Causes of Basal Cell Carcinoma

Chronic sun exposure is one of the primary causes of basal cell carcinoma. Repeated exposure to ultraviolet light – including UV rays from commercial tanning beds – can cause genetic mutations in a person’s skin cells. In the case of basal cell carcinoma, these mutations occur in the basal cells, which are responsible for producing new skin cells as old cells are shed away.

The exact DNA mutations that lead to basal cell carcinoma are still being studied. However, researchers generally understand that:

  • When these DNA mutations occur, they program the basal cells to multiply at a faster rate than normal. And, while healthy cells ordinarily die when it’s time for them to be replaced by new ones, DNA mutations can also prevent the basal cells from dying when they should.
  • Over time, the rapidly multiplying basal cells can start to accumulate and form a tumor. 
  • With basal cell carcinoma, the abnormal cells typically do not spread throughout the rest of the body, but the tumor can eventually get larger and grow deeper through multiple layers of skin.

Although most basal cell carcinomas can be attributed to this process, some are not caused by UV exposure. Other factors, such as a history of exposure to other carcinogenic substances, or having a condition that compromises the immune system, may also cause basal cell carcinoma to develop.

Moffitt Cancer Center’s research teams are continually working to better understand the causes of basal cell carcinoma. Not only are we investigating the genetic mechanisms behind its development, but also the most effective treatments to provide patients with the best possible outcomes and improved qualify of life. To learn more about our approach to treating basal cell carcinoma, call 1-888-663-3488 or complete a new patient registration form online; no referral is required to meet with our expert oncologists.