Gemcitabine Plus Cisplatin in Treating Patients With Metastatic Kidney Cancer

DISEASE CHARACTERISTICS: Histologically proven metastatic renal cell carcinoma No brain metastases PATIENT CHARACTERISTICS: Age: Over 18 Performance status: ECOG 0-2 Life expectancy: At least 12 weeks Hematopoietic: WBC at least 3,500/mm^3 Hematocrit at least 30% Platelet count at least 100,000/mm^3 Hepatic: Bilirubin no greater than 2.0 mg/dL AST and ALT no greater than 1.5 times upper limit of normal Renal: Creatinine no greater than 1.5 mg/dL OR Creatinine clearance at least 60 mL/min Cardiovascular: No uncontrolled hypertension No myocardial infarction within the past 8 weeks Other: Not pregnant or nursing Fertile patients must use effective contraception No other prior malignancy within the past 5 years except nonmelanomatous skin cancer, carcinoma in situ of cervix, prostate intraepithelial neoplasia, or superficial bladder cancer No significant psychiatric disease No active infection PRIOR CONCURRENT THERAPY: Biologic therapy: No more than 2 prior biologic response modifier regimens No concurrent biologic therapy Chemotherapy: No prior chemotherapy No other concurrent chemotherapy Endocrine therapy: Not specified Radiotherapy: Prior radiotherapy allowed if measurable disease is outside radiation port At least 28 days since prior radiotherapy No concurrent radiotherapy Surgery: Prior surgery allowed