The UK National Screening Committee recently approved a national programme for lung cancer screening (LCS) by low-dose CT (LDCT).1 Measures that will reduce burden on downstream clinical care in the National Health Service (NHS) are therefore greatly welcomed. This need is further amplified in the postpandemic era where services are already stretched and waiting times are higher than ever.2 In the current issue of Thorax, Creamer et al present results from the SUMMIT study’s prospective LCS nodule management algorithm that aims to do exactly that.3 Their protocol differs from other LCS protocols in that they increase the size threshold at which to refer participants with growing solid lung nodules from the LCS programme to lung cancer services.

There are various available protocols for the management of screen-detected and incidental pulmonary nodules. Table 1 summarises the latest iterations of the nodule management guidelines from American College of Radiology Lung CT Screening Reporting and Data System (Lung-RADS),4 the Fleischner Society5 and the NHS England Targeted Lung Health Checks Programme.6 The latter is largely based on the British Thoracic Society guidelines on pulmonary nodules (2015),7 which was the first to incorporate volumetry. Lung-RADS and the Fleischner Society later followed suit.

Comparison of algorithms for management of screen-detected and incidentally detected solid nodules

For solid nodules, current LCS protocols direct referral of participants with an LDCT nodule >8 mm or >250–300 mm3 (depending on protocol used) to the local lung cancer multidisciplinary team or tumour board for further investigation and workup. Nodules smaller than this size are too small for positron emission tomography (PET)-CT or biopsy, and so …