Inclusion Criteria:

- Patients with histological proof (from the primary lesion and/or lymph nodes) of
squamous cell carcinoma of the oral cavity, oropharynx, or hypopharynx.

- Patients should have Stage III or IV disease, M0

- Patients must have life expectancy of at least 6 months and a Karnofsky performance
status of ≥ 70

- Age ≥ 18 years and ≤ 70 years

- No distant metastatic disease

- No clinically significant heart disease:

- No significant ventricular arrhythmia requiring medication with antiarrhythmics

- No symptomatic coronary artery disease (angina)

- No myocardial infarction within the last 6 months

- No second or third degree heart block or bundle branch block or clinically
significant conduction system abnormality

- Patients must sign a study-specific informed consent form

Exclusion Criteria:

- Histology other than squamous cell carcinoma

- Evidence of metastasis (below the clavicle or distant) by clinical or radiographic
means

- Prior complete resection of the primary tumor

- Prior chemotherapy (Bleomycin) for head and neck cancer or radiotherapy to the head
and neck

- Patients with simultaneous primaries

- Pregnancy

- Pulmonary pathologies (risk of decompression-induced pulmonary barotrauma):

- Current, untreated pneumothorax

- Previous history of pneumothorax

- Previous history of intrathoracic surgery

- History of pulmonary blebs or bullous lung disease

- Associated with CO2 retention

- Poorly controlled or associated with acute bronchospasm

- Where the hyperbaric physician deems the patient to have an unacceptable risk for
hyperbaric treatments

- Claustrophobia