Clinical course of asymptomatic small enhancing brain nodules in patients with nonsmall cell lung cancer: do we have to follow them up?. Issue 3 (14th September 2020) - Lee, Hyun Woo
Aims: Brain magnetic resonance imaging (MRI) is recommended during the initial work-up for nonsmall cell lung cancer (NSCLC). Although small enhancing brain nodules not radiologically confirmed as metastatic lesions have often been detected, their clinical course has not been well studied. Methods: This nested case–control study included NSCLC patients who had small enhancing brain nodules detected by serial brain MRIs from January 2014 through December 2018 at a tertiary university hospital. Small enhancing brain nodules were defined as round enhancing nodules of ≤10 mm diameter without oedema in thin-section (1 mm) contrast MRIs. The incidence, natural course and risk factors of growing nodules were evaluated. Results: A total of 171 small enhancing brain nodules in 123 patients were observed over an average of 22.1 months. The incidence of nodule growth was 49.1% with mean growth rate of 11 mm·year −1 . We found that 25.0% of the growing nodules contributed to clinical upstaging compared to the initial stage. Cerebral events were more common in growing nodules; therefore, local therapy was performed more often. However, there was no difference in the cerebral event-related mortality. Nodule growth was more frequent in younger individuals, multiple nodules, advanced disease, poorly differentiated carcinoma, rim enhancement and larger initial size. In multivariable analysis, predictors of growth were N stage ≥1, existence of epidermal growth factor receptor mutation and larger initial size. Conclusion: Considering the clinical course of small enhancing brain nodules, more intensive evaluation is required for early detection and pre-emptive intervention when accompanied by risk factors. Small enhancing brain nodules are found in 4.1% of NSCLC. Growth is found in the 49.1% with a rate of 11.0 mm per year. Lymph node metastasis, EGFR mutation and larger diameter are risk factors for growth. https://bit.ly/2ALqhhM