The American Cancer Society says about 40% of people will develop a form of cancer at some point in their lifetime.

Lung cancer is expected to account for 20% of cancer deaths this year, according to the National Cancer Institute.

Despite that statistic, screening rates are extremely low.

"Less than 10% of those people who are eligible under the guidelines have come for screening in the U.S.” Claudia Henschke said.

Yearly screening, with a low-dose CT scan, is recommended for people who are at least 50, smoke or used to smoke, and have a 20 pack-year history of smoking. Doctors say this is a crucial step in catching it early.

“There are no symptoms of early lung cancer because there are no pain fibers in the lung,” Henschke said.

Colorectal cancer is the second-deadliest cancer. For people of average risk, screening is recommended to begin at age 45.

"It is something that is potentially preventable, and it's one of the only cancers that we can say that,” Dr. Brooke Glessing, a gastroenterologist at UH Cleveland Medical Center, said.

A majority of cases start from a non-cancerous polyp. Doctors can spot these during a colonoscopy.

Doctors say getting screened could make all the difference in the treatment, and the outcome.

“We can save your life,” Henschke said.

In April, the United States Preventative Services Task Force released new guidelines for breast cancer screenings. It now recommends mammograms every other year, starting at age 40. But the American Cancer Society recommends screening every year starting at age 45, with an option to start at age 40.

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