New research on lung cancer revealed that adding genetic information to previous or current smokers’ clinical risk profile leads to a reclassification of the risk of developing lung cancer in one fourth of the patients. The study entitled “Low-Dose Computer Tomography (CT) Lung Cancer Screening in the Community: A Prospective Cohort Study (REACT) Incorporating a Gene-Based Lung Cancer Risk Test” was led by Robert Young from the University of Auckland, New Zealand.
The research team performed a community-based study (REACT) by screening 157 individuals that undertook approved gene-based risk testing for lung cancer. The subjects were assigned to one of 3 risk categories—very high, high and moderate—by linking their genetic results with age, familiar history of lung cancer and chronic obstructive pulmonary disease. Preliminary data suggested that the individuals allocated in the highest risk category of lung cancer by genetic and clinical risk information adhered significantly to follow-up computed tomography (CT) scans during screening.
Dr. Young and other research teams have shown that the genetic component consists on 20 single nucleotide polymorphisms (SNPs) that have been involved in the development of lung cancer. The presence of SNPs can confer an increased or reduced risk of lung cancer depending on the number of SNPs, with 12 and 8 being associated to susceptibility or protection, respectively. According to genetic information, the researchers reclassified 28% of the individuals, among which 22% and 6% were re-distributed to higher and lower risk categories.
This is the first study to show the impact of gene-based risk evaluation and screening adherence. The findings of the study reinforce the results obtained by the National Lung Screening Trial that recruited more than 53,000 current or former heavy smokers with ages between 55 and 74 years old. The individuals included in the CT screening group had a 20% lower risk of dying from lung cancer if they performed CT scan of the lungs when compared to annual chest x-rays.
“Outside clinical trials, adherence to screening is typically 50 to 60 percent,” said Dr. Young in a news release. Dr. Young added that this study showed risk evaluation using personal genetic information is not only of major importance for the individuals but also seems to improve their compliance in performing routine screening. “Not only does adding personalized genetic data contribute to a better assessment of lung cancer risk, has it appeared to improve screening adherence,” Dr. Young concluded.