4D CT Could Spare Normal Lung Function in Lung Cancer Patients

A collaborative study, initiated by researchers at the University of Colorado Cancer Center, is evaluating an imaging method that can help protect normal, healthy lung tissue during radiotherapy treatment in lung cancer patients.

Using advanced image analysis techniques, the scientists plan to use results from 4D CT scans to map areas of the lung that have retained normal function without the need for additional testing. According to investigator Yevgeniy Vinogradskiy, PhD, lead investigator and assistant professor in the Department of Radiation Oncology at the CU School of Medicine, “We used to treat the lungs as a homogenous organ, as if all areas were equally important. Now we know that's not true - there's regionally variant function. The idea of this clinical trial is to spare functional portions of the lung during radiation by using this new imaging modality to display lung function.”

The complication arises from the fact that lung tumors move with every single breath that patients make, which makes a static image clicked at a specific time a crude estimate of the tumor’s position. The 4D CT, on the other hand, clicks a series of images shot over time to capture images of the lung and the tumor at different phases of the patient’s breathing cycle. Using the “lung function” information, which is information on the functional lung tissue around the tumor, physicians can carefully target the radiation so the normal tissue is spared during the process. The ultimate objective is to improve the patient’s quality of life.

The most important advantage, according to Vinogradskiy, is that there’s no additional testing required. The researchers will use existing imaging data acquired as part of standard of care. The trial will enroll 70 patients and is expected to be completed in 3 years.