TAMPA, Fla. – Early detection is key when it comes to lung cancer, but a problem physicians face is identifying which patients with small lung nodules are at a greater risk of eventually developing the disease. Moffitt Cancer Center researchers have made significant progress towards a solution. They have developed a new model based on features of computerized tomography (CT) patient scans to distinguish those patients at a greater risk of lung cancer. Their findings were published online ahead of print in the journal Radiology.
A recent study called the National Lung Screening Trial (NLST) found that low-dose helical CT screening is associated with a reduced risk of death due to lung cancer by 20 percent when compared to standard chest X-rays. Low-dose CT is now the recommended test to screen for lung cancer; however, it also detects abnormalities that are not cancer such as small pulmonary nodules (SPNs). SPNs are occasionally cancerous, but more commonly they are caused by infections or inflammation and are typically managed by routine surveillance and imaging.
In order to reduce the rate of false positive CT scans, SPNs of less than 4 millimeters were considered a negative result during the NLST. Unfortunately, a follow-up analysis found that patients who initially had a negative CT scan with SPNs less than 4 millimeters and later developed lung cancer had a poorer overall prognosis. The observations suggest that SPNs in these patients may be more aggressive.
Moffitt researchers believe the use of radiomic biomarkers could be used to determine which patients with a negative CT screening test and small SPNs are at a greater risk of developing lung cancer. Radiomics is a relatively new scientific area that quantitates features of images from CT, MRI, or PET scans to determine patients’ prognoses, outcomes, or to guide treatment.
“Lung cancer screening participants with SPNs may represent a more vulnerable population because of the possibility of developing a highly aggressive tumor. Image-based biomarkers could assist in identifying high-risk participants and biologically aggressive nodules,” explained Matthew Schabath, Ph.D., corresponding author and associate member of the Cancer Epidemiology Program at Moffitt.
The Moffitt team compared the image features of 73 participants from the NLST trial who had an initial negative CT screen with small SPNs and eventually developed lung cancer with 157 control participants with small SPNs who had three consecutive negative CT screens and did not develop lung cancer. They used the results to develop a model that includes five different radiologic features that could be used to differentiate patients with SPNs who have an increased risk of developing lung cancer.
“The features we identified can be easily scored in the clinical setting to determine which patients with small pulmonary nodules are at an increased risk for lung cancer,” said Schabath.
It is anticipated that this new radiologic model could significantly increase the sensitivity of detecting those patients at a high-risk of developing lung cancer and reduce the false-positive rate of lung cancer detection. Those patients who are at a higher risk could be followed more closely and treated earlier to prevent lung cancer progression and death. While these results are promising, additional follow-up studies are needed to confirm the model.
Funding support for the study came from the National Cancer Institute (U01-CA143062, U01-CA200464, U01-CA186145, P30-CA76292) and Florida’s James and Esther King Biomedical Research Program (2KT01).
About Moffitt Cancer Center Moffitt is dedicated to one lifesaving mission: to contribute to the prevention and cure of cancer. The Tampa-based facility is one of only 49 National Cancer Institute-designated Comprehensive Cancer Centers, a distinction that recognizes Moffitt’s excellence in research, clinical trials, prevention and cancer control. Moffitt is listed as one of the top 10 cancer hospitals in the nation and has been listed in U.S. News & World Report as one of the “Best Hospitals” for cancer care since 1999. Moffitt devotes more than 2 million square feet to research and patient care. Moffitt’s expert nursing staff is recognized by the American Nurses Credentialing Center with Magnet® status, its highest distinction. With more than 5,600 team members, Moffitt has an economic impact in the state of $2.1 billion. For more information, call 1-888-MOFFITT (1-888-663-3488), visit MOFFITT.org, and follow the momentum on Facebook, Twitter and YouTube.