In a retrospective analysis of the EMILIA study, the rate of central nervous system (CNS) progression in patients with human epidermal growth factor receptor 2-positive metastatic breast cancer was similar for trastuzumab emtansine (T-DM1) and for capecitabine–lapatinib. In patients with treated, asymptomatic CNS metastases at baseline, T-DM1 was associated with significantly improved overall survival versus capecitabine–lapatinib.

Purpose HER2-positive breast cancer is heterogeneous. Some tumors express mutations, like activating PIK3CA mutations or reduced PTEN expression, that negatively correlate with response to HER2-targeted therapies. In this exploratory analysis, we investigated whether the efficacy of trastuzumab emtansine (T-DM1), an antibody–drug conjugate comprised of the cytotoxic agent DM1 linked to the HER2-targeted antibody trastuzumab, was correlated with the expression of specific biomarkers in the phase III EMILIA study. Experimental Design Tumors were evaluated for HER2 (n = 866), EGFR (n = 832), and HER3 (n = 860) mRNA expression by quantitative reverse transcriptase PCR; for PTEN protein expression (n = 271) by IHC; and for PIK3CA mutations (n = 259) using a mutation detection kit. Survival outcomes were analyzed by biomarker subgroups. T-DM1 was also tested on cell lines and in breast cancer xenograft models containing PIK3CA mutations. Results Longer progression-free survival (PFS) and overall survival (OS) were observed with T-DM1 compared with capecitabine plus lapatinib in all biomarker subgroups. PIK3CA mutations were associated with shorter median PFS (mutant vs. wild type: 4.3 vs. 6.4 months) and OS (17.3 vs. 27.8 months) in capecitabine plus lapatinib–treated patients, but not in T-DM1-treated patients (PFS, 10.9 vs. 9.8 months; OS, not reached in mutant or wild type). T-DM1 showed potent activity in cell lines and xenograft models with PIK3CA mutations. Conclusions Although other standard HER2-directed therapies are less effective in tumors with PI3KCA mutations, T-DM1 appears to be effective in both PI3KCA-mutated and wild-type tumors.

A B S T R A C T PurposeSevere (grade Ն 3) pulmonary hemorrhage (PH) in advanced non-small-cell lung cancer was observed in two prospective, randomized, phase II (N ϭ 99) and phase III (N ϭ 878) trials of bevacizumab plus carboplatin and paclitaxel. Retrospective case-control and cohort analyses were conducted to identify associated radiographic and clinical risk factors for PH. Patients and MethodsSix patients with PH from the phase II trial, 15 potential PH patients with hemorrhage at any site from the phase III trial, and their matched controls were evaluated with review of baseline and on-treatment radiographs by an independent radiology facility, blinded to patient/control status. Patients with severe (grade Ն 3) PH from each trial were matched with up to three controls based on sex, age group, histology (phase II), or sex and age group (phase III). ResultsSeven PH patients in the phase III trial were identified as severe PH. Six of the patients were early onset (occurred Ͻ 150 days of initiating bevacizumab) and one was late onset. Baseline tumor cavitation, not tumor location, was identified as the only potential risk factor for patients with early onset. Combined analysis of severe PH patients from the phase II and phase III trials (n ϭ 13), compared with their pooled matched controls (n ϭ 42), did not identify any additional baseline radiographic or clinical variables associated with PH. ConclusionPH was an uncommon event. Based on these analyses, baseline tumor cavitation may be a potential risk factor for PH. No other baseline clinical variables were predictive for PH although the number of events was small.