Does UKLS strategy increase the yield of screen-detected lung cancers? A comparison with ITALUNG The optimal strategy to increase the benefit of low dose computed tomograph (LDCT) screening of lung cancer in terms of as high as possible number of discov- ered cancers and to reduce the costs, in terms of as low as possible number of LDCT examinations and of interventions on benign lesions, is not established. Field and co-workers recently reported 1 the results of lung cancer screening with LDCT in the UKLS RCT pilot study that selected eligible subjects with a validated individual risk prediction model, invited potential candidates by mail and applied the Wald Single Screen Design 2 with nodule management based on volumetry. 1 We compared (table 1) some data of UKLS RCT pilot study with those of ITALUNG RCT that selected eligible sub- jects based on age and smoking history, invited potential candidates by mail and involved four annual LDCT screening rounds with nodule management based on diameter measurement. 34 In the UKLS pilot study, higher rates of screen-detected primary lung cancers (2.1% vs 1.7%) and of stage I–II lesions (86% vs 68%) were observed. These fea- tures may be accounted for different popu- lation’s characteristics including older age (mean 67 vs 61 years), higher male/female ratio (3.01 vs 1.79), higher frequency of asbestos exposure (36.0% vs 6.6%), higher prevalence of respiratory disease (52.1% vs 35.1%) and familial history for lung cancer (24.6% vs 16.8%) in UKLS screens. In particular, prevalence of lung cancer at LDCT screening can be as high as 4.2% in subjects exposed to asbestos. 5 On the other hand, the majority of the screens in UKLS were former smokers, whereas they were current smokers in ITALUNG. Twelve-month LDCT were obtained in Table 1 Screens risk profile and results of LDCT in pilot UKLS and ITALUNG RCT Pilot UKLS ITALUNG Age (years) of selected subjects 50–75 55–69 Eligibility criteria 5-year lung cancer risk of ≥5%, based on the Liverpool Lung Project v2 risk prediction model Smokers or former smokers of ≥20 pack/years Sample size Control arm 2027 1593 Screened arm 2028 1613 Screeens’ characteristics Mean age at randomisation (years SD) 67 (4.1) 61 (4.2) Gender (male/female ratio) 1529/499 (3.06) 1035/578 (1.79) Current smokers 777 (38.3%) 1060 (65.7%) Ex-smokers 1249 (61.6%) 553 (34.3%) Never smokers 2 (0.1%) 0 Smoking duration 10–19 years* 117 (5.8%) 1 (0.06%) 20+ years* 1895 (93.4%) 1612 (99.94%) Unknown* 14 (0.7%) 0 % Asbestos exposed 763 (36%) 93 (6.6%)† % With history of respiratory disease‡ 1056 (52.1%) 494 (35.1%)† % With history of blood cancer§ 26 (1.28%) Not eligible % With history of solid tumour¶ 378 (18.6%) Not eligible % With family history of lung cancer 498 (24.6%) 237 (16.8%)† % With family history of other cancer (not lung)** 1026 (50.6%) 640 (45.5%)† Baseline LDCT completed 1994 (98.3%) 1406 (87.2%) LDCT detected primary lung cancers 42/1994 (2.1%) 25/1406 (1.7%)†† At baseline scan 34/1994 (1.7%) 21/1406 (1.4%) Adenocarcinoma 25/42 (59.5%) 13/25 (52.0%) Stage I lung cancer 28/42 (66.7%) 14/25 (56.0%) Stage I or II lung cancer 36/42 (85.7%) 17/25 (68.0%) Surgical resection 35/42 (83.3%) 17/25 (68.0%) Subjects undergoing 12-month scan LDCT 1015/1994 (50.9%)‡‡ 1356 (96.4%) Overall category 3 and 4 nodules§§ 536/1994 (26.8%) 426/1406 (30.2%) Of these, subjects found to have lung cancer 42/536 (7.8%) 25/426 (5.8%) Surgical resection for benign disease 4/39 (10.3%) 1/21 (4.7%)¶¶ *All smoking (cigarettes, cigars, pipes) duration figures refer to current and ex-smokers combined. †Information available in 1406 subjects undergoing baseline LDCT. ‡Asthma, bronchitis, TB, pneumonia, COPD or emphysema. §Leukaemia or lymphoma, including Hodgkin’s. ¶Cancers of brain, head and neck, oesophagus, breast, colon or ‘other’. ††Data of ITALUNG refer to baseline and first annual repeat LDCT screening rounds. ‡‡Due to evidence at baseline of nodules >3 mm diameter. **Cancers of brain, head and neck, oesophagus, breast, colon or ‘other’. §§Category 3 nodules correspond to: solid nodules with 5–9.9 mm diameter; part-solid nodules with non-solid component >5 mm diameter and solid component of 3–9.9 mm diameter; non-solid nodules ≥5 mm diameter. Category 4 nodules correspond to: solid nodules ≥10 mm diameter; part-solid nodules with solid component ≥10 mm diameter. ¶¶One case of atypical adenomatous hyperplasia reclassified as adenocarcinoma in 2015. 950 Thorax October 2016 Vol 71 No 10 Research letter on June 5, 2020 by guest. Protected by copyright. http://thorax.bmj.com/ Thorax: first published as 10.1136/thoraxjnl-2016-208409 on 23 May 2016. Downloaded from