Treatment of NSCLC
Treatment of NSCLC
The graphic shows the therapies for the specific stages of NSCLC. Patients with stage I, II, or III NSCLC are generally treated with curative intent using surgery, chemotherapy, radiation therapy, or a combined modality approach (see graphic). Palliative systemic radiotherapy is appropriate for patients with stage IV disease.
Multiple single cytotoxic agents have antitumor activity in patients with advanced NSCLC. The most important of these are the platinum compounds cisplatin and carboplatin. Other cytotoxic agents used here are taxanes (paclitaxel and docetaxel), vinorelbine, gemcitabine, and pemetrexed.
Two-drug chemotherapy regimens always contain a platinum compound. In all stages two compounds are used in patients with good performance.
Cytotoxic chemotherapy prolongs survival in patients with stage IV non-small cell lung cancer (NSCLC) without significantly impairing quality of life. In addition, the development of new biologic agents (bevacizumab, cetuximab) and tyrosine kinase inhibitors (erlotinib, gefitinib) has led to the combination of new promising approaches.
Biologicals are specifically targeted at growth factors and their receptors at the tumor cells. Patients with EGFR-positive tumors can be treated with an EGFR tyrosine kinase inhibitor (erlotinib or gefitinib) as initial therapy rather than cytotoxic chemotherapy. These drugs prevent the effects of EGFR stimulation and thus their signal transduction pathways and subsequent regulation of cell proliferation, apoptosis, angiogenesis, adhesion, and motility. Cetuximab is a monoclonal antibody that binds to the EGFR, thus providing an alternative way to interfere with the epidermal growth factor pathway.
In NSCLC, high levels of the angiogenic factor vascular endothelial growth factor (VEGF) are associated with a poor prognosis, suggesting that treatment targeted toward this pathway might be useful therapeutically. Bevacizumab is a recombinant monoclonal antibody that binds VEGF, thereby preventing its interaction with the VEGF receptor. Combination of bevacizumab and the paclitaxel plus carboplatin doublet offers a higher response rate compar.