Erlotinib and Radiation Therapy in Treating Older Patients With Stage I, Stage II, Stage III, or Stage IV Esophageal Cancer

DISEASE CHARACTERISTICS: * Biopsy-proven primary squamous cell carcinoma or adenocarcinoma of the esophagus or gastroesophageal (GE) junction * GE junction tumors with 50% or more tumor located in the esophagus determined by radiologic or endoscopic evaluation * Stage I-IVA disease determined by CT scan or MRI of the chest and abdomen * Stage IVB disease allowed if metastases to distant regional lymph nodes (celiac or cervical) only and no other sites * Not a surgical candidate and ineligible for chemotherapy due to any of the following: * Neuropathy * Cardiac disease * Performance status 2 * General overall condition felt by the investigator to be a contraindication to platinum-based therapy * Bronchoscopy with biopsy and cytology required if primary esophageal cancer is \< 26 cm from incisors * No evidence of clinically active interstitial lung disease (patients who are asymptomatic with chronic, stable, radiographic lung changes allowed) PATIENT CHARACTERISTICS: * ECOG performance status 0-2 * Life expectancy \> 4 months * WBC ≥ 3,000/mm³ * ANC ≥ 1,500/mm³ * Platelet count \> 100,000/mm³ * Bilirubin ≤ 1.3 mg/dL * ALT and AST ≤ 2.5 times upper limit of normal (ULN) * Alkaline phosphatase ≤ 2.5 times ULN * No prior malignancies except basal cell or squamous cell skin cancer, in situ cervical cancer, or superficial transitional cell bladder cancer, unless diagnosed and/or treated \> 2 years prior to current study and are without evidence of recurrence * No history of allergy to erlotinib or any of its excipients * No serious, uncontrolled, concurrent infection * No clinically serious, uncontrolled medical conditions that the investigator feels might compromise study participation * No lack of physical integrity of the upper gastrointestinal tract or malabsorption syndrome * No unwillingness to participate or inability to comply with the protocol for the duration of the study PRIOR CONCURRENT THERAPY: * No prior chemotherapy or radiotherapy for this tumor * No prior resection or attempted resection of esophageal cancer * No prior anti-epidermal growth factor receptor therapy (unless given in an adjuvant setting and completed at least 12 months earlier) * No participation in any investigational drug study within the past 4 weeks * No HIV-positive patients receiving antiretroviral therapy * No concurrent CYP3A4/5 inducers or inhibitors