Incidence and Risk Factors for Brain Metastasis in Patients with Presumed Early-stage Lung Cancer = Incidence and Risk Factors for Brain Metastasis in Patients with Presumed Early-stage Lung Cancer

다국어 초록 (Multilingual Abstract)

Purpose
Regarding whether brain magnetic resonance imaging (MRI) should be routine in patients with presumed early-stage lung cancer, guideline recommendations are inconsistent. In this regard, we performed the study to evaluate the incidence and risk factors for brain metastasis (BM) in patients with presumed early-stage non-small cell lung cancer (NSCLC).
Method
A review of the medical charts of consecutive NSCLC patients diagnosed between January 2006 and May 2020 was performed. We identified 1,382 patients who were diagnosed with NSCLC with clinical stage of T1/2aN0M0 apart from brain MRI result (Figure 1). Firth’s bias-reduced logistic regression were used to assess predictors of BM. Fisher’s exact test with the minimum p-value approach was used to determine the optimal cut-off value in tumor size predicting BM.
Result
Six hundred fifty-one patients (47.1%) were female; mean ± SD age was 64.3 ± 10.4 years. Nine hundred forty-nine patients (68.7%) underwent brain MRI during staging, and 34 patients (3.6%) were shown to have BM. Firth’s bias-reduced logistic regression model showed that tumor size in millimeters (OR 1.056; 95% CI 1.009-1.106) was a single predictor for presence of BM. A cut-off value of 3.5 cm in tumor size was predictive for BM in our cohort (OR 4.538; CI 95% 1.977-9.650). The median overall survival of the participants with BM was 5.5 year and 5-year survival rate was 59.8%.
Conclusions
Given the incidence and favorable outcome of BM in patients with presumed early-stage NSCLC, routine screening of brain MRI might be considered, especially in patients with tumor size of ≥3.5 cm.