Adjuvant Erlotinib After Completing Chemoradiotherapy in Locally Advanced Squamous Cell Carcinoma of the Head and Neck

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)