1. ¹Roy Castle Lung Cancer Research Programme, University of Liverpool Cancer Research Centre, Liverpool, L3 9TA, UK
2. ²Cancer Research UK Centre for Epidemiology, Mathematics and Statistics Wolfson Institute of Preventive Medicine, London, EC1M 6BQ, UK
3. ³Institute of Occupational Medicine, Research Avenue North, Riccarton, Edinburgh, EH14 4AP, UK
4. ⁴Department of Thoracic Surgery, The Cardiothoracic Centre, Liverpool, L14 3PE, UK

Correspondence: Professor JK Field, Roy Castle Lung Cancer Research Program, Division of Surgery & Oncology, University of Liverpool Cancer Research Centre, University of Liverpool, 200 London Road, Liverpool, L3 9TA, UK. E-mail: J.K.Field@liv.ac.uk

⁵These authors contributed equally to this work

Received 10 July 2007; Revised 19 October 2007; Accepted 25 November 2007; Published online 18 December 2007.

Abstract

Using a model-based approach, we estimated the probability that an individual, with a specified combination of risk factors, would develop lung cancer within a 5-year period.

Data from 579 lung cancer cases and 1157 age- and sex-matched population-based controls were available for this analysis. Significant risk factors were fitted into multivariate conditional logistic regression models. The final multivariate model was combined with age-standardised lung cancer incidence data to calculate absolute risk estimates.

Combinations of lifestyle risk factors were modelled to create risk profiles. For example, a 77-year-old male non-smoker, with a family history of lung cancer (early onset) and occupational exposure to asbestos has an absolute risk of 3.17% (95% CI, 1.67–5.95). Choosing a 2.5% cutoff to trigger increased surveillance, gave a sensitivity of 0.62 and specificity of 0.70, while a 6.0% cutoff gave a sensitivity of 0.34 and specificity of 0.90. A 10-fold cross validation produced an AUC statistic of 0.70, indicating good discrimination. If independent validation studies confirm these results, the LLP risk models' application as the first stage in an early detection strategy is a logical evolution in patient care.