Lung cancer is the number one cause of cancer death worldwide, accounting for more than 1.3 million deaths a year. Since the disease is hard to detect in early and treatable stages, most cases are found only after the cancer has spread. Studies have shown CT scans can identify the disease in an early stage in individuals considered at high risk for lung cancer, but they also identify many noncancerous lesions in the process.
In a recent study, researchers used PET scans to confirm findings from CT scans in more than 1,000 heavy smokers considered at high risk for lung cancer. All had annual CT scans for up to five years. As with previous studies of CT scanning for lung cancer, nodules were identified in a significant percentage of the group -- 29 percent. Most were small, and the protocol called for lesions up to five millimeters to be followed up with using another scan in a year rather than further treatment. Only 9 percent of the participants underwent further investigation of suspicious lesions using a higher-resolution CT scan with or without PET scanning. In this group, 23 percent were found to have lung cancer. Doctors were able to completely remove the cancerous tumors in 95 percent of the cases.
However researchers say additional study is required to see if regular scanning for lung cancer can reduce mortality from the disease.