Lung cancer is the leading cancer killer in the US, in both men and women.

CT-scans have been shown to detect lung cancer early and some hope it will decrease the number of deaths.

Other doctors say there are still too many questions and worry the scans do more harm than good.

Anne Morrison wanted to be sure.

She smoked for 30-years and was at high risk for lung cancer.

She signed up for a study in which she received a CT-scan.

It found a tumor in its early stages; one a standard x-ray would have missed.

Anne had the tumor removed and five and a half years later, she is cancer-free.

She is a success story that has many researchers excited.

Dr. Ralph Aye of the Swedish Medical Center said, "This is probably the biggest breakthrough we've had in lung cancer treatment in 50 years."

A recent study found annual CT-scans can detect lung cancer at its earliest stages in 85% of patients.

When the tumor is removed within a month, the ten year survival rate is 92%.

Traditionally it is 15%.