The journal Nature recognizes three main layers of skin: the epidermis, dermis and subcutaneous layer. Each layer is made up of different types of cells that perform a different function. Squamous cells are located just under the epidermal layer, and the associated carcinoma is a type of cancer that can occur in squamous cells around the body.
Solar Radiation
Every day, the sun beats down rays of potential dangerous ultraviolet radiation. This radiation is responsible for painful sunburns, but over time it can also lead to more dangerous conditions such as squamous cell carcinoma. Ultraviolet rays cause damage to the deoxyribonucleic acid in the squamous cells on the skin--which, if unrepaired, may cause uncontrolled cell growth. The odds of experiencing squamous cell carcinoma in correlation with sun or other ultraviolet light exposure increases due to skin type, family history, immune function and age, notes the American Academy of Dermatology.
Artificial Solar Radiation
Although many people believe use of a tanning salon or other indoor tanning booths is safe, the risks of skin cancer are often equivalent to receiving ultraviolet radiation from the sun. The United States Food and Drug Administration indicates there is an association between indoor tanning and increased risk for squamous cell carcinoma, and other types of skin cancers. The damage from artificial solar radiation lamps is similar because the types of radiation used--from the UV-B and UV-A spectrum--is similar to what is emitted from the sun.
Arsenic Poisoning
Arsenic poisoning over long periods can result in squamous cell carcinoma. Though different from solar and artificial radiation in source type, the presence of arsenic causes similar changes in the deoxyribonucleic acid in squamous cells, which over time can lead to a skin cancer. The Agency for Toxic Substances and Disease Registry notes that distinguishing between squamous cell carcinomas due to solar radiation and those related to arsenic can be difficult. One way to delineate is the location of the carcinoma. In solar radiation-based squamous cell carcinomas, the damage is often located in areas of the skin directly open to sun exposure. The arsenic-based damage is often on palms, the soles of feet, and other areas that may not typically be exposed to the sun.
Immunosuppressive Drugs
The immune system can aid in reducing the risk of cancer formation in the body. While recognizing cancer cells as foreign, the immune system attacks these cells before they can grow and become unmanageable. Immunosuppressive drugs, often taken after an organ transplant to reduce the likelihood of organ rejection, reduce the immune function and can put the patient at greater risk for squamous cell carcinoma development.
References
- Nature: The Structure of Human Skin
- American Academy of Dermatology: Squamous Cell Carcinoma
- United States Food and Drug Administration: Indoor Tanning: The Risks of Ultraviolet Rays
- Agency for Toxic Substances and Disease Registry: Arsenic Toxicity-What are the Physiologic Effects of Arsenic Exposure?
