Cytochlor and Tetrahydrouridine as Radiosensitizers and Cisplatin Combined With Radiation Therapy in Treating Patients With Advanced Squamous Cell Carcinoma of the Oral Cavity (Mouth) or Oropharynx (Throat)

OBJECTIVES: Primary * Determine the dose range of cytochlor to be used in phase II trials, based on safety, toxicity, and tissue selectivity, in patients with advanced squamous cell carcinoma of the oral cavity or oropharynx. * Determine the safety and toxicity profile of cytochlor, tetrahydrouridine, and concurrent radiotherapy followed by radiotherapy alone in these patients. * Determine the percentage of cancer cells vs normal cells that incorporate cytochlor in the DNA of patients treated with this regimen. * Determine the percentage replacement of thymine by 5-chlorouracil in tumors vs normal tissue of patients treated with this regimen. Secondary * Determine the tissue selectivity of this regimen in these patients. * Determine the level of cytochlor and its metabolites within the serum and urine of these patients during combination treatment and before radiotherapy alone is initiated. * Determine the pharmacokinetics of this regimen in these patients. OUTLINE: This is an open-label, dose-escalation study of cytochlor. Patients receive tetrahydrouridine IV over 5 minutes followed by cytochlor IV for 3 days on week 1 and 5 days a week on weeks 2-4 and cisplatin IV over 30-60 minutes once in weeks 2 and 5. Patients also undergo radiotherapy 5 days a week during weeks 2-7. Treatment continues in the absence of disease progression or unacceptable toxicity. Cohorts of 3-6 patients receive escalating doses of cytochlor until the maximum tolerated dose (MTD) is determined. The MTD is defined as the dose at which 1 of 3 or 3 of 6 patients experience dose-limiting toxicity. Patients are followed at 1 month, monthly for 3 months, every 3 months for up to 1 year, every 4 months for 1 year, every 6 months for 1 year, and then annually thereafter. PROJECTED ACCRUAL: A total of 3-18 patients will be accrued for this study within 2 years.