Inclusion Criteria

DISEASE CHARACTERISTICS:

- Histologically confirmed squamous cell carcinoma of the head and neck

- Primary site must be within the oral cavity, oropharynx, larynx, or hypopharynx

- Stage III or IV primary lesion at diagnosis

- No distant metastatic disease at diagnosis

- No multiple primary lesions

- Currently disease-free after treatment with 1 of the following:

- Complete tumor resection

- Radiotherapy or chemoradiotherapy alone*

- Resection followed by radiotherapy/chemoradiotherapy*

- No more than 4-16 weeks since prior surgery and/or radiotherapy/chemoradiotherapy
NOTE: *Radiotherapy must have been 70-72 Gy in 1.8-2.0 Gy fractions to the primary
tumor and clinically positive neck nodes and 44-50 Gy in 1.8-2.0 Gy fractions to
clinically negative nodes, including the lower neck

PATIENT CHARACTERISTICS:

Age

- 18 and over

Performance status

- ECOG 0-1

Life expectancy

- Not specified

Hematopoietic

- Absolute neutrophil count at least 1,500/mm^3

- Platelet count at least 100,000/mm^3

Hepatic

- Bilirubin no greater than 1.5 mg/dL

- AST and ALT no greater than 2 times upper limit of normal (ULN)

- Alkaline phosphatase no greater than 2 times ULN

Renal

- Creatinine no greater than 1.2 mg/dL

Other

- Not pregnant or nursing

- Negative pregnancy test

- Fertile patients must use effective contraception for 1 month prior to, during, and
for 1 month after study therapy

- Electrolytes normal

- Fasting serum triglyceride level no greater than 2 times ULN (anti-triglyceride
medication allowed)

- No other malignancy within the past 2 years except localized basal cell or squamous
cell skin cancer

- No other concurrent medical condition that would preclude study compliance

PRIOR CONCURRENT THERAPY:

Biologic therapy

- Not specified

Chemotherapy

- See Disease Characteristics

- At least 4 weeks since prior chemotherapy and recovered

- Prior neoadjuvant chemotherapy allowed

- Prior chemotherapy administered concurrently with radiotherapy allowed

- No other concurrent chemotherapy

Endocrine therapy

- Not specified

Radiotherapy

- See Disease Characteristics

- Recovered from prior radiotherapy

Surgery

- See Disease Characteristics

- Recovered from prior surgery

Other

- No history of megadose vitamin A (more than 25,000 I.U.)

- No other clinical trial enrollment that would preclude adjuvant systemic therapy

- No concurrent vitamin supplements containing vitamin A