Screening for lung cancer CHEST guideline and expert panel report

Key points

• Annual low-dose CT screening should be offered to asymptomatic people aged 55 to 77 with at least 30 pack-years who still smoke or quit within the past 15 years (strong recommendation, moderate-quality evidence).
• Annual screening is also suggested for people aged 50 to 80 with at least 20 pack-years who still smoke or quit within 15 years, and for others projected to have a high net benefit by validated risk or life-year calculators (weak, moderate).
• Screening should not be performed in people with life-limiting comorbidities that affect their ability to tolerate evaluation or treatment (strong, low).
• Programs should define a positive test by nodule size, using a threshold of 4 mm, 5 mm or 6 mm in diameter (weak, low).
• Current smokers in screening programs should receive evidence-based tobacco cessation treatment (strong, low).

Overview

This American College of Chest Physicians (CHEST) guideline updates the evidence on the benefit, harms and implementation of low-dose chest CT screening and gives 16 recommendations and consensus-based statements. It covers who should be screened, how programs should be run, how findings should be managed and how smoking cessation should be built in. The literature search covered September 2017 to June 2019 and included 233 source documents.

Who should be screened

Beyond the two age and pack-year groups above, screening is not recommended for people with fewer than 20 pack-years, those younger than 50 or older than 80, or those who quit more than 15 years ago, unless risk prediction or life-year gained calculators project a high net benefit (strong, moderate). Programs should identify symptoms that suggest lung cancer so that symptomatic patients receive diagnostic testing instead of entering screening, whether or not they meet eligibility criteria.

Running a high-quality program

Consensus statements advise counselling and shared decision-making visits before the scan, strategies to maximise adherence to annual screening, following ACR/STR protocols for low-dose CT and using a structured reporting system. Programs should also plan for non-nodule findings and collect data for quality improvement and reporting to the national registry.

Managing findings

Programs should take a comprehensive, multidisciplinary approach to nodule management, involving pulmonology, radiology, thoracic surgery and medical and radiation oncology, with algorithms for small solid, larger solid and subsolid nodules. They should also develop strategies to minimise overtreatment of potentially indolent lung cancers.

Frequently asked questions

Who qualifies for the strongest screening recommendation?

Asymptomatic people aged 55 to 77 who have smoked 30 pack-years or more and still smoke or quit within the past 15 years.

When should screening not be done?

When people fall outside the age, pack-year or quit-time criteria without a projected high net benefit, or when comorbidities substantially limit life expectancy or the ability to tolerate evaluation or treatment.

What counts as a positive scan?

Each program should define it by the size of a solid or part-solid nodule, with a threshold of 4 mm, 5 mm or 6 mm in diameter.

Source

Mazzone PJ, Silvestri GA, Souter LH, Caverly TJ, Kanne JP, Katki HA, et al. Screening for Lung Cancer: CHEST Guideline and Expert Panel Report. Chest 2021;160(5):e427-e494. doi:10.1016/j.chest.2021.06.063. This summary was prepared by Medpresso from the original publication and is not a substitute for the full text or for medical advice.