OBJECTIVES: I. Compare the complete response rate following radiotherapy with or without tirapazamine (SR-4233) in patients with N1 squamous cell carcinoma of the head and neck. II. Compare the complete response rate to induction chemotherapy with cisplatin (CDDP) and fluorouracil (5-FU) with and without SR-4233 followed by concurrent CDDP/5-FU plus radiotherapy with and without SR-4233 in patients with N2 or N3 squamous cell carcinoma of the head and neck. III. Assess whether tumor hypoxia contributes to tumor resistance to treatment by measuring oxygen tension in cervical lymph node metastases and correlating these results with treatment response in both groups of patients.

OUTLINE: This is a randomized study. Patients are stratified according to pO2 values (high vs low). Patients are randomized to one of two treatment arms. Arm I: Patients receive induction chemotherapy consisting of fluorouracil IV continuously on days 1-5 and cisplatin IV over 4 hours on day 1. Treatment is repeated every 21 days for 2 courses. Patients who achieve at least partial response proceed to chemoradiotherapy consisting of cisplatin IV over 30-60 minutes, three times a week, during weeks 1 and 5. Patients also receive fluorouracil IV continuously for 4 days beginning on day 43 and again on day 71. Radiotherapy begins on day 43 (week 1) for 5.5 weeks. Patients with no response or progressive disease after induction chemotherapy proceed to salvage surgery. Arm II: Patients receive induction chemotherapy as in arm I plus tirapazamine IV over 1.0-2.5 hours prior to cisplatin. Patients proceed as in arm I. Those patients receiving chemoradiotherapy also receive tirapazamine IV on the same days as cisplatin. Some patients receive further radiotherapy and/or surgery. Patients are followed monthly for 1 year, every 2 months for 1 year, every 3 months for 1 year, every 6 months for 2 years, then annually thereafter.

PROJECTED ACCRUAL: A total of 60 patients will be accrued for this study over approximately 5 years.

DISEASE CHARACTERISTICS: Biopsy proven squamous cell carcinoma of the following head and neck sites: Hypopharynx Oral cavity Larynx Oropharynx Nasal cavity Unknown primary Paranasal sinus Histologically proven poorly differentiated carcinoma of the following head and neck sites: Hypopharynx Oral cavity Larynx Oropharynx Nasal cavity Paranasal sinus Stage III/IV (T0-4 N1-3 M0-2) disease

PATIENT CHARACTERISTICS: Age: Over 17 Performance status: ECOG 0-2 Hematopoietic: WBC at least 3,000/mm3 Hepatic: Bilirubin no greater than 2.0 mg/dL AST no greater than 100 U/L Renal: Creatinine no greater than 2.0 mg/dL Creatinine clearance at least 60 mL/min (patients in Group N2-N3) Other: No second malignancy within 5 years except curatively treated nonmelanomatous skin carcinoma Not pregnant or nursing Negative pregnancy test required Effective contraception required of fertile women

PRIOR CONCURRENT THERAPY: Biologic therapy: No prior biologic therapy Chemotherapy: No prior chemotherapy Endocrine therapy: Not specified Radiotherapy: Prior radiotherapy to primary tumor allowed No prior radiotherapy to site of metastatic neck disease Surgery: Prior surgery allowed