Patients with node-positive disease (initially) undergo tumor and blood sample collection for biological studies. Samples are analyzed for ErbB-related activation via immunohistochemistry, in situ hybridization, and PCR/sequencing of genes/proteins, to detect DNA amplification and polysomy (for AKT, ErbB2, EGFR) and genomic losses (for PTEN) via FISH, and the ratio between EGFR and EGFRvIII via QRT-PCR. Patients with node-positive disease undergo at least elective neck dissection to evaluate the negative predictive value of PET scanning.