Inclusion Criteria

DISEASE CHARACTERISTICS:

- Histologically confirmed squamous cell carcinoma of the head and neck

- Stage III, IVA, or IVB

- Must have completed cisplatin- or carboplatin-based chemoradiotherapy within the past
4-12 weeks

- Prior radiotherapy must have been given with a radical intent with receipt of at
least 90% of planned dose

- No evidence of disease or presence of inoperable minimal residual disease, defined by
1 of the following:

- Complete response at primary tumor site and nodes (with or without nodal surgery
after chemoradiotherapy)

- Negative lymph node status (by physical or radiological exam) AND persistent
tumefaction less than 25% of original tumor size or residual mass due to
scarring

- Tumor tissue samples available for EGFRvIII mutation analysis

- No known brain metastasis

PATIENT CHARACTERISTICS:

Age

- 18 and over

Performance status

- ECOG 0-1

Life expectancy

- Not specified

Hematopoietic

- Absolute granulocyte count ≥ 1,500/mm^3

- Platelet count ≥ 100,000/mm^3

Hepatic

- ALT/AST < 2 times upper limit of normal (ULN)

- Bilirubin < ULN (unless due to Gilbert's syndrome)

Renal

- Creatinine < 1.5 times ULN

Cardiovascular

- No myocardial infarction within the past year

- No cardiac ventricular arrhythmias requiring medication

- No history of cardiac disease

- No uncontrolled high blood pressure

- No unstable angina

- No congestive heart failure

Ophthalmic

- No history of severe dry eye syndrome, Sjögren's syndrome, or keratoconjunctivitis
sicca

- No severe exposure keratopathy

- No abnormal slit-lamp examination using a vital dye (e.g., fluorescein or
Bengal-Rose)

- No abnormal corneal sensitivity test (Schirmer test or similar tear production test)

- No disorder that might increase the risk for epithelium-related complication (e.g.,
bullous keratopathy, aniridia, severe chemical burns, or neutrophilic keratitis)

- No congenital abnormality (e.g., Fuch's dystrophy)

- No ocular inflammation or infection

Gastrointestinal

- Able to take oral medication

- No gastrointestinal (GI) tract disease requiring IV alimentation

- No uncontrolled inflammatory GI disease (e.g., Crohn's disease or ulcerative colitis)

- No active peptic ulcer disease

Other

- Not pregnant or nursing

- Negative pregnancy test

- Fertile patients must use effective contraception

- No serious active infection

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

- No prior allergic reaction to compounds of similar chemical or biological composition
to erlotinib

- No other malignancy with the past 5 years except adequately treated non-melanoma skin
cancer (unless in the same area treated with radical radiotherapy) or carcinoma in
situ of the cervix

PRIOR CONCURRENT THERAPY:

Biologic therapy

- Not specified

Chemotherapy

- See Disease Characteristics

- Recovered from prior chemotherapy

Endocrine therapy

- Not specified

Radiotherapy

- See Disease Characteristics

- Recovered from prior radiotherapy

Surgery

- See Disease Characteristics

- No prior surgical procedure affecting absorption

- No concurrent ophthalmic surgery

Other

- More than 4 weeks since other prior investigational drugs

- No other concurrent investigational agents

- No other concurrent anticancer therapy

- Concurrent oral anticoagulants (e.g., warfarin) allowed provided there is increased
vigilance with respect to INR

- Concurrent nasogastric or gastrostomy tube feeding for dysphagia allowed provided
there is no evidence of significant residual mucositis (i.e., > grade 1)