T Matys, R Drury, S David, DM Rassl, W Qian, RC Rintoul, NJ Screaton
OBJECTIVES: Although detection of brain metastasis can change treatment intent in non-small cell lung carcinoma (NSCLC), head imaging is not routinely performed during initial staging. In our previous study, 4.8% of patients considered for surgical treatment had asymptomatic synchronous brain metastases, encouraging us to include contrast-enhanced head CT (CE-CT) in our routine staging protocol. We present results from a large cohort of potentially resectable NSCLC patients imaged irrespective of the presence of neurological symptoms. MATERIALS AND METHODS: Patients with newly diagnosed NSCLC were identified from Royal Papworth Hospital registries. Data regarding the clinical stage (7th edition TNM), neurological symptoms and imaging findings were retrieved from clinical records. RESULTS: 1074 NSCLC patients considered potentially resectable based on the initial staging CT of the chest and abdomen (stage IA-IIIB) were included. Synchronous brain metastases were detected by CE-CT in 23 patients (2.1%); the rate of positive findings increased with stage, ranging from 0.7% (IA) to 2.6% (IIIA) (p = 0.023). The majority of metastases were asymptomatic (19 of 23, 82.6%). Asymptomatic brain lesions were smaller than symptomatic (13.3 ± 4.8 vs 24.8 ± 8.2 mm; p < 0.01); in both groups, the most frequent location was frontal lobe. CONCLUSION: Routine CE-CT detected synchronous brain metastases in approximately 2% of NSCLC patients eligible for radical surgical treatment. The majority of the metastatic lesions were asymptomatic. With the exception of stage IA in which the detection rate is very low, CE-CT could therefore be useful in routine NSCLC staging.