DISEASE CHARACTERISTICS:

• Histologically confirmed renal cell carcinoma

  • Clinically confirmed metastatic disease (histologic documentation of metastatic disease not required)
• Sarcomatoid renal cell carcinomas allowed
• No pure sarcomas
• No collecting duct (duct of Bellini) tumors, oncocytomas, or transitional cell tumors

• Measurable disease

  • At least 20 mm by conventional techniques OR
  • At least 10 mm by spiral CT scan

  • Nonmeasurable lesions include the following:

    • Bone lesions
    • Leptomeningeal disease
    • Ascites
    • Pleural/pericardial effusion
    • Lymphangitis cutis/pulmonis
    • Abdominal masses that are not confirmed and followed by imaging techniques
    • Cystic lesions
• Patients with known brain metastases are eligible if they have undergone prior surgical resection and/or cranial irradiation, they currently do not require steroids or anticonvulsants, and there is no progressive disease on CT scan or MRI at least 4 weeks after completion of radiotherapy

PATIENT CHARACTERISTICS:

Age

• 18 and over

Performance status

• ECOG 0-2

Life expectancy

• Not specified

Hematopoietic

• Granulocyte count at least 1,500/mm^3
• Platelet count at least 100,000/mm^3

Hepatic

• Bilirubin no greater than 1.5 times upper limit of normal

Renal

• Creatinine clearance at least 30 mL/min

Cardiac

• No clinically significant cardiac disease
• No congestive heart failure
• No symptomatic coronary artery disease
• No cardiac arrhythmias not well controlled with medication
• No myocardial infarction within the past 12 months

Other

• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective barrier contraception during and for 3 months after study
• No prior severe reaction to fluoropyrimidine therapy or known sensitivity to fluorouracil
• No malabsorption syndrome or lack of physical integrity of the upper gastrointestinal tract that would preclude absorption of capecitabine

PRIOR CONCURRENT THERAPY:

Biologic therapy

• Not specified

Chemotherapy

• At least 4 weeks since prior chemotherapy and recovered
• No prior gemcitabine
• No prior fluoropyrimidines (e.g., fluorouracil, floxuridine, capecitabine, or fluorouracil-uracil)
• No other concurrent chemotherapy

Endocrine therapy

• See Disease Characteristics
• At least 4 weeks since prior megestrol
• No concurrent hormones (e.g., megestrol) except steroids for adrenal failure, hormones for nondisease-related conditions (e.g., insulin for diabetes), or intermittent dexamethasone as an antiemetic

Radiotherapy

• See Disease Characteristics
• At least 4 weeks since prior radiotherapy and recovered
• Prior radiotherapy to any lesion that may produce disability (e.g., unstable femur) allowed
• No concurrent palliative radiotherapy

Surgery

• See Disease Characteristics
• At least 4 weeks since prior major surgery and recovered

Other

• Any number of prior regimens allowed