ERBB2 and lung cancer: The prognostic and predictive importance of these receptors and their downstream signalling pathways has been demonstrated in other malignancies and has led to the development of targeted therapies such as monoclonal antibodies (e.g cetuximab, panitunimab, trastuzumab) and small molecules tyrosine kinase receptor inhibitors (e.g gefitinib, erlotinib and more recently dual EGFR/HER2-neu inhibitors such as lapatinib) in lung cancer, colon cancer and breast cancer.