Gefitinib and PEG-Interferon Alfa-2b in Treating Patients With Unresectable or Metastatic Kidney Cancer

DISEASE CHARACTERISTICS: * Histologically or cytologically confirmed renal cell carcinoma * Metastatic or advanced/unresectable disease * Measurable or nonmeasurable disease as defined by RECIST criteria * No uncontrolled brain metastases * Patients with adequately treated brain metastases who are not taking anticonvulsants and corticosteroids may be eligible PATIENT CHARACTERISTICS: * Karnofsky performance status 60-100% * Life expectancy ≥ 12 weeks * WBC ≥ 3,500/mm³ * Platelet count ≥ 100,000/mm³ * Absolute granulocyte count ≥ 1,500/mm³ * Creatinine ≤ 2.0 mg/dL OR creatinine clearance ≥ 50 mL/min * Bilirubin ≤ 1.5 mg/dL * AST ≤ 2 times upper limit of normal (ULN) * Not pregnant or nursing * Negative pregnancy test * Fertile patients must use effective contraception * No other malignancy within the past 5 years except adequately treated basal cell or squamous cell carcinoma of the skin, carcinoma in situ of the cervix, or adequately treated stage I or II cancer from which the patient is currently in complete remission * No known severe hypersensitivity to gefitinib or its excipients * No incomplete healing from previous oncologic or other major surgery * No unresolved chronic toxicity \> grade 2 from previous anticancer therapy (except alopecia and anemia) * No evidence of clinically active interstitial lung disease * Patients with chronic stable radiographic changes who are asymptomatic are eligible * No evidence of severe or uncontrolled systemic disease (e.g., unstable or uncompensated respiratory, cardiac, hepatic, or renal disease) * No other significant clinical disorder or laboratory finding that would preclude study participation PRIOR CONCURRENT THERAPY: * More than 30 days since prior nonapproved or investigational drugs * More than 6 weeks since prior aldesleukin or interferon and recovered * At least 3 weeks since prior radiotherapy * No prior gefitinib * Prior chemotherapy or biological therapy allowed * Prior or concurrent bisphosphonate therapy for bone metastases allowed * No concurrent phenytoin, carbamazepine, rifampin, barbiturates, phenobarbital, or Hypericum perforatum (St. John's wort) * No other concurrent agents specifically designed to inhibit the epidermal growth factor receptor (EGFR) * No concurrent radiotherapy to measurable lesions