Cisplatin, Bevacizumab, and Intensity-Modulated Radiation Therapy in Treating Patients With Stage III or Stage IV Head and Neck Cancer

Inclusion Criteria: * Stage III/IV HNSCC without distant metastasis, previously untreated. Patients with stage II squamous cell carcinoma of the hypopharynx will also be eligible. * Adequate renal function, with serum creatinine ≤ 1.5 mg/dL. Patients with serum creatinine \> 1.5 mg/dL may be eligible if calculated creatinine clearance ≥ 55 ml/min by Cockcroft and Gault equation (or 24-hour urine collection). * Age ≥ 18 years * Karnofsky performance status ≥70% * Adequate bone marrow function: absolute neutrophil count ≥ 1,500/μl, platelets ≥ 100,000/μl, hemoglobin ≥ 9 gm/dl * Adequate hepatic function: Total bilirubin ≤ 1.5 X UNL (patients with Gilbert's syndrome as the cause of hyperbilirubinemia may be eligible if total bilirubin ≤ 2.5 X UNL), aspartate aminotransferase (AST) ≤ 2.5 X UNL, alanine aminotransferase (ALT) ≤ 2.5 X UNL, alkaline phosphatase ≤ 2.5 X UNL. * Men and women of childbearing potential must be willing to consent to using effective contraception while on treatment and for at least 3 months thereafter. * Patients must have ability to understand and the willingness to sign a written informed consent document. Exclusion Criteria: * Prior chemotherapy or radiation therapy for HNSCC * Prior treatment with bevacizumab or other agents specifically targeting VEGF * Other active malignancy, other than indolent malignancies which the investigator determines are unlikely to interfere with treatment or efficacy analysis. For example, patients with non-melanoma skin cancer, in situ carcinoma of the cervix, or prostate cancer within the no current biochemical (PSA) or radiologic evidence of disease may enroll. * Patients with nasopharyngeal carcinoma * Patients who will receive amifostine as part of the radiation treatment plan * Patients with skin breakdown/ulceration (CTCAE version 3.0, grade 2 or higher). * Patients with hearing loss requiring hearing aid or intervention (i.e. interfering in a clinical significant way with activities of daily living). * Patients with multifocal peripheral sensory alterations or paresthesias (including tingling) interfering with function, per patient report (example: activities of daily living). * History of arterial thromboembolic events, including transient ischemic attack (TIA), cerebrovascular accident (CVA), unstable angina, or myocardial infarction (MI) within the last 3 years. * Urine protein: creatinine (UPC) ratio ≥ 1.0 at screening. A random urine sample is collected. Total protein (mg/dL) and spot creatinine (mg/dL) are ordered for this sample. The UPC ratio is calculated from the results of these tests. * International normalized ratio (INR) \> 1.5 or activated partial thromboplastin time (aPTT) \> 1.5 X upper limits of normal (UNL), * Current use of warfarin, current use of heparin or low-molecular weight heparin, chronic daily treatment with aspirin (\> 325 mg/day) or nonsteroidal antiinflammatory medications known to inhibit platelet function. Treatment with dipyramidole (Persantine), ticlopidine (Ticlid), clopidogrel (Plavix) and or cilostazol (Pletal) is not allowed. * Patients with gross hemoptysis or hematemesis (defined as bright red blood of 1 teaspoon of more) within 1 month prior to Day 1 protocol treatment will be excluded from this trial. Patients with incidental blood mixed with phlegm are not excluded. * Esophageal varices, non-healing ulcer, wound, or bone fracture are exclusion criteria. However, patients with skin breakdown overlying malignant neck lymphadenopathy may be eligible, at the discretion of the investigator. * Anatomic lesion that increases the risk of serious hemorrhage, such as encasement or invasion of major blood vessels by primary tumor and/or by involved lymph nodes * Blood pressure of \> 150/100 mmHg * New York Heart Association (NYHA) Grade II or greater congestive heart failure. * Clinically significant peripheral vascular disease * History of bleeding diathesis or hemorrhagic disorder, or coagulopathy. * Major surgical procedure or significant traumatic injury within 28 days prior to treatment with bevacizumab * Core biopsy within 15 days prior to treatment with bevacizumab. * Minor surgical procedures such as fine needle aspirations or placement of percutaneous gastrostomy tube (PEG) less than 7 days prior to treatment with bevacizumab * History of abdominal fistula, gastrointestinal perforation, or intra-abdominal abscess within 6 months prior enrollment. * Inability to comply with study and/or follow-up procedures * Women who are pregnant or lactating