Inclusion Criteria

DISEASE CHARACTERISTICS:

- Histologically confirmed carcinoma of the nasopharynx

- WHO type I, II, or III

- Recurrent locoregional or metastatic disease

- The following primary tumor sites or types are excluded:

- Nasal cavity

- Paranasal sinus

- Sinonasal neuroendocrine carcinoma

- Primary malignancy of the salivary gland

- Received at least 1, but no more than 2, prior chemotherapy regimens for recurrent
locoregional or metastatic disease

- Patients who are intolerant of OR have a condition that precludes platinum-based
chemotherapy are eligible

- Available tumor tissue

- Measurable disease

- At least 1 lesion that has not been irradiated within the past 6 months

- More than 10 mm by spiral CT scan (20 mm by conventional techniques)

- Pleural effusion or bone metastases are not considered measurable disease

- No CNS metastases unless stable for > 3 months

PATIENT CHARACTERISTICS:

Age

- 18 and over

Performance status

- ECOG 0-1

Life expectancy

- More than 3 months

Hematopoietic

- Neutrophil count ≥ 1,500/mm^3

- Platelet count ≥ 100,000/mm^3

Hepatic

- Bilirubin ≤ 1.5 times upper limit of normal (ULN)

- AST and ALT ≤ 2.5 times ULN (5 times ULN if due to liver metastases)

- Alkaline phosphatase ≤ 2.5 times ULN (5 times ULN if due to liver metastases; 10
times ULN if due to bone metastases)

Renal

- Creatinine clearance ≥ 30 mL/min OR

- Creatinine ≤ 1.5 times ULN

Cardiovascular

- No congestive heart failure

- No symptomatic coronary artery disease

- No cardiac arrhythmias not well controlled by medication

- No myocardial infarction within the past year

- No other clinically significant cardiac disease

Neurologic

- No history of uncontrolled seizures

- No clinically significant CNS disorder or psychiatric disability that would preclude
giving informed consent or complying with study treatment

Immunologic

- No prior unanticipated severe reaction to fluoropyrimidines

- No extreme sensitivity to fluorouracil

- No serious, uncontrolled infection

Other

- No other malignancy within the past 5 years except nonmelanoma skin cancer or
carcinoma in situ of the cervix

- No malabsorption syndrome of the upper gastrointestinal tract

- No other serious uncontrolled medical condition that would preclude study
participation

- Not pregnant or nursing

- Negative pregnancy test

- Fertile patients must use effective contraception

PRIOR CONCURRENT THERAPY:

Biologic therapy

- Not specified

Chemotherapy

- See Disease Characteristics

- More than 6 months since prior fluoropyrimidines, including fluorouracil

- More than 4 weeks since prior chemotherapy and recovered

Endocrine therapy

- Not specified

Radiotherapy

- See Disease Characteristics

- More than 4 weeks since prior radiotherapy

Surgery

- More than 4 weeks since prior major surgery and recovered

Other

- More than 4 weeks since prior investigational drugs