To evaluate efficacy in patients with brain metastasis (BM) on entry into the lapatinib expanded access program (LEAP).
LEAP is a worldwide, single-arm, open-label study. HER2-positive, locally-advanced or metastatic breast cancer patients with progression after an anthracycline, taxane, and trastuzumab were eligible. Patients received capecitabine 2000mg/m2 daily in two divided doses, days 1–14, every 21days and lapatinib 1250mg once daily.
Among 186 patients enrolled in 6 Korean centers, 58 had BM. Progression-free survival (PFS) was 18.7weeks in patients with BM and 19.4weeks without BM (P=0.88). In patients with BM, brain response was synchronized with systemic responses (P=0.0001). Overall survival (OS) was 48.9weeks in patients with BM and 64.6weeks without BM (P=0.23). Multivariable analysis found hormone receptor positivity (P=0.003) and clinical benefit rate (CBR) of combined systemic and brain disease (P<0.0001) significantly associated with prolonged brain PFS, and CBR of combined systemic and brain disease (P=0.03) and longer trastuzumab use (P=0.047) associated with prolonged OS in patients with BM; prior capecitabine did not affect PFS or OS in patients with BM.
Lapatinib plus capecitabine is equally effective in patients with or without BM.
Keywords: Brain Metastasis, HER2-positive Metastatic Breast Cancer, Lapatinib and Capecitabine Therapy, LEAP