Oral Salivary Gland Cancer
Causes of Oral Salivary Gland Cancer
As with most cancers, doctors can’t tell you with certainty what causes oral salivary gland cancer. It’s a combination of genetic predisposition and factors in your environment.3Petersen PE, Oral cancer prevention and control – The approach of the World Health Organization. Oral Oncol. 2008.
While many cancers in the head and neck are caused by exposure to alcohol and tobacco, salivary gland cancers do not seem to be associated with these bad habits. In most cases of salivary gland cancer, there is no clear cause; however, one factor that probably does increase the risk of developing a salivary gland cancer is radiation. This may be in the form of therapeutic radiation or exposure to radiation in the environment. There are a few other causes listed below that might be related as well, but the medical community has not reached agreement about them.
- Radiation: Studies following survivors of the atomic bomb explosions in Hiroshima and Nagasaki have shown quite a significant increased risk for developing malignant salivary gland carcinomas after exposure to high levels of radiation. The risk is up to eleven times higher than in people not exposed to such a high level of radiation. There is also some evidence that patients treated with radiation for other tumors in the region of the head and neck are at an increased risk of developing malignant tumors in the salivary glands.
Recent studies have shown that patients who receive radioactive iodine (i.e., I-131) are also at increased risk of developing salivary gland cancers.4, Johansen C, Boice Jr JD, McLaughlin JK, Olsen JH. Cellular telephones and cancer—a nationwide cohort study in Denmark. Journal of the National Cancer Institute. 2001;93:203-7.5, Auvinen A, Hietanen M, Luukkonen R, Koskela RS. Brain tumors and salivary gland cancers among cellular telephone users. Epidemiology. 2002;13:356.6Atula T, Grenman R, Klemi P, et al. Human papillomavirus, Epstein-Barr virus, human herpes virus 8 and human cytomegalovirus involvement in salivary gland tumours. Oral Oncol. 1998;34:391-395.Dental X-rays may increase the risk of a malignant salivary gland tumor, as may exposure to ultraviolet radiation. Currently, there does not seem to be any support for microwaves or cellular telephones being associated with risks of cancer of the salivary glands.4, Johansen C, Boice Jr JD, McLaughlin JK, Olsen JH. Cellular telephones and cancer—a nationwide cohort study in Denmark. Journal of the National Cancer Institute. 2001;93:203-7.5Auvinen A, Hietanen M, Luukkonen R, Koskela RS. Brain tumors and salivary gland cancers among cellular telephone users. Epidemiology. 2002;13:356.
- Viruses: While a few viruses have been said to possibly increase the risk of salivary gland cancer, the evidence is not overwhelming. Viruses such as HIV-1, HPV types 16 and 18, polyomavirus and Epstein-Barr might be related.6, Atula T, Grenman R, Klemi P, et al. Human papillomavirus, Epstein-Barr virus, human herpes virus 8 and human cytomegalovirus involvement in salivary gland tumours. Oral Oncol. 1998;34:391-395.7Sun EC, Curtis R, Melbye M, et al. Salivary gland cancer in the United States. Cancer Epidemiol Biomarkers.1999;Prev 8:1095-1100.
- Workplace environment: Salivary gland cancer may be associated with substances found in some workplaces, including asbestos, rubber, nickel and various chemicals. Those who work in manufacturing, plumbing, hairdressing and the auto industry may be at increased risk.7, Sun EC, Curtis R, Melbye M, et al. Salivary gland cancer in the United States. Cancer Epidemiol Biomarkers.1999;Prev 8:1095-1100.8Horn-Ross PL, Ljung BM, Morrow M. Environmental factors and the risk of salivary gland cancer. Epidemiology. 1997:414-9.
- Hormones: There is ongoing research as to whether hormone receptors are present in certain salivary gland cancers and how they might relate to cancer (as in breast cancer). However, the information is conflicting, and researchers don’t have clear information on this yet.