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A5972 - Lung Cancer Patients Who Quitted Smoking Cigarette Over 15 Years Prior to Diagnosis Are at the Same Risk of Death as Those Who Met the USPSTS Criteria for Lung Cancer Screening
Author Block: L. Luo1, D. E. Midthun2, Y. Wang3, D. Liu4, S. M. Stoddard1, Q. Li5, J. A. Wampfler2, P. Yang6; 1Mayo Clinic College of Medicine, Rochester, MN, United States, 2Mayo Clinic, Rochester, MN, United States, 3Wenzhou Medical University, Wenzhou, China, 4West China Hospital Sichuan University, chengdu, China, 5Shanghai Pulmonary Hospital Tongji University, Shanghai, China, 6Health Sciences Research, Mayo Clinic, Rochester, MN, United States.
Rationale: A comparative modeling study for the U.S. Preventive Services Task Force (USPSTF) predicted that more than 18, 000 lung cancer deaths per year could be avoided in the United States if screening could be widely used for population who are 55-80 years of age, had at least a 30-pack-year smoking history, and if a former smoker, had quit no more than 15 years. [Ann Intern Med. 2014. PMID: 24379002]. However, our previous studies showed that up to two-thirds of newly-diagnosed lung cancer patients did not meet this criterion [JAMA. PMID: 25710663], in whom patients otherwise fit but having quit smoking for 15 to 30 years formed the largest proportion [J Thorac Oncol. 2016. PMID: 26811226]. In this study, we further evaluated the risk of death between lung cancer patients who met USPSTF screening criteria and who did not meet criteria due to longer quitting years. Methods: A total of 8031 primary lung cancer patients who aged 55-80 years, with at least a 30-pack-year smoking history and either are current smokers or have quit smoking within the 30 years were drawn from a community cohort (n=863) or a hospital cohort (n=7168), and divided into USPSTF screening group and long-term quitters group (patients who quit smoking 15-30 years) to assess the risk of death. Models were developed in the community cohort and validated independently in the hospital cohort with adjustment of the following covariates: age, sex, race, cigarette smoking history, tumor histology and stage, and treatment modalities. Results: In the community cohort, long-term Quitters were at a similar risk of death from lung cancer when compared with lung cancer patients who met the USPSTF screening criteria after adjusting for the covariates (hazard ratio [HR] =0.95, 95% confidence interval [CI], 0.74-1.24, p=0.73). More strikingly, in the hospital cohort, Long-term Quitters are at the identical risk of death to those who met the USPSTF screening criteria (HR=1.00, 95% CI, 0.92-1.09, p=0.92). Conclusions: Patients aged 55-80 years, with 30 or more pack-years of cigarette smoking but quit smoking for 15 to 30 years are at the same risk of death from lung cancer as patients who meet USPSTF screening criteria. Our findings suggest that it may be appropriate to extend the quitting smoking criterion of USPSTF from under 15 to up to 30 years for lung cancer screening as the biology of lung cancer in this cohort manifest a similar lethality.