Details of TALENT findings
The TALENT study recruited individuals aged 55-70 years at 17 medical centers between February 2015 and July 2019.
Participants were required to be never-smokers or to have a smoking history of less than 10 pack-years and to have quit the habit more than 15 years previously.
They also had to have one of the following risk factors:
- Family history of lung cancer in up to third-degree relatives, in which case younger patients could be recruited.
- Environmental (passive) tobacco smoking history.
- Chronic lung disease, namely, or .
- A cooking index ≥110, defined as 2/7 × the number of days of frying per week × the number of years cooking.
- Cooking without ventilation.
The participants underwent chest x-ray. If the x-ray proved negative, the team performed standard LDCT, examined blood and urine samples for lung cancer biomarkers, and administered standard questionnaires.
Participants who were found on LDCT to have solid or part-solid nodules greater than 6 mm in diameter or pure ground-glass nodules greater than 5 mm in diameter underwent biopsy or standard follow-up.
Individuals whose initial chest x-ray was positive underwent standard contrast-enhanced chest CT prior to biopsy or standard follow-up.
Of 13,207 individuals initially screened, 12,011 were enrolled. Of those, 73.8% were women. The mean age was 61.2 years, and 93.3% were never-smokers.
Among the participants, 46.4% had a first-degree family history of lung cancer; 3.0% had a second-degree family history; and 0.5% had a third-degree family history.
Environmental tobacco exposure was recorded in 83.2% of patients. Chronic lung disease was present in 9.8%; 36.7% had a cooking index ≥110; and 1.8 cooked without ventilation.
Dr. Yang said LDCT results were positive for 17.4% of patients, and 3.4% underwent invasive procedures.
Overall, lung cancer was detected in 313 participants (2.6%). Invasive lung cancer was detected in 255 (2.1%). Of those, 17.9% had multiple primary lung cancers.
Strikingly, 96.5% of the confirmed lung cancer cases were stage 0-I. The majority were stage IA, “which is higher than in other studies that have focused on heavy smokers,” Dr. Yang said. More than half of cases (58.5%) were invasive adenocarcinomas.
The prevalence of lung cancer was significantly higher among people who had a family history of the disease, at 3.2%, vs. 2.0% in those without, at a relative risk of 1.61 (P < .001).
The prevalence was higher still in individuals who had a first-degree family history of lung cancer, at 3.3%, giving a relative risk of 1.69 in comparison with those who did not have a family history (P < .001). The findings were nonsignificant for second- and third-degree relatives.
The relative risk increased even further when the first-degree relative who had a history of lung cancer was a sister, at 1.78 (P < .001), or a brother, at 2.00 (P < .001).
The relative risk was slightly lower if the patient’s relative was the mother, at 1.43 (P = .010), and was nonsignificant if the relative was the father (P = .077).
The risk for lung cancer also increased with an increase in the number of first-degree relatives with the disease, rising from 3.1% with one relative to 4.0% with two relatives, 6.7% with three relatives, and 9.1% with at least four relatives (P < .001). A similar pattern was seen for invasive lung cancer.
The other risk factors included in the study, such as environmental tobacco exposure, chronic lung disease, and cooking index, were not significantly associated with the prevalence of lung cancer.
No funding for the study has been disclosed. Dr. Yang has received honoraria from AstraZeneca, Boehringer Ingelheim, Pfizer, Merck, Eli Lilly, Roche, GlaxoSmithKline, and ONO Pharma and has served on the advisory board of OBI Pharma, CHO Pharma, and Lin BioScience. Dr. Pastorino has disclosed no relevant financial relationships.
A version of this article first appeared on Medscape.com.