians are more likely to provide risk-factor counseling (such as tobacco cessation), they are less likely than dentists to perform an oral cancer examination.[9] Overall, only a fraction (~20%) of Americans receive an oral cancer examination. Black patients, Hispanic patients, and those who have a lower level of education are less likely to have such an examination, perhaps because they lack access to medical care.[9] An
oral examination often includes looking for leukoplakia and erythroplastic
lesions, which can progress to cancer.[10] One recent study has shown that direct fluorescence visualization (using a simple hand-held device) could identify subclinical high-risk fields with cancerous or precancerous changes in the oral mucosa.[11] However, this finding has not yet been tested in a screening setting. Recent data suggest that molecular
markers may be useful as markers of prognosis for these premalignant oral
lesions.[12]
Although it is possible to detect and cure early-stage oral cancers, most oral cancers
are moderately advanced (regional stage) at the time of diagnosis.
Unfortunately, this pattern has not changed over time.
References
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American Cancer Society.: Cancer Facts and Figures 2008. Atlanta, Ga: American Cancer Society, 2008. Also available online. 1 Last accessed October 1, 2008.
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American Cancer Society.: Cancer Facts and Figures 2004. Atlanta, Ga: American Cancer Society, 2004. Also available online. 2 Last accessed January 21, 2008.
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Ries LA, Kosary CL, Hankey BF, et al., eds.: SEER Cancer Statistics Review 1973-1995. Bethesda, Md: National Cancer Institute, 1998.
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Schantz SP, Yu GP: Head and neck cancer incidence trends in young Americans, 1973-1997, with a special analysis for tongue cancer. Arch Otolaryngol Head Neck Surg 128 (3): 268-74, 2002.
[PUBMED Abstract]
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Mork J, Lie AK, Glattre E, et al.: Human papillomavirus infection as a risk factor for squamous-cell carcinoma of the head and neck. N Engl J Med 344 (15): 1125-31, 2001.
[PUBMED Abstract]
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Opportunistic oral cancer screening: a management strategy for dental practice. BDA Occasional Paper 6: 1-36, 2000 Also available online. 3 Last accessed January 21, 2008.
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Update January 1992: the American Cancer Society guidelines for the cancer-related checkup. CA Cancer J Clin 42 (1): 44-5, 1992 Jan-Feb.
[PUBMED Abstract]
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Mashberg A, Barsa P: Screening for oral and oropharyngeal squamous carcinomas. CA Cancer J Clin 34 (5): 262-8, 1984 Sep-Oct.
[PUBMED Abstract]
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Kerr AR, Changrani JG, Gany FM, et al.: An academic dental center grapples with oral cancer disparities: current collaboration and future opportunities. J Dent Educ 68 (5): 531-41, 2004.
[PUBMED Abstract]
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Chiodo GT, Eigner T, Rosenstein DI: Oral cancer detection. The importance of routine screening for prolongation of survival. Postgrad Med 80 (2): 231-6, 1986.
[PUBMED Abstract]
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Poh CF, Zhang L, Anderson DW, et al.: Fluorescence visualization detection of field alterations in tumor margins of oral cancer patients. Clin Cancer Res 12 (22): 6716-22, 2006.
[PUBMED Abstract]
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Poh CF, Zhang L, Lam WL, et al.: A high frequency of allelic loss in oral verrucous lesions may explain malignant risk. Lab Invest 81 (4): 629-34, 2001.
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