Smoking and lung cancer

Smoking has been firmly linked to lung cancer for some time now. The first good study on this was by Doll and Hill who followed groups of GPs in the UK, and were able to show the following:

• there was a dose response relationship between smoking and lung cancer, both on duration and amount of cigarettes smoked
• there was no difference between the town and country
• stopping smoking results in a continual decline in the risk

A Canadian study found that

• 172/1,000 of male current smokers will eventually develop lung cancer
• similar probability among female current smokers was 116/1,000
• for those who never smoked on a regular basis the lifetime risk was substantially reduced.
  • only 13/1,000 males and 14/1,000 females in this category will develop lung cancer

Smoking is also an aetiological factor in the development of oesophageal, bladder and prostatic cancer

Smoking cessation after diagnosis materially improved overall and progression-free survival among current smokers with early-stage lung cancer (2)

• prospective Russian cohort study found higher overall survival time among patients who quit smoking vs continued smoking (6.6vs4.8yrs, respectively; P=0.001), 5-year overall survival (60.6%vs48.6%; P=0.001) and progression-free survival (54.4%vs43.8%; P=0.004)

Reference:

• Villeneuve PJ, Mao Y. Lifetime probability of developing lung cancer, by smoking status, Canada. Canadian Journal of Public Health = Revue Canadienne de Sante Publique. 1994 Nov-Dec;85(6):385-388. PMID: 7895211.
• Mahdi Sheikh, Anush Mukeriya, Oxana Shangina, et al. Postdiagnosis Smoking Cessation and Reduced Risk for Lung Cancer Progression and Mortality: A Prospective Cohort Study. Ann Intern Med. [Epub ahead of print 27 July 2021]. doi:10.7326/M21-0252