S72 Is there merit in CT surveillance of non-discrete inflammatory change seen on CT thorax?

Introduction Lung nodules are a common incidental finding on CT imaging, with many nodules requiring surveillance. CT surveillance is sometimes also recommended for CT changes that do not represent discrete nodules, including consolidation and inflammatory changes that may not be visible on chest x-ray. We aim to assess the outcomes of our CT surveillance programme. Methods We reviewed all patients under surveillance through our virtual ‘nodule’ clinic at any time between April 2015 and November 2018. The index CT report that recommended surveillance was reviewed and coded according to whether this described (1) the presence any discrete pulmonary nodule; and (2) the presence of presumed benign inflammatory change. We identified subsequent lung cancer diagnoses from collected for the National Lung Cancer Audit submissions. Results 1249 patients were identified, with index CT scans from May 2010 to September 2018. Rates of lung cancer diagnosis in each group are shown in table 1. 98 patients had surveillance for reported inflammatory change in the absence of a discrete nodule, 3 (2.6%) of whom subsequently developed lung cancer. Index CT scans in these cases were reviewed by a consultant chest radiologist, who concluded: Case 1) Reported ‘peripheral consolidation’ was visible on CXR. Case 2) Reported ‘nodular consolidation’ represents as a discrete solid nodule. Case 3) Reported ‘ill-defined consolidation’ represents a discrete part-solid nodule. Conclusion 6.8% of patients under surveillance in our virtual nodule clinic were diagnosed with lung cancer within 3 years. The incidence of lung cancer in patients under surveillance for inflammatory change without a true nodule is very low. Chest x-ray surveillance should be considered in these cases, where feasible.