Selenomethionine in Reducing Mucositis in Patients With Locally Advanced Head and Neck Cancer Who Are Receiving Cisplatin and Radiation Therapy

Inclusion Criteria: * Biopsy-proven locally-advanced HNSCC, including those with cancers of the oral cavity, oropharynx, hypopharynx, larynx, nasopharynx or paranasal sinuses * Stage III, IVa or IVb disease * No prior definitive surgery for present diagnosis * Appropriate candidate for concurrent cisplatin and radiation as definitive treatment; patients who receive induction chemotherapy as part of a definitive treatment program that will include concurrent CRT are eligible for this study * Hemoglobin \>= 10 g/dL (100 g/l) * Absolute neutrophil count \>= 2,000 cells/mm\^3 (2 x 10\^9/l) * Platelets \>= 100,000 cells/mm\^3 (100 x 10\^9/l) * Serum creatinine =\< 1.5 mg/dL (133 umol/l) or calculated creatinine clearance \>= 50 ml/min using the Cockcroft-Gault formula * Eastern Cooperative Oncology Group (ECOG) performance status 0-2 * Able to give written informed consent * Be willing and able to comply with study procedures Exclusion Criteria: * Non-regional metastatic disease (stage IVc) * Previous malignancy within the last 5 years except for adequately treated basal or squamous cell carcinoma of the skin or cervical intra-epithelial neoplasia * Prior chemotherapy or radiotherapy for HNSCC, or any prior radiotherapy that would compromise delivery of a radical dose to the HNSCC * Known to be positive for hepatitis C or human immunodeficiency virus (HIV) * Unable to tolerate oral medication (unless a feeding tube is in place) * History of hypersensitivity to platinum drugs * Symptomatic peripheral neuropathy \>= National Cancer Institute (NCI)-Common Terminology Criteria for Adverse Events (CTCAE) grade II * Pregnant, lactating or unwilling to use adequate contraception * Women of child-bearing potential and men must agree to use adequate contraception (hormonal or barrier method of birth control; abstinence) prior to study entry and for the duration of study participation * Planned use of amifostine for prophylaxis against radiation-induced xerostomia * Patients taking selenium supplements in excess of 100 ug/day * Uncontrolled intercurrent illness including, but not limited to, ongoing or active infection, symptomatic congestive heart failure, unstable angina pectoris, clinically significant cardiac arrhythmia, or psychiatric illness/social situations that would limit compliance with study requirements * Evidence of any other significant medical disorder or laboratory finding that in the opinion of the Investigator compromises the subject's safety during the study