ERCC1 influence on the incidence of brain metastases in patients with non-squamous NSCLC treated with adjuvant cisplatin-based chemotherapy.

BACKGROUND: We recently demonstrated that excision repair cross-complementing group 1 protein (ERCC1) is predictive of adjuvant cisplatin-based chemotherapy benefit in resected non-small-cell lung cancer (NSCLC). Non-squamous cell carcinomas (non-SCCs) carry an increased risk of brain metastases (BMs). We hypothesised that there might be an increased incidence of BMs in ERCC1-negative non-SCCs when treated with adjuvant cisplatin-based chemotherapy.

PATIENTS AND METHODS: Incidence of BMs and histoclinical parameters were analysed in a population of 761 patients enrolled in the International Adjuvant Lung Cancer Trial. A subgroup analysis was carried out in patients with ERCC1-negative non-SCCs.

RESULTS: Of 761 patients, 98 developed BMs alone or in association with other metastatic sites, with a 5-year incidence rate of 18.0% (14.7%-21.8%). In the multivariate analysis, the clinical parameters associated with the occurrence of BMs were the nodal status (P = 0.02) and histological type [give hazard ratio (HR) for non-squamous to quantify introduction assertion, P = 0.002]. Chemotherapy had no effect on BMs [HR = 1.4 (0.90-2.1), P = 0.14]. In patients with non-SCC histology (n = 335), adjuvant chemotherapy was associated with an increased risk of BMs [HR = 2.1 (1.01-4.3), P = 0.04] for ERCC1-negative tumours, whereas there was no evidence of an effect on BMs for ERCC1-positive tumours [HR = 1.1 (0.38-3.0), P = 0.90]. Nevertheless, these two effects are not different (P = 0.30 for interaction) possibly due to a lack of power in this subgroup.

CONCLUSIONS: This study suggests that adjuvant cisplatin-based chemotherapy is associated with an increased risk of BMs in patients with resected chemosensitive non-SCCs. If confirmed, these data could provide a rationale for new follow-up and/or prophylactic strategies.