Avoiding exposure to the sun is very important. Spending less time in the sun will greatly lower a person's chances of developing basal cell cancer. When exposure to the sun can't be avoided, a person should use protective sunscreens. However, sometimes people spend more time in the sun when they are using sunscreen. It is important not to spend too much time in the sun whether the skin is protected or not.
If basal cell cancer is not treated, it will destroy the skin around it. It can destroy underlying tissue as well. Basal cell cancer generally only affects the tissue and structures around it. It doesn't usually spread through the blood to other areas of the body. As with any cancer, early detection is important.
There are no risks to others from those who have basal cell cancer. It cannot be spread from one person to another.