BAKERSFIELD, Calif. -- Two new studies show that non-melanoma skin cancer affects more individuals than all other cancers combined. One medical authority calls it an "epidemic."

Non-melanoma skin cancer is less aggressive than melanoma-type cancers, but it is far more common and is responsible for significant illness, costs and death.

Non-melanoma skin cancer was not typically reported to cancer registries in the past. So researchers looked back over the past 50 years, and along with new diagnoses, concluded that in 2007 13 million white, non-Hispanic Americans had had at least one non-melanoma skin cancer.

The study also found that one in five 70-year-olds have had non-melanoma skin cancer, many of them more than once.

The total number of procedures to treat skin cancer in the Medicare population increased from approximately 1.6 million procedures in 1992 to approximately 2 million procedures in 2006.

One researcher wrote that educating the public about sun protection has been " disappointing" in slowing the disease, and that more research is needed into treating and preventing non-melanoma skin cancer.