Optimal Starting Age for Lung Cancer Screening with Low-dose CT: A Population Level Analysis

Date 24 November 2018
Event ESMO Asia 2018 Congress
Session Poster display - Cocktail
Topics Imaging
Thoracic Malignancies
Presenter Cai Chen Li
Citation Annals of Oncology (2018) 29 (suppl_9): ix139-ix142. 10.1093/annonc/mdy445
Authors C.C.C. Li1, H.R. Liang2, Y. Zhao2, Y.K. Wen1, G.P. Qiu1, N.S. Zhong1, J.X. He2, W.H. Liang1
  • 1China State Key Laboratory Of Respiratory Disease & National Clinical Research Center For Respiratory Disease, Guangzhou/china, The 1st Affiliated Hospital of Guangzhou Medical University, 510000 - Guangzhou/CN
  • 2Guangzhou Institute Of Respiratory Disease & China State Key Laboratory Of Respiratory Disease, Guangzhou/china, The 1st Affiliated Hospital of Guangzhou Medical University, 510000 - Guangzhou/CN



Early detection by screening provides the only opportunity to cure lung cancer. Low-dose computed tomography (LDCT) has become the standard approach for lung cancer screening. However, the optimal starting age of screening remained unclear. Therefore, we summarized the results of lung cancer screening trials using LDCT to explore the relationship between the starting age and the efficiency of screening.


We searched relevant studies from electronic databases. Number of participants, baseline detection rates of all nodules and lung cancer (all and stage I) were extracted from eligible studies. Single-arm syntheses weighted by sample size were performed using Meta-Analyst software. Chi2 test was used to compare the detection rates between different age groups under Bonferroni adjustment.


A total of 26 studies involving 117,586 participants were included. As expected, the detection rate of all lung cancer cases as well as stage I diseases increased with age. However, the proportion of stage I diseases in all lung cancer cases being detected declined with age and was significantly higher in age 40 and 45 group than the age 50 (P = 0.001) and 55 groups (P = 0.001), but there was no significant difference between 40 and 45 group (P = 0.196). Meanwhile, the ratio of early lung cancer to all nodules being detected, an index showing the true positivity out of the misleading background, was also higher in the population who start screening before 50 years old. Data were summarized in the table below.Table: 456P

Screening Starting AgeAll Lung Cancer/ No. ScreenedStage I/ No. ScreenedStage I/ All Lung CancerStage I/ All Nodules
40 (n = 48,749)0.94% (0.65%-1.37%)0.76% (0.49%-1.07%)78.74% (68.43%-86.35%)3.36% (1.69%-6.56%)
45 (n = 7,913)1.05% (0.55%-2.01%)0.78% (0.25%-2.39%)81.64% (28.42%-98.03%)3.46% (1.13%-10.13%)
50 (n = 29,981)1.19% (0.85%-1.66%)0.81% (0.57%-1.13%)69.43% (61.23%-76.57%)1.87% (1.37%-2.55%)
55 (n = 30,943)1.65% (1.19%-2.29%)1.06% (0.84%-1.33%)50.61% (46.95%-54.27%)2.32% (1.46%-3.66%)


In order to discover more early stage diseases when they can be cured, the starting age for lung cancer screening should be 45. In addition, starting screening at younger age might simplify the diagnosis in a cleaner background. Determination of the optimal starting age needs more analysis based on the original data, under comprehensive consideration of the survival benefits, costs and impact of different risk factors.

Editorial acknowledgement

Clinical trial identification

Legal entity responsible for the study

The First Affiliated Hospital of Guangzhou Medical University.


Has not received any funding.


All authors have declared no conflicts of interest.