The biology of tumor invasion, angiogenesis and lymph node metastasis

It is now well established that the development of cervical metastases, in particular those with extranodal extension of tumor, negatively impacts both regional control and survival of patients with laryngeal carcinoma. This chapter will begin with an introduction of the important molecular events associated with the transition of the squamous epithelium of the upper aerodigestive tract to metastatic squamous cell carcinoma. We will then review the critical cellular events identified as the tumor progresses from an in situ to invasive and finally a metastatic head and neck squamous cell carcinoma. Finally we will review data from our own and other laboratories which are studying the process of new blood vessel growth (angiogenesis) induced by tumor-derived growth factors. As we develop a better understanding of the cellular and molecular mechanisms of metastasis in head and neck squamous cell carcinoma, new therapies effective at preventing the development of secondary tumors can be realized ultimately increasing the patient's survival.