The objective of this study is to evaluate the relationship between serum nicotine levels and tumor response of squamous cell cancers of the head and neck (SCCHN) to radiotherapy alone or in combination with chemotherapy. Correlation of RECIST response, volumatic response, pathologic response (in patients receiving post-treatment neck dissection), and hemodynamic response (tumor oxygenation and blood flow) will be performed.

The exposure to tobacco related carcinogens is highly dependent upon dose as well as interindividual characteristics of metabolism. Risk assessment of carcinogenic profiles for nicotine and its individual metabolites is complicated by interindividual variations in nicotine metabolism associated with quantitative nicotine exposure, gender, genetic polymorphisms, and behavioral and environmentally induced differences in nicotine metabolizing enzyme activities. Consequently, differences in smoking behavior or tobacco use have been correlated to differences in nicotine metabolism resulting in cessation strategies based upon tobacco use, nicotine dependence, and behavioral modification. Cotinine has been shown to be a reliable marker of nicotine exposure and more reflective of recent rather than acute nicotine use with better assessment of baseline nicotine levels. Therefore, subjects will have blood samples drawn weekly during radiation for cotinine analysis. Radiation therapy efficacy is known to be dependent on tissue oxygen status. Since therapeutic treatment is less efficacious in patients with poorly vascularized/ hypoxic tumors, it is desirable to identify and target such patients for special treatment. Recent magnetic resonance imaging and computed tomography investigations have shown that there are significant blood flow changes during radiation or chemo-radiation therapy, suggesting that early blood flow may have prognostic value. Among those methods for oxygen and blood flow measurements, the near-infrared spectroscopy (NIRS) is more benefit with merit of non-invasive, portable, fast test, and inexpensive. Our instrument system combined near-infrared diffuse reflectance spectroscopy (DRS) and diffuse correlation spectroscopy (DCS) is capable of monitoring tissue oxygen and blood flow simultaneously. This hybrid diffuse optical instrument has already been used for monitoring of therapeutic effects (e.g., radiation therapy, chemotherapy) in tumors in human head \& neck and breast. In this study, we will use this hybrid instrument to investigate the hemodynamic responses to different therapies (radiation alone, radiation + chemotherapy) in patients with different nicotine levels. Baseline measurement of tissue oxygen saturation, total hemoglobin concentration and blood flow using a hybrid optical instrument (DRS for oxygen measurement and DCS for blood flow measurement). A hand-hold optical probe connected to the hybrid instrument will be placed on the head/neck tumor for about 3-5 minutes, then move it on the normal arm muscle for control purposeTumor oxygenation and flow measurements will be performed at the beginning of every week during the treatment period. During this monitoring process non-invasive blood pressure monitoring will also occur. Weekly optical measurements will be obtained during treatment.In this study we will investigate the hemodynamic responses to different nicotine levels and different therapies (radiation alone, radiation + chemotherapy).