Epidermal growth factor receptor tyrosine-kinase inhibitor treatment resistance in non-small cell lung cancer: biological basis and therapeutic strategies.

Lung cancer remains the leading cause of cancer-related death. Non-small cell lung cancer (NSCLC) represents 85 % of all lung cancer cases and it is classified into three major subtypes: adenocarcinoma, squamous cell carcinoma and large-cell carcinoma. In the past years, molecular-targeted therapies have been developed in order to improve response, survival and quality of life in patients with advanced NSCLC. Lung cancers harboring mutations in the epidermal growth factor receptor (EGFR) respond to EGFR tyrosine-kinase inhibitors (TKIs). However, virtually all patients with initial response relapse due to acquired resistance. Better understanding the biology of these tumors and mechanisms of EGFR TKIs resistance could shed some light on research of new therapeutic options in this setting. This review aims to emphasize on EGFR involved lung cancer pathway, primary and acquired mechanisms of TKIs resistance, and discuss agents currently used in clinical development in this emerging scenario.

Cardiac safety of adjuvant pegylated liposomal doxorubicin with concurrent trastuzumab: a randomized phase II trial.

BACKGROUND: The cardiac safety of trastuzumab concurrent with pegylated liposomal doxorubicin (PLD) in an adjuvant breast cancer treatment regimen is unknown. PATIENTS AND METHODS: Women with resected node-positive or intermediate-risk node-negative HER2 overexpressing breast cancer and baseline left ventricular ejection fraction (LVEF)≥55% were randomized (1:2) to doxorubicin 60 mg/m2 (A)+cyclophosphamide 600 mg/m2 (C) every 21 days (q21d) for four cycles or PLD 35 mg/m2+C q21d+trastuzumab 2 mg/kg weekly (H) for 12 weeks. Both groups then received paclitaxel (Taxol, T) 80 mg/m2 with H for 12 weeks followed by H to complete 1 year. The primary end point was cardiac event rate or inability to administer 1 year of trastuzumab. RESULTS: Of 181 randomized patients, 179 underwent cardiac analysis. The incidence of cardiac toxicity or inability to administer trastuzumab due to cardiotoxicity was 18.6% [n=11; 95% confidence interval (CI) 9.7% to 30.9%] with A+C→T+H and 4.2% (n=5; 95% CI 1.4% to 9.5%) with PLD+C+H→T+H (P=0.0036). All events, except one, were asymptomatic systolic dysfunction or mildly symptomatic heart failure. Mean absolute LVEF reduction at cycle 8 was greater with doxorubicin (5.6% versus 2.1%; P=0.0014). CONCLUSION: PLD+C+H→T+H is feasible and results in lower early cardiotoxicity rates compared with A+C→T+H.

First-line bevacizumab-containing therapy for breast cancer: results in patients aged≥70 years treated in the ATHENA study.

BACKGROUND: There are limited data on treatment outcomes in the growing population of elderly patients with locally recurrent/metastatic breast cancer (LR/mBC). To gain information on first-line bevacizumab combined with chemotherapy in the elderly, we analyzed data from the ATHENA trial in routine oncology practice. PATIENTS AND METHODS: Patients with human epidermal growth factor receptor-2-negative LR/mBC received first-line bevacizumab with standard chemotherapy until disease progression, unacceptable toxicity, or physician/patient decision. We carried out a subgroup analysis of safety and efficacy in patients aged≥70 years. Possible correlations between tolerability and baseline comorbidities or Eastern Cooperative Oncology Group status were explored. RESULTS: Bevacizumab was combined with single-agent paclitaxel in 46% of older patients. Only hypertension and proteinuria were more common in older than in younger patients (grade≥3 hypertension: 6.9% versus 4.2%, respectively; grade≥3 proteinuria: 4.0% versus 1.5%, respectively). Grade≥3 arterial/venous thromboembolism occurred in 2.9% versus 3.3%, respectively. Further analysis revealed no relationship between baseline presence and severity of hypertension and risk of developing hypertension during bevacizumab-containing therapy. Median time to progression was 10.4 months in patients aged≥70 years. CONCLUSIONS: These findings suggest that bevacizumab-containing therapy is tolerable and active in patients aged≥70 years. Hypertension was more common than in younger patients but was manageable. We find no evidence precluding the use of bevacizumab in older patients, including those with hypertension, although age may influence chemotherapy choice.