Survival rates for patients with lung cancer increase dramatically the earlier the disease is diagnosed, underscoring the need for effective biomarkers that can be used for detection. Now, researchers have found a protein that circulates in the blood that appears to be more accurate at detecting non-small cell lung cancer (NSCLC) than currently available methods used for screening. The findings were published in the journal Oncotarget.
The researchers searched for new biomarkers among cancer testis antigens (CTAs), since they are often found in tumor cells that circulate in the blood. After analyzing 116 different CTAs, they identified the protein AKAP4 as a potential biomarker that could effectively distinguish between patients with and without NSCLC.
The researchers then tested AKAP4 as a biomarker in a pilot cohort that contained 264 blood samples from patients with NSCLC and 135 control samples. Of the 264 NSCLC samples, 136 samples were from patients who received a stage I diagnosis. The researchers analyzed the effectiveness of the biomarker by looking at the area under the curve (AUC), a method that calculates the ability of the test to distinguish those with disease from those without it. An AUC value of 1 means that the test perfectly distinguishes between the patients who have and don't have a particular disease. When the researchers compared all 264 of the NSCLC samples with the 135 control samples, the AUC was 0.9714. When the researchers looked at only the 136 samples with known stage I disease, the AUC was 0.9795. While the researchers noted that the presence of AKAP4 increased with the stage of the disease, AKAP4 was still detectable in the samples with early stage disease.
With the positive results of this study, the researchers will conduct a larger study with a goal of analyzing at least 800 samples. Multiple hospitals have agreed to provide blood samples for analysis for the next study.
If the accuracy of the biomarker can be confirmed in the larger trial, it could lead to the development of a simple blood test that could be used for annual screening. The authors of the study believe that this blood test would be easier to use, more accurate and less invasive than low-dose computed tomography (LDCT) scans, the method for lung cancer screening currently recommended by the U.S. Preventive Services Task Force (USPSTF). Because of its accuracy, it could also better distinguish between benign lung tumors that do not pose a threat and malignant tumors that have the potential to grow and spread.
Based on material originally posted by The Wistar Institute.