Low-dose CT Scan and Lung Cancer Diagnosis

In lung cancer, the prognosis is poor. Chest X-rays have long been used by doctors to diagnose lung cancer in people who have symptoms of the disease. But in 15 to 30 percent of the cases the disease has already spread beyond the lungs by the time lung cancer is diagnosed. 85 percent of lung cancer patients die within five years and what is unfortunate is that the tumor can grow for a long time before even being detected.

Trond Mogens Aaløkken at the Department of Radiology and Nuclear Medicine, Oslo University Hospital in cooperation with a group of physicists at the Intervention Centre has made a comparison of the proportion of patients who obtain a correct diagnosis with x-ray images and how many patients might have obtained a correct diagnosis with computer tomography (CT). In nowadays the low-dose CT scanners have become far more effective with the same low radiation dose as a regular x-ray image.

The results of their study were remarkable. By studying the x-ray images radiologists found the correct answer in only 18 percent of the cases. While with ultra low-dose CT the radiologists made a correct diagnosis in 89 percent of the cases.

CT can pick up much smaller tumors than can chest X-rays. The newer technology has been proposed as a screening tool to find early signs of lung cancer before it has spread in hopes of improving life expectancy. It is believed that the smaller the tumor when found, the higher the odds of long-term survival.